PUBLIC HEALTH BULLETIN 
No. 256 
PLUMBING 
AND PUBLIC HEALTH 
FEDERAL SECURITY AGENCY 
U. S. PUBLIC HEALTH SERVICE 
WASHINGTON, D. C. U. S. PUBLIC HEALTH SERVICE 
FEDERAL SECURITY AGENCY 
Public Health Bulletin No. 256 
PLUMBING AND PUBLIC HEALTH 
By 
ARTHUR B. CRONKRIGHT, Project Supervisor 
and 
ARTHUR P. MILLER, Sanitary Engineer 
U. S. Public Health Service 
From the Division of Domestic Quarantine 
(States’ Relations) 
PREPARED BY DIRECTION OF THE SURGEON GENERAL 
UNITED STATES 
GOVERNMENT PRINTING OFFICE 
WASHINGTON: 1940 
For sale by the Superintendent of Documents, Washington, D. C. - -- -- -- Price 30 cents ORGANIZATION 
of the 
National Institute Of Health 
Thomas Parran, Surgeon General, United States Public Health 
Service 
L. R. Thompson, Director, National Institute of Health 
Division of Biologics Control.—Chief, Senior Surgeon W. T. 
Harrison. 
Division of Chemistry.—Chief, Prof. C. S. Hudson, 
Division or Infectious Diseases.—Chief, Senior Surgeon R. E. Dyer. 
Division of Industrial Hygiene.—Acting Chief, P. A. Surgeon 
P. A. Neal. 
Division of Pathology.—Chief, Surgeon R. D. Lillie. 
Division of Pharmacology.—Acting Chief, Chief Pharamcologist 
M. I. Smith. 
Division of Public Health Methods.—Chief, G. St. J. Perrott. 
Division of Zoology.—Chief, Prof. W. H. Wright. 
National Cancer Institute.—Chief, Pharmacologist Director Carl 
VoEGTLIN. 
(HI; CONTENTS 
Page 
Introduction 1 
Chapter I. Water-borne diseases 3 
Water-borne diseases 3 
Definition of terms 6 
Description of plumbing hazards 7 
Chapter II. Digest of correlated activities 18 
American Society of Sanitary Engineering 18 
Pasadena (Calif.) Water Department 19 
Fresno (Calif.) Public Works Department 19 
National Association of Master Plumbers 19 
Wisconsin State Board of Health 21 
National Bureau of Standards 22 
St. Louis (Mo.) Health Department 22 
Baltimore (Md.) Health Department 23 
San Francisco (Calif.) Water Department 24 
Connecticut State Department of Health 25 
New Hampshire State Board of Health 27 
New Bedford (Mass.) Water Department 27 
Maine Department of Health and Welfare 28 
Kahler Corporation, Rochester, Minn 28 
American Water Works Association 29 
Department of Buildings and Safety Engineering, Detroit 30 
Copper and Brass Research Association 31 
Massachusetts Department of Public Health 31 
American Public Health Association 31 
Twentieth Annual Texas Water Works and Sewerage Short School 31 
Louisiana State Department of Health 32 
Minnesota State Department of Health 32 
El Paso, Tex 33 
Houston, Tex 33 
Chapter III. Survey of plumbing in Federal buildings in New York and 
Detroit 35 
Surveys 35 
Organization of staff 36 
Scope of work 37 
Report preparation 40 
Summary of results 41 
Discussion of certain phases of surveys 46 
Works Progress Administration beneficiaries 46 
Development of procedure 46 
Drawings, sketches and photographs 47 
Detailed descriptions 49 
Record of fixtures 52 
Recording progress of survey 52 
Suggested organization for future surveys 55 
Personnel 55 
Measurement of progress and efficiency 56 
(V) VI 
Page 
Chapter IV. Special investigations in connection with the plumbing survey 
of Federal buildings 57 
Quality of water in overhead tanks 58 
Filter study 60 
Vacuum frequency study 61 
Chapter V. Suggested method of comparing results of plumbing inspec- 
tions 73 
Tentative plumbing inspection rating system 73 
Building hazard rating 73 
Fixture hazard rating 74 
Distribution system hazard rating 75 
Pressure hazard rating 75 
Application of system 76 
Chapter VI. Corrective measures 81 
Conclusions 84 
Bibliography 86 
Appendix A 106 
Appendix B 113 
LIST OF TABLES 
CHAPTER X 
I. Water-borne diseases 4 
11. Outbreaks of illness attributed to the presence of interconnections. . 5 
CHAPTER XI 
111. Percent of fixtures surveyed and found unsatisfactory in regard to 
water inlet and drainage outlet 
CHAPTER 111 34 
IV. Number of structures and floor area 39 
V. Structures classified by height I 39 
VI. Classification of structures by use_ _ , 40 
VII. Number of fixtures inspected 42 
VIII. Number of disapproved fixtures 44 
IX. Average number of fixtures inspected per working-party-month in 
New York 54 
X. Number of fixtures per thousand square feet for various classifica- 
tions of buildings, New York and Detroit 56 
CHAPTER xv 
XI. Results of bacteriological tests of water samples from twenty over- 
head, open-top tanks in a municipal comfort station 60 
XII. Essential characteristics of buildings included in vacuum study 63 
XIII. Lowest pressures recorded in consecutive fifteen-minute intervals... 64 
XIV. Results of study of vacuum frequencies of six New York office 
buildings 72 VII 
CHAPTER V 
XV. Ratings of five New York office buildings 78 
XVI. Ratings of five New York office buildings by age of building 78 
Page 
LIST OF FIGURES 
CHAPTER I 
1 Flush valves 8 
2 Flush tanks 9 
3 Other plumbing fixtures 11 
4 Dishwasher and laundry washing machine 13 
5 Bedpan washer and sterilizer 14 
6 Hospital sterilizing equipment 14 
7 Organization chart 37 
8 Location of groups of buildings inspected in New York 38 
9 Location of groups of buildings inspected in Detroit 38 
10 Isometric view of subbasement plumbing 46 
11 Sewage ejector interconnection 48 
12 Suction sump pump 50 
13 Priming line for centrifugal pump 50 
14 Plumbing survey file card 52 
15 Progress chart by Federal departments 53 
16 Survey organization for plumbing inspection 54 
chapter m 
17 New York City comfort station; location of overhead, open-top tanks. 59 
18 Typical pressure gage installation 62 
19 Building A 66 
20 Building B 67 
21 Building C 68 
22 Building D 69 
23 Building E 70 
24 Building F 71 
25 Building B typical pressure chart 72 
CHAPTER IV 
CHAPTER VI 
26 Lavoratory with drain out of window 82 
27 Hot water tank drain line 82 
28 Direct drain and overflow connection 82 
29 Potato peeler interconnection 82 
30 Submerged hose in sink 82 
31 Water-soil line interconnection 83 PLUMBING AND PUBLIC HEALTH 
INTRODUCTION 
That phase of plumbing having to do with the supplying and using 
of water has in the past few years assumed an increasing importance 
in its relation to public health. For the past few decades the ratio of 
urban to rural population has been steadily increasing and with this in- 
flux of people to the cities has come a corresponding increase in the 
complexities met with in supplying a safe and pure drinking water. 
The introduction of the sand filter and of chlorine as a disinfecting and 
sterilizing agent has resulted in a definite and commendable decrease 
in the number of cases of water-borne diseases. It was not until re- 
cently, however, that the development of spontaneous and sporadic 
outbreaks of these diseases awakened health and waterworks officials 
to a realization that something besides the protection of the source of 
water supply and the delivery of pure water to conduits was necessary 
in order to protect the health of the public. Various decisions of the 
courts have held the water company or the municipality responsible for 
the delivery of safe water to the consumers. These decisions aided in 
focusing attention on the possibility of contaminating the water 
through cross-connections with secondary supplies of water. The 
demonstrating of such a possibility and the tracing of the cause of 
several outbreaks of disease to such connections resulted in a concerted 
effort on the part of health and water-works officials to eliminate 
and control these hazards. 
The step from the realization of the dangers of cross-connections to 
the belief that the existence of faulty and defective plumbing in a 
building might cause, under similar conditions, a disastrous effect on 
the quality of the water supply or on the health of the public was a 
natural but slow one. A few scattered outbreaks of water-borne dis- 
eases were shown to be the result of the existence of such conditions, 
and this resulted in arousing the interest of several individuals and 
organizations to the danger of such installations. It was not, however, 
until the outbreak of amebic dysentery in two hotels in Chicago in 
1933 1 that health and water-works officials and the plumbing industry 
Submitted for publication July 1, 1938. 
1 “Water-borne Outbreaks in the United States and Canada 1930-36 and their Sig- 
nificance.” American Public Health Association Yearbook, p. 137. 2 
in general realized the inherent hazards of defective and poorly de- 
signed plumbing fixtures and installations. That epidemic, resulting 
in 1,409 cases and 98 deaths, was attributed to the existence of old and 
faulty piping and to a poorly designed plumbing system. The wide- 
spread publicity attending this outbreak enabled the facts of the epi- 
demic to be brought before a large number of persons affiliated with 
this subject and caused a renewal of interest which has been productive 
of much good since then. 
This study was designed to have three major objectives. The first 
was to bring together under one cover all the information on this sub- 
ject which it was possible to secure. This should be helpful to the 
many persons who are now intensely interested in this public health 
problem. The second was to amplify the summary of the project which 
involved the inspection of plumbing in New York City and Detroit 
Federal buildings {260) in such a way that the technique used would 
be available to others and that improvements in the methods employed 
could be pointed out. The third objective was to focus attention on 
this subject and to emphasize the importance of approaching it with 
an open mind and in a conservative, well-balanced, and rational way. 
That interconnections in plumbing may present a hazard to public 
health cannot be denied, but the determination of the degree of hazard 
in the buildings in any locality is of the utmost importance before pub- 
lic officials divert time and money to corrective measures. 
The authors wish, at this time, to gratefully acknowledge the assis- 
tance given by all public officials, company officers and individuals who 
so kindly responded to our requests for data. Without their coopera- 
tion, this study could not have been made so complete. CHAPTER I 
WATER-BORNE DISEASES. DEFINITION OF TERMS. DESCRIPTION 
OF PLUMBING HAZARDS 
Water-Borne Diseases 
Water has for many years been established as a medium for the 
spread and transmission of disease organisms. Among the first and 
most noted outbreaks of disease, the spread and transmission of which 
were associated with water, are: the outbreak of Asiatic cholera in 
London in 1854;2 the epidemic of typhoid fever in Plymouth (Penn- 
sylvania) in 1885;3 and the outbreak of Asiatic cholera in Hamburg, 
Germany, in 1892.4 
There are a number of diseases which may be spread through the 
medium of water either by contaminating the drinking-water supply 
or through the overcrowding and inadequate control of swimming 
pools or bathing places. The latter means of spreading infections 
and disease-producing organisms has received considerable attention 
of late and numerous regulations controlling the operation and use 
of swimming pools and bathing places have been promulgated and 
enforced. Previous to the enforcement of these regulations and the 
development of an adequate control of the water in these pools, it 
was possible to spread eye-and-ear, respiratory, and intestinal dis- 
eases by this means. 
The prevalance of epidemics of disease spread through the con- 
tamination of the domestic water supply has been reported by Wol- 
man and Gorman in their study of water-borne typhoid fever out- 
breaks of 1920-305 and in a subsequent report covering the years 
1930-36.° These reports discuss and classify all outbreaks of water- 
borne diseases affecting more than five persons as to cause, method 
of spread, and severity. In the first report, no classification 
2 “On the Mode of Communication of Cholera.” Report on Cholera Outbreak in the 
Parish of St. James, Westminster, During the Autumn of 1854. Presented to the Vestry 
by the Cholera Inquiry Committee. J. Churchill, London, 1855, 162 pp. 
3 “First Annual Report, State Board of Plealth and Vital Statistics of Pennsylvania.” 
Harrisburg, Pa., 1886, p. 176—195. 
4 Rosenau, M. J. “Preventive Medicine and Hygiene.” sth Edition. D. Appleton and 
Co., New York and London, p. 1058 (1927). 
5 Wolman, A., and Gorman, A. E. “The Significance of Water-borne Typhoid Fever 
Outbreaks, 1920-30.” Williams and Wilkins Co., Baltimore, Md. (1931). 
8 Water-borne Outbreaks in the United States and Canada, 1930-36, and Their Sig- 
nificance.” American Public Health Association Yearbook, 1937—38, p. 137. 4 
was made for the minor gastrointestinal disturbances that appear 
to be of epidemic character. Outbreaks of this nature were 
classified under the heading of dysentery. In the later report, 
however, the dysenteries are separated from the minor intestinal dis- 
turbances and the latter are grouped under the heading of diarrhea. 
Table I lists a number of diseases which may be spread through 
contamination of the domestic water supply together with their 
etiological agent, mode of transmission, and prevalence. Water- 
borne jaundice has been omitted from this list pending further in- 
formation as to the causative agent and the prevalence of the disease. 
Of the various diseases listed in table I the most important from a 
health standpoint, at least in this country, are typhoid and para- 
typhoid fevers, the dysenteries, hookworm, and diarrhea. The in- 
cidence of the other diseases listed is very small. 
Disease 
Etiological agent 
Mode of transmission 
Prevalence 
Ancylostomiasis 
Necator amcrieanus and 
Contaminated soil, water con- 
Endemic in Southern 
(hookworm dis- 
rarely Ancylostoma 
taining larvae, soiled food, 
States particularly 
ease). 
duodenale. 
hand to mouth transmission 
from handling soiled objects. 
among white children 
of school age. 
Cholera 
Cholera vibrio, Vibrio 
comma. 
By water and food polluted by 
infectious agent; direct con- 
tact, carriers, flies, and contact 
with articles freshly soiled by 
discharges of infected persons 
or carriers. 
Rare in North America. 
Dysentery, Ame- 
bic (Amebiasis). 
Endamoeba histolytica.. 
By drinking contaminated 
water, by eating infected food, 
hand to mouth transfer of in- 
fected material. 
Not common in North 
America, epidemic out- 
breaks rare. 
Dysentery, Bacil- 
Dysentery bacillus, 
Shigella dysenteriae, 
Shigella para-dysen- 
teriae. 
Eating infected food, hand to 
Endemic, epidemic and 
lary. 
mouth transfer of infected 
material: flies, objects soiled 
with discharges of infected 
persons or carriers, drinking 
polluted water. 
sporadic. Most com- 
mon in summer months 
and in subtropical and 
tropical areas. 
Typhoid fever 
Typhoid bacillus, Eber- 
thella typhi. 
Conveyance of the specific 
micro-organism by direct or 
indirect contact with a source 
of infection. Among indirect 
means of transmission are con- 
taminated water, milk, and 
shellfish and probably flies. 
Occurs sporadically and 
as small contact and 
carrier epidemics, en- 
demic in small south- 
ern rural areas. 
Paratyphoid fever. 
Paratyphoid bacillus A, 
B, or C; Salmonella 
paratyphi: Salmonella 
schottmiielleri. 
Directly by personal contact, 
indirectly by contact with ar- 
ticles freshly soiled by the dis- 
charges of infected persons or 
through milk, water, or food 
contaminated by such dis- 
charges, probably by flies. 
Relatively rare, occurs 
sporadically or in small 
local carrier or contact 
epidemics. 
Schistosomiasis 
Animal parasites of the 
Ova hatch in water and enter 
Not indigenous in the 
(flukes). 
class Trematoda, ge- 
nus Schistosoma; S. 
japonicum, S. hema- 
tobium, S. manson. 
mollusk, genus Planorbis in 
the West Indies, in the mol- 
lusk they multiply and de- 
velop into larval forms called 
“eercariae”, which on leaving 
the mollusk penetrate the skin 
of man and certain animals. 
United States at pres- 
ent. 
Diarrhea 
A number of specific 
organisms suspected, 
among which are the 
coli-aerogenes group 
bacteria. 
Polluted water and other causes 
not known. 
Universal, epidemic, en- 
demic, and sporadic. 
1 American Public Health Association. Report of the Subcommittee on Communicable Diseases Con- 
trol, of the Committee on Research and Standards. “The Control of Communicable Diseases.” Public 
Health Reports, 50:1017 (Aug. 9, 1935). 
Table I.I—Water-borne diseases 5 
By referring to the two reports on the significance of water-borne 
disease outbreaks already mentioned, it can be seen that the cause of 
over 50 percent of the outbreaks was the use of untreated surface or 
ground water that had in some manner become infected. It is inter- 
esting to note, however, that slightly over 10 percent of the outbreaks 
occurring from 1920 to 1937 in this country were due to contamina- 
tion of the water in the distribution system and that in the majority 
of these cases contamination had reached the systems through the 
existence of cross-connections with auxiliary sources of water. No 
classification was made in the reports to indicate the type of cross- 
connections responsible for the various outbreaks. 
In an effort to determine the number of outbreaks of water-borne 
diseases that could be attributed to the existence of defective and 
poorly designed plumbing in buildings, a questionnaire was sent to 
130 State and municipal health officers. Excepting the Chicago 
epidemic of amebic dysentery, only 3 outbreaks of illness, including 
1 of lead poisoning, were reported as having any relation to the 
existence of faulty plumbing in buildings. These are tabulated in 
table 11. 
Table ll.—Outbreaks of illness attributed to the presence of interconnections 
Location 
Type of 
building 
Number 
of cases 
of illness 
Type of illness 
Cause of outbreak or general remarks 
Marion County, Ind— 
Convent-. 
30 
Typhoid fever 
Interconnection between frostproof 
water closet and well water distribut- 
ing system permitted backflow of 
sewage into system. 
St. Paul Minn 
Laundry.. 
Several 
Typhoid fever 
Drinking fountain installed in such a 
manner that the drainage from it 
returned to the water supply tank. 
Original infection presumed to have 
been introduced by means of soiled 
laundry. 
Baltimore, Md 1 
Industrial 
plant. 
2 
Lead poisoning 
Direct connection between the domes- 
tic water supply and a pump used to 
pump a highly poisonous lead com- 
pound. The connection was made 
for the purpose of priming the pump. 
i See Bibliography, No. 66. 
The lack of more authenticated cases of disease outbreaks from 
this cause should not result in minimizing the dangers inherent in 
such connections and installations. It is extremely difficult in many 
cases to find and designate a particular plumbing hazard as the cause 
of an outbreak. The combination of circumstances under which a 
water supply may become contaminated may not be apparent. The 
extended incubation periods of the various diseases may result in 
the development of the outbreak after the condition producing the 
contamination of the water has been removed or corrected. Also, 
in the case of small outbreaks of disease, adequate investigation 
may not be resorted to for determining their causes. A thorough 6 
investigation into the cause of each case of disease that may be 
water-borne, especially typhoid fever and the dysenteries, might 
result in the correlation of many of these scattered outbreaks with 
the existence of faulty and defective plumbing. Until a more wide- 
spread interest is aroused in this subject and a more thorough study 
is made of all cases of water-borne diseases, whether of epidemic 
proportions or not, the extent to which plumbing defects are respon- 
sible for the spread and transmission of infections will not be 
definitely known. 
Definition of Terms 
Before discussing and explaining the various types of plumbing 
defects by which the water supply may become contaminated, it is 
necessary to define the various terms to be used throughout this dis- 
cussion. The several investigators in this field each use a terminol- 
ogy peculiar to themselves and this impedes a profitable comparison 
of their work. 
Cross-connections.—The definition of the term “cross-connection,” 
except in quoted material, coincides with the definition given in a 
report of the committee on cross-connections of the New England 
Water Works Association,7 which is: “* * * a connection between 
the distribution system of a public or private, potable water supply 
and a private or secondary, nonpotable supply.” 
The terms “private or secondary, nonpotable supply” shall be taken 
to indicate a supply of water, for either industrial, fire, auxiliary, 
or other purposes and shall in no sense be taken to mean waste 
material, sewerage systems, or the like. 
Interconnection.—Whereas a cross-connection represents an instal- 
lation between two water supplies, there are often many connections 
to the water distribution system, outside and inside of buildings, 
involving no private or secondary, nonpotable supply, through which 
the potable supply may become contaminated. 
Therefore, any connection to the distribution system of a public or 
private potable water supply, other than one with a private or sec- 
ondary nonpotable supply through which contamination may enter 
the potable water-supply lines, shall be known as an interconnection. 
Back-siphonage.—The phenomenon characterized by a reversal of 
flow in a plumbing system, fixture or appliance and caused by the 
development of a less-than-atmospheric pressure in the supply line to 
the installation is back-siphonage. 
Vacuum.—An absolute pressure of less than 1 atmosphere (14.7 
Ib/sq. in. at sea level) shall be termed a vacuum. (Exception to this 
definition is made in chapter IV for specific reasons given there.) 
1 Report of the Committee on Cross-connections. Journal of the New England Water 
Works Association, 43 : 1; 79 (March 1929). 7 
Submerged inlet.—Any unrestricted water-supply connection or 
inlet to a plumbing fixture, appliance, or installation, other than a 
direct enclosed connection, which is located a distance of less than 
21) or 2 above the highest possible water level of the fixture, 
appliance, or installation, where D is the diameter of the inlet, if cir- 
cular, and A is the area of the inlet, if other than circular, shall be 
known as a submerged inlet. {139) 
Highest possible irater level.—The highest point to which water 
may rise in a fixture should the drain from the fixture become clogged 
shall be known as the highest possible water level of that fixture. 
Description of Plumbing Hazards 
Contamination of the water supply by means of interconnections or 
defective plumbing fixtures may take place: (1) by the occurrence of 
a vacuum in the supply pipes causing back-siphonage of contaminated 
material, (2) by the development of a pressure in the fixture, appli- 
ance, or piping system to which the water supply is connected that is 
greater than that in the supply system itself, and (3) through the 
activities or actions of vermin, birds, or small animals in parts of 
the supply system not under pressure, or by dust reaching water- 
holding devices. 
A list of fixtures that might be considered hazardous to health would 
be very long. The development of various mechanical devices and 
appliances in which water is used as a primary or secondary function 
of the operation of the machine and the numerous industrial uses to 
which water is put have resulted in an exceedingly large number of 
different types of fixtures and plumbing appliances, some safe and 
others hazardous. Describing the most common fixtures in use today 
that may be considered as health hazards will suffice to illustrate, in 
all except a few instances, the essential features of a defective fixture 
or installation. Figures Ito 6 illustrate the most common types of 
fixtures encountered. 
Flush valve.—A very common interconnection which has been 
given too little attention in past years involves the simple flush valve 
on the siphon-jet type fixture. 
Satisfactory mechanical operation of most flush valves depends 
upon the maintenance of a continuous positive pressure in the water- 
supply lines. Should a vacuum occur in the supply line, the flush 
valve may open and back-siphon the fixture contents through the 
siphon-jet opening. It is not necessary for a siphon-jet fixture to 
be stopped-up in order for back-siphonage to occur. Even should 
the flush valve not open, a leaking valve would permit contami- 
nating liquid or material to pass back through it. 8 
OPERATION Or FLUSH -VALVES 
(A) under positive pressure 
Pressure on Liven ID trips 
VALVE (2) RELEASE S PRCSSURC IN 
CMAMBC R( S) ALLOW INC SUPPLY LINE 
PRESSURE TO RAISE DIAPHRAGM (OR 
PISTON)(4) PCRMITING WATER TO DIS- 
CHARGE TROU WATER SUPPLY LINE (6) 
THROUGH CHAMBER (7)INTO FIXTURE. 
AS WATER PASSES THROUGH PORTS 
(5) PRESSURE IS AGAIN BUILT UP IN 
CHAMBER (3) FORCING DOWN 01 A- / 
PHRAGM (OR PI STON) (4) WHICH CLOSES '' 
VALVE. 
(B) under negative head (vacuum) 
Should a vacuum occur in the 
WATER SUPPLY LINE (6) PRESSURE IN 
CHAMBER (3) IS RELEASED PERMITTING 
ATMOSPHERIC PRESSURE TO RAISE DIA- 
PHRAGM (OR PISTON) (4) AND FORCE 
FIXTURE CONTENTS THROUGH CHAMBER 
(7) INTO THE WATER SUPPLY LINE(«) 
AND THUS INTO ANY PORTION OF THE 
DISTRIBUTION SYSTEM. 
VALVC SEAT 
WATER 
SUPPLY 
LINE 
DIAPHRAGM TYPE FLUSH-VALVE 
VALVE,SEAT 
water 
SUPPLY. 
LINE 
PISTON TYPE FLUSH-VALVE 
SIDE-SPUD SIPHON-JET TOILET 
WITH FLUSH-VALVE 
Figure I.—Flush valves. 9 
INTEGRAL TANK 
8. BOWL TOILET 
DETAIL Or TANK WITH 
BALL COCK 8. FLOAT 
LOW TANK WITH 
SIPHON JET BOWL 
HIGH TANK WITH 
WASH DOWN BOWL 
Figure 2.—Flush tanks. 
218645—40 2 10 
Flush tanks.—To insure quietness of operation the inlets to flush 
tanks are almost always submerged. If the ball cock leaks or if it 
is opened for the purpose of filling the tank during a period of 
vacuum in the supply line, a portion of the tank contents may be 
back-siphoned carrying with it any pollution which may be in the 
tank. 
There are three types of flush tanks in general use for toilets: 
(1) the tank built integral with the toilet bowl, (2) the low tank, 
separate from the bowl, the outlet of which is usually two or more 
inches above the top of the bowl, and (3) the high tanks, most often 
used with a wash-down boAvl. 
With the integral tank there is so little difference in elevation of 
water in the tank and bowl that only partial stoppage in the latter 
will permit a mixture of the bowl and tank water. Such fixtures 
should therefore be considered deficient unless the tank-water inlets 
are adequately protected against back-siphonage. 
Low tanks are also subject to pollution by a mixture of the bowl 
contents with the tank water. For example, if a bowl stoppage oc- 
curs and a rubber force pump is used, a portion of the bowl contents 
may be injected through the siphon jet openings into the tank. The 
polluted tank contents are then subject to back-siphonage through 
the submerged inlet in the tank. 
If the cover of an integral or low tank is airtight, or nearly so, 
it is possible for the bowl contents to be drawn from the bowl through 
the tank into the water supply lines, if the tank inlet orifices are sub- 
merged or unprotected against back-siphon age. 
The possibilities of back-siphonage from a high tank to supply 
lines are quite as great as in the case of the low and integral type 
tanks. High tanks are usually open and consequently are subject 
to air pollution but other possibilities of contamination exist, such 
as by vermin or leakage from pipes passing above the uncovered 
tanks. 
Lavatories, bathtubs, and laundry trays.—These three fixtures are 
common to almost every home. A large percentage of them, as will 
be shown later, are supplied through submerged inlets. Most all of 
these fixtures have an overflow outlet at some distance below the 
rim, but so many conditions may occur to render this overflow useless 
that is should not be considered as a protection against back- 
siphonage. For example, in almost every installation of this type 
the overflow is connected into the drain line of the fixture at a point 
before the trap. Should the drain line become plugged beyond this 
connection it would render both the drain line and the overflow use- 
less as a means of disposing of the water in the fixture. Under such 
conditions it is entirely possible to cause the water to rise at least up 
to the spill line of the fixture thereby submerging the inlet. II 
LAVATORY 
LAVATORY 
'//'////////< 
BATHTUB 
BIDET 
LAUNDRY TRAY 
SINK WITH 
HOSt ON TAUCET 
SODA FOUNTAIN 
DENTAL 
CUSPIDOR 
ASPIRATOR 
Figure 3.—Other plumbing fixtures. 12 
Other common 'plumbing fixtures.—Soda fountain sinks, bidets, as- 
pirators, and dental cuspidors present more hazards than most of the 
fixtures with submerged inlets. As the inlets to soda fountain sinks 
and bidets are most commonly located at the bottom of the fixture, 
they are continuously submerged whenever the fixture is in operation. 
Aspirators are suction pumps, the power of suction being created 
by the rapid flow of water through a restricted opening at the point 
of attachment of the suction line. They are used to remove fluid 
contents of tumors and collections of blood during surgical opera- 
tions and saliva during dental operations, and as ejectors in handling 
fluids in chemical laboratories and waste wash water from washtrays 
and washing machines in homes. The principle is the same in each 
case and unless protection against back-siphonage is provided it is 
possible, when the discharge outlet is submerged, for contamination to 
reach the water supply. The dental cuspidor in figure 3is a partic- 
ular application of the aspirator principle. 
A very commonly found defect is usually man-made. It is best 
illustrated by the sink with an overflow outlet and a faucet, above 
the rim overflow line of the fixture, to which a short length of hose 
leading to the bottom of the sink has been attached. X-ray photo- 
graph and blueprint development trays, and arm and leg baths are 
variations of the same hook-up. It is also a defect almost always 
found in an autopsy room. 
Industrial equipment.—The application and use of water for indus- 
trial purposes has created a large number of different types of plumb- 
ing fixtures. Among the most common of these appliances are the 
laundry and dishwashing machines. In almost all of these installa- 
tions, the inlets are either submerged or become submerged when the 
machine is operated. The occurrence of a vacuum in the supply 
lines to these fixtures may cause back-siphonage of part of the contents 
of the devices. 
Hospital fixtures.—Bedpan washers and sterilizers may have a por- 
tion of their contents drawn into the water-supply line when a vacuum 
exists in the latter provided the inlet to the fixture is not protected 
against back-siphonage. 
The defects encountered in various sterilizer set-ups are similar 
and Figure 6 illustrates, hypothetically, the ones most often seen. The 
defects shown in this figure have been assembled from real installa- 
tions in everyday use in several hospitals. 
Figure 6 represents a sterilizer hook-up in about the worst light 
although other defects were found which are not shown. The fix- 
tures illustrated are in many cases old models and now out of date. 
The more modern hospital equipment has many improvements over 
the old, although some of the most modern pieces of equipment still 13 
01 SHWASHER 
LAUNDRY WASHING MACHINE 
Figure 4.—Dishwasher and laundry washing machine. 14 
BEDPAN WASHER AND STERILIZER (HOPPER TYPE) 
BEDPAN WASHER AND STERILIZER (VERTICAL TYPE) 
Figure 5.—Bedpan washer and sterilizer. ALL STEAM LINES OMITTED TOR THE SAKE Qf CLARITY 
A DIRfC T CONNECTION BETWEEN THE WATER 
A WASTE LINES EXISTS THROUGH THE COOLING 
COIL OP THE WATER STERILIZER IF VALVE -C IS 
OPEN AND VALVE-e IS CLOSED THE FULL 
PRESSURE OF THE COLD WATER SUPPLV WILL 
BE EXERTED AGAINST THE DRAIN VALVES OF 
ALL THE STERILIZERS IF ANT OF THESE VALVES 
SHOULD BE OPEN OR LEAK ONJTEHILE WATER 
AND ANY DRAINAGE THAT WAS IN THE KhNCH 
Waste line may be forced into* the 
STERILIZERS, CONTAMINATING THE CONTENTS 
AFTER STERILIZATION 
THE CONNECTIONS SHOWN ARE NOT FICTICIOUS 
THEY ARE ALL TAKEN FROM ACTUAL INSTALLATIONS 
THE CLOSING Of VALVE-6 WILL 
Cause the backing up or 
drainage in tme*£inch waste 
LINE. IF ANY OF TITE DRAIN 
VALVES ON THE STERILIZERS 
ABE OPEN OR LEAK THIS DRAIN- 
AGE MAY PASS INTO THE STERILIZER 
AND CONTAMINATE THE CONTENTS 
AFTER STERILIZATION 
HOT 1 C 04.0 W*T£* 
STEBIUZE* 
FLUSH VALVE OFFER 5 WO 
PROTECTION AGAINST BACA- 
SIPHONAGE OF CONTENTS OF 
BED PAN WASHERS STERILIZER 
INTO WATER LINE THROUGH SUB- 
MERGED SPRAY NOZZLES- IF 
DURING WASHING PROCESS, FOOT 
VALVE-A IS CLOSED THE SPRAY , 
NOZZLES MAY BECOME COMPCETtI/f 
SUBMERGED 
THE DIRECT CONNECTION OF THE V'NCH WASTE 
line FROM The STERILIZERS DIRECTLY INTO THE 
l-H-INCH WASTE LINE FROM THE SCRUB SINKS 
WILL PERMIT THE BACKING UP OF THE WASTE 
FROM THE SINKS INTO THE STERILIZERS IN THE 
EVENT OF A STOPPAGE IN THE SINK TRAP OR 
IN THE SOIL STACK 
AUTOCLAVE 
SUBMERGED INLETS TO UTENSIL i INSTRUMENT 
sterilizers may allow the contents or THE 
STERILIZERS, BEFORE STERILIZATION TARES PLACE, 
TO BE DRAWN INTO THE WATER SUPPLY LINE ICAuSE 
THE LATTER TO BECOME CONTAMINATED 
SCRUB SINK 
INSTRUMENT 
sterilizer 
OTZ MjtL .STftUZtff 
aeo pAM4incN5iL 
STtR.UZER 
EU 3H VALVE 
VALVE-C-» 
ste 
V Igencbator 
«*a VEMT 
4 WASTE 
wast! 
fr*AJTE 
I \ WASTE 
3 VENT 
I COLD WATER 
J ,y*LVE-» 
A DIRECT CONNECTION BETWEEN 
THE WATER AND WASTE LIMES 
EXISTS THROUGH THE STEAM 
GENERATOR OF THE AUTOCLAVE 
A VACUUM ON TH£ SURRLY LINE 
MAY DRAW CONTAMINATION INTO 
THE WATER LINE THROUGH THE 
STEAM GENERATOR 
A DIRECT CONNECTION EXISTS 
BETWEEN THE AUTOCLAVE AND 
THE WASTE LINE THE OCCURENCE 
OF A VACUUM IN THE AUTOCLAVE MAY 
CAUSE DRAINAGE TROM THE WASTE 
LINE TQ BE DRAWN BACK WTO THE 
AUTOCLAVE AND CONTAMINATE THE 
CONTENTS 
COLO WAT Eft 
NO BLEEDER LINE IS PROVIDED ON THE FILTER OF 
THE HOT AND COLO WATER STERILIZERS. THE 
OCCURENCE OFA VACUUM IN EITHER STERILIZER, 
TOGETHER WITH A LEAKING INLET MALVE AND AN 
OPEN OR LEAKING VALVE ON THE DRAIN OR INLET 
OF THE FILTER, WILL ALLOW UNSTCRILE WATER OR 
DRAINAGE TO BE DRAWN INTO THE STERILIZER AND 
CONTAMINATE THE LATTER 
A DIRECT CONNECTION BETWEEN THE WATER AND 
WASTE LINES EVIST3 THROUGH THE INLETANO 
DRAIN CONNECTIONS TO THE FILTER WHICH ARE 
CONNECTED TOGETHER AND ENTER THE FILTER 
AS OWE PIPE THE OCCURENCE OF A VACUUM 
ON THE WATER LINE MAY CAUSE CONTAMINATION 
TO BE DRAWN FROM THE DRAIN LINE FOR THE 
STERILIZERS INTO THE WATER SUPPLY THROUGH 
THIS CONNECTION. 
3JO'L LINE 
s' SOIL LINE 
TEE CONNECTIONS IN THE WASTE 
LINES AS SHOWN ARE CONDUCIVE TO 
■STOPPAGES IN THE BRANCH LINES 
THE Jj-INCH WASTE LINE IS NOT OF 
SUFFICIENT SIZE TO ADEQUATELY TAKE 
CABE OF THE DISCHARGES OF ALL OF 
FIXTURES CONNECTED TO IT THE 
SMALL SIZE OF THIS LINE IS LIKELY TO 
CAUSE STOPPAGES AND CONSEQUENT 
BACKING UP OF DRAINAGE 
4.'SOIL STACK 
HOSPITAL STERILIZING EQUIPMENT 
SOME IMPROPER DESIGNS AND INSTALLATIONS 
Figure 6.—Hospital sterilizing equipment. 15 
have defects due to improper installation or to the design of the fix- 
ture itself. Some of these are discussed briefly here. 
1. Improper design of equipment.—This may include the omission 
of a means of draining the gage glass and the tap of a water steri- 
lizer. If either of these two places contains nonsterile water after the 
sterilization process, the finished water may become recontaminated 
through contact with this small quantity of nonsterile water. 
2. Improperly designed vacuum breakers and air-breaks.—These 
may include {a) vacuum breakers with moving parts that are actu- 
ated only by the formation of a vacuum in the water line, (b) air gaps 
and vacuum breakers of insufficient size to furnish the air necessary 
to dissipate the vacuum, and (c) air breaks and vacuum breakers 
designed for use on high-pressure systems and installed on low- 
pressure lines, and vice versa. 
3. Bleeder lines, drains and overflow's submerged or directly con- 
nected to icaste lines.—Certain types of sterilizers are equipped with 
air breaks on the waste line. The drain line from the sterilizer may 
be submerged in the funnel or connected into the waste line below the 
funnel. The same may be true for bleeder or overflow lines. In any 
case, the purpose of the air break is defeated if any of the lines are 
submerged in the funnel or are connected to the waste line below it. 
4. Direct connection of cooling coil to waste line.—The cold water 
sterilizing unit is equipped with a cooling coil through which cold 
water passes to cool the water after sterilization. A number of instal- 
lations have this line connected directly into the waste line without an 
air break. This is a direct interconnection between the waste line 
and the water supply of the building. 
5. No bleeder line on filter or inlet valve.—The omission of a 
bleeder line from a filter or from an inlet valve may allow nonsterile 
water to pass into the sterilizer and contaminate the contents after 
the sterilizing process has been completed, 
6. Improper location of vacuum breakers and air breaks with 
respect to the fixture.—Insufficient height of the vacuum breaker 
above the highest possible water level in the fixture may cause even 
the best vacuum breaker to become ineffective. 
7. Changes in design of the fixture.—The use of modern fixtures 
and connections is no assurance against defects of installation and 
operation. Inspections of hospitals have revealed vacuum breakers 
and air breaks on the sterilizing equipment which have been taped 
ever to prevent noise and spitting. Proper design should forestall 
this eventuality. 
Miscellaneous.—The fixtures already described and illustrated are 
characterized by the fact that the important defect in practically 
all of them is the possibility of back-siphonage taking place result- 16 
ing in the contamination of the water supply. There are only a few 
fixtures in which contamination and disease may be spread without 
occurrence of a vacuum. Foremost among these is the drinking foun- 
tain. A joint report of the committee on plumbing of the American 
Public Health Association and the conference of State sanitary en- 
gineers {57) outlines the essential factors necessary for the construc- 
tion of a safe, sanitary drinking fountain which are as follows: 
1. The fountain should be constructed of impervious material, such as vit- 
reous china, porcelain, enameled cast iron, other metals, or stoneware. 
2. The jet of the fountain should issue from a nozzle of nonoxidizing, im- 
pervious material set at an angle from the vertical such as to prevent the return 
of water in the jet to the orifice or orifices from whence the jet issues. The 
nozzle and every other opening in the water pipe or conductor leading to the 
nozzle should be above the edge of the bowl, so that such nozzle or opening 
will not be flooded in case a drain from the bowl of the fountain becomes 
clogged. 
3. The end of the nozzle should be protected by nonoxidizing guards to pre- 
vent the mouth and nose of persons using the fountain from coming into contact 
with the nozzle. Guards should be so designed that the possibility of trans- 
mission of infection by touching the guards is reduced to a minimum. 
4. The inclined jet of water issuing from the nozzle should not touch the 
guard, and thereby cause spattering. 
5. The bowl of the fountain should be so designed and proportioned as to 
be free from corners which would be difficult to clean or which would collect 
dirt. 
6. The bowl should be so proportioned as to prevent unnecessary splashing 
at a point where the jet falls into the bowl. 
7. The drain from the fountain should not have a direct physical connection 
with a waste pipe, unless the drain is trapped. 
8. The water supply pipe should be provided with an adjustable valve fitted 
with a loose key or an automatic valve permitting the regulation of the rate of 
flow of water to the fountain so that the valve manipulated by the users of 
the fountain will merely turn the water on or off. 
9. The height of the fountain at the drinking level should be such as to he 
most convenient to persons utilizing the fountain. The provision of several 
steplike elevations to the floor at fountains will permit children of various 
ages to utilize the fountain. 
10. The waste opening and pipe should be of sufficient size to carry off the 
water promptly. The opening should be provided with a strainer. 
The use of several types of household filters for the purpose of 
providing a cleaner supply of drinking water often results in the 
deterioration of the quality of the delivered water. Unless rigid 
control is maintained over the cleaning and sterilizing of the filters 
their use should be discouraged. Reference will be made to the 
change in the quality of the water passing through such filters in a 
later chapter. 
Another source of contamination is through the improper location 
of soil and waste pipes with respect to water storage tanks and food 
handling and ice manufacturing equipment. The location of a soil 17 
or waste pipe over a water storage or supply tank makes possible 
the spread of contamination by leakage from defective pipes drop- 
ping into the tanks. The dropping of any of this contaminating 
material on food or food handling equipment will have the same 
effect. In ice manufacturing plants, the improper location of soil 
and waste pipes above the floor on which the water is frozen may 
permit leakage to drop into the ice cans and contaminate the ice. 
The use of open-top water supply and storage tanks is conducive 
to the entrance of dust and vermin with a resultant contamination 
of the water supply. 
Another fixture defect that has been brought to the attention of 
sanitary engineers and health officials recently is the standing waste 
in bathtubs and lavatories. While the chance for fixtures with this 
feature to spread contamination and disease is almost insignificant, 
there remains no justification for its installation and use, as the 
development of a safe and sanitary device of this type is both possible 
and economically sound. CHAPTER II 
DIGEST OF CORRELATED ACTIVITIES 
The activities of health, plumbing, and other organizations in con- 
nection with plumbing and public health touch upon several distinct 
phases of the problem including research, investigations, survey work, 
and remedial, corrective and preventive measures. 
For the publication of results of surveys, investigations, and re- 
search, thereby bringing before the plumbing industry, the medical 
and engineering professions, public health officials and the public 
at large, the hazards of defective plumbing and interconnections, 
much credit is due the plumbing trade journals and the several pub- 
lications of the professional societies. The trade journals of the 
plumbing industry have been very active in arousing the interest of 
the national plumbing organizations and the manufacturers of 
plumbing equipment to the necessity of properly designed and in- 
stalled fixtures. 
Research work in this field has followed varied courses such as the 
investigation into the prevalence of insanitary and defective plumb- 
ing fixtures in use or for sale at any time; the determination of the 
causes and effects of back-siphonage and vacuum formations and the 
frequency of vacuum occurrence; a study of the merits of various 
plumbing fixtures and protective devices and of the factors essential 
to the proper, safe and sanitary design of plumbing fixtures. 
Several individuals and organizations have spent considerable time 
and effort in research on these problems, and some of them have 
included, along with their research work, inquiries into the location 
of plumbing hazards together with proposals for correcting and pre- 
venting them. 
This chapter has been devoted to a summary of the information 
available on past and current work in this field. While this resume 
was intended to be complete, the authors regret that due to insuffi- 
cient information it was necessary to omit the results of a few investi- 
gations. 
The American Society of Sanitary Engineering has, for the past 
15 years, taken an active interest in the subject of interconnections 
particularly those related to plumbing fixtures and installations. The 
proceedings of that organization contain many articles and papers 
on this subject. These hazards were recognized and remedial meas- 
(18) 19 
ures and corrective programs were recommended by the society prior 
to the outbreak of amebiasis in Chicago in 1933. 
The Pasadena Water Department in 1932 {251) made a study of 
the possibilities of back-siphonage of toilet bowls equipped with flush 
valves. Results showed that under even small conditions of vacuum 
it is possible to siphon the contents of a jet-type bowl. Field tests 
by this department, January to May 1932, on vacuum formations in 
water mains during periods of shut-otf and drainage, indicate that 
appreciable vacuums will form for extended periods of time, some- 
times exceeding 60 minutes. The opening of a fire hydrant to relieve 
this vacuum does not prevent the formation of a vacuum in the build- 
ings supplied by the water main. 
The Fresno Public Works Department {283) sponsored several field 
experiments on three school buildings in which flush-valve toilets 
were located. All fixtures, with the exception of several of the flush- 
valve toilets, were shut off from the distribution system. These 
toilets were cleaned and a solution of fluorescin was placed in them. 
By simulating the conditions under which repair work was done and 
those existing when a fire occurred in the immediate neighborhood, 
the contents of the flush bowls were siphoned into the water supply 
as indicated by the recovery of the dye from other fixtures in various 
parts of the school buildings and from the street main. 
The National Association of Master Plwmbers has in the last few 
years evinced a pronounced interest in the subject of back-siphonage 
and interconnections. In October 1936, the association established 
a research program at the Institute of Hydraulic Research, State 
University of lowa, on the problem of back-siphonage and resultant 
pollution of the water supply. 
The conclusions of this investigation are given below :8 
1. Vacuum formations in water pipes cannot all be explained by analogy 
with the action of a simple siphon. Negative pressures in complicated piping 
systems due to a loss of pressure by friction may be very common. 
2. Polluted water from a few submerged inlet fixtures in biuldings can pol- 
lute the entire piping system in that building, and the pollution may also get 
back into the street water mains. 
8. Vacuums in pipe systems of buildings can be caused by negative water 
hammer pressure waves, local restrictions in pipes, and condensation of steam 
in hot-water tanks. 
4. The air flow through any given size opening into the pipes in which a 
partial vacuum exists will reach a maximum value when the vacuum is 15 
inches of mercury, and will not become greater with further increase in the 
degree of vacuum. 
5. A separate water supply to submerged inlet fixtures in a building cannot 
be considered as a practical and adequate elimination of water pollution 
8 Dawson, P. M., and Kalinske, A. A. “Report on Research.” Given before the Fifty- 
fifth Annual Convention of the National Association of Master Plumbers, Atlantic City, 
N. J., May 24—27, 1937, and by personal communication. 20 
dangers because: first, the cross-connection hazard is enhanced due to the dual 
water supplies, one safe and the other unsafe; second, it cannot be used for 
submerged inlet fixtures requiring a pure water supply and also for various 
hot-water fixtures. 
6. Installation of air inlets at tops of water risers and at various other points 
for purposes of vacuum prevention in water pipes is not the proper solution 
to the back-siphonage problem because: first, from a pneumatic standpoint 
entire prevention of partial vacuum formation by this means is practically 
impossible; second, air inlet devices installed under constant water pressures 
are entirely undependable. 
7. The correct and only solution to the back-siphonage problem is elimination 
and correction of the individual unsafe fixture. The unsafe fixture is the funda- 
mental evil in the plumbing system that makes back-siphonage possible, and 
therefore should be the point of attack. 
8. Inlets should be raised above the top of the fixture a distance equal to 
the value from one of the two formulas, (7=27) or (7=214 times the square 
root of A, where (7 is the gap in inches, D the diameter of water inlet, and A is 
the minimum area of the inlet. This will prevent any siphonage from such a 
fixture and will provide a substantial factor of safety. For common types of 
fixtures, the following heights of gaps are recommended: lavatory, 1 inch; 
kitchen sink and laundry trays, 1% inches; bathtub, 2 inches. 
9. Under certain conditions, as specified in this report, overflows leading from 
the fixture to the atmosphere may be considered as determining the maximum 
possible water level of a fixture, and the water-supply inlet need only be raised 
above the overflow. However, raising inlets above overflows which connect to 
the atmosphere, either directly or through an air gap in the overflow pipe, 
cannot be considered as an ideal solution by any means. 
10. The vacuum-breaking principle as defined herein has the necessary requi- 
sites for a proper solution to the back-siphonage problem. The proper appli- 
cation of this principle entails rigid requirements relating to the vacuum- 
breaking device used. 
11. It is recommended that the vacuum-breaking principle be accepted as a 
tentative standard for the proper solution to the back-siphonage problem if 
the vacuum breakers used meet all requirements specified in this report. It is 
further suggested that such vacuum-breaking devices, installed on actual instal- 
lations, be carefully observed for a number of years to note their performance 
characteristics before they are definitely accepted as standard. 
12. The tank closet with the constantly submerged inlet presents as great 
a back-siphonage hazard as any fixture in the plumbing system. Every effort 
should be made by manufacturers of closet tanks to have the entire float 
valve and water-supply piping connections installed above the overflow 
level of the tank if the tank water is subject to sewage pollution. Unless 
especially well designed, it is not recommended that moving part vacuum- 
breaking devices be used in closet tanks because of the corrosive conditions. 
13. Automatic flush valve fixtures should be protected from back-siphonage 
by incorporation of the following items: (a) a loose check valve to be incorpo- 
rated in the stop valve; (6) stable unit piston to be used if piston type valve 
is installed; (c) vacuum breaker between the control valve and fixture which 
meets specified requirements for vacuum breakers; (d) no water supply con- 
nection to a closet bowl below the flush rim of the bowl should be permitted. 
14. The frostproof closet presents such pronounced water-pollution hazards 
that its use even under the best conditions cannot be considered as satisfactory. 
15. A great many hospital fixtures are excellent examples of the water- 21 
pollution hazards that can be introduced in the design of various special fix- 
tures when important sanitary considerations are overlooked. 
16. Manufacturers of special water-supply and plumbing equipment and fix- 
tures should be ever alert regarding the introduction into the design of the 
fixture of back-siphonage hazards. Every attempt should be made to use 
the best solution to the back-siphonage problem; that is, “inlet above top of 
fixture.” 
17. The best program to inaugurate for the elimination of direct cross- 
connections with auxiliary private water supplies is the eliminating of the 
wholesale presence of such supplies in buildings served with the public water 
supply. Only when such auxiliary supplies are reduced to a minimum can 
regulations and inspections be entirely effective. 
18. Direct connection of city water to cooling and condensing systems used 
in gas compressors, refrigerating apparatus, and air-conditioning equipment 
should be condemned. Re-use of such water in the domestic supply systems 
of buildings is not satisfactory from a sanitary viewpoint. 
19. Submerged inlet water-supply connections to water used for air washing, 
cooling, humidifying, and dehumidifying should not be allowed. 
20. In buildings, water that flows in a pipe of considerable length under 
gravity, should never be used again in the domestic supply system. The 
chances of the pipe being used for a waste connection are too great. 
21. Tests indicate that the vacuum causing flow of air through rim ports 
of closet bowls and urinals, or through or over other surfaces likely to have 
polluted liquid drops adhering to them, should not be over 1 inch of water in 
order to prevent the picking up of polluted liquid droplets and the carrying 
back of such pollution in the form of a spray into the water-supply pipes. 
22. Most of the vacuums that occur in water pipes are caused by improper 
pipe sizing and by use of fittings and valves which introduce excessive friction 
loss. At least 90 percent of all vacuum formations could be prevented if 
water-piping systems were-sized and installed correctly. 
Following this research program, the directors of this association 
approved in November 1937 the establishment of a national plumbing 
inspection laboratory to be operated somewhat similarly to the Na- 
tional Board of Fire Underwriters’ laboratory. It is believed that 
the establishment of such a laboratory will do much toward the 
standardization of plumbing fixtures from the public health view- 
point, and the elimination of poorly designed and insanitary fixtures 
from the market. 
Since the adoption by the Wisconsin State. Board of Health of a 
State plumbing code in 1914, the board of health has taken an active 
interest in plumbing and its relation to public health. Research 
work to determine the possibilities of contaminating a water supply 
through the medium of defective plumbing fixtures and installations 
was carried out at the University of Wisconsin under the direction of 
the State board of health. A result of this work was the publication 
of a bulletin on interconnections in plumbing and water-supply sys- 
tems by that board in conjunction with the university officials. This 
bulletin gives a most complete picture of the hazards presented by 
defective plumbing fixtures and installations. 22 
Besides these investigative interests, the State board of health has 
revised its plumbing code to provide for the elimination and pre- 
vention of these public health dangers. Surveys for the location of 
existing defective installations have been and are being made and 
corrective action is being taken. Educational programs for the in- 
struction of plumbers and plumbing inspectors have been carried on 
from time to time. 
The National Bureau of Standards has conducted, during the past 
year, a research into interconnections in the plumbing of build- 
ings. A complete outline of the work done and the results obtained 
will be found in a recent publication {191) of that Bureau but an 
abstract of it is given herewith: 
This paper deals principally with the technical aspects of the problem of pre- 
venting the backflow of water from plumbing fixtures into water-supply systems. 
It starts with a general review of the subject, including a brief history of pre- 
vious work on the subject, a classification of cross-connections, and a brief dis- 
cussion of vacua and siphon action. This is followed by a mathematical and 
experimental analysis of the conditions tending to produce backflow into a 
supply line. This analysis makes it possible to determine the worst conditions, 
as regards backflow, that can occur in any building supply system, and to de- 
termine minimum requirements for the positive prevention of backflow under 
these conditions. Specifically, the minimum pressure that can occur in any 
system, the maximum rate at which water can be removed from the supply 
risers under this minimum pressure, the smallest air gap between a faucet and 
plumbing fixture that can be safely allowed under the worst conditions, and 
the essential performance characteristics of a siphon breaker are determined. 
The effectiveness of various types of siphon breakers in preventing backflow 
is discussed, and the operation of one type of flush valve is explained in order 
to show the essentials of a stable flush valve, that is, one which will not open 
under any possible reduction in supply pressure. Finally, there is given a brief 
review of the entire subject of preventing backflow from plumbing fixtures, in 
which two distinct methods of attack are pointed out, and the merits of each 
are discussed. The conclusions relate only to technical aspects of the subject 
and do not take the form of proposed health or plumbing regulations. 
In contrast to those organizations which have specialized in re- 
search work in the problem of back-siphonage and interconnections, 
others have devoted their efforts toward the location and determina- 
tion of the prevalence of this type of health hazard. This work was 
carried out through surveys of plumbing and plumbing fixtures. In 
some cases, representative buildings of various types were studied; 
in others, particular types of buildings were thoroughly gone over; 
while in still others, a number of buildings of all types were covered. 
A survey was made by the St. Louis Health Department of various 
hotels, swimming pools, pasteurization plants, and hospitals in Mis- 
souri for the purpose of ascertaining the extent of plumbing hazards 
to the public health. The scope and the plan of the survey were as 
follows: 23 
The work was undertaken as an F. E. R. A. project with a group of engi- 
neers of varying experience. It was planned to survey several buildings used 
for the following purposes: swimming pools, hotels, milk plants, and hospitals, 
since these probably represented the greatest potential hazard to the public 
health. While the entire program was planned on the basis of an investigation 
or demonstration, as required by the F. E. R. A., nevertheless, it was deemed 
necessary to do the work in a systematic thorough manner, otherwise many 
typical defects in the types of buildings chosen might be missed and the pur- 
pose of the survey defeated. Consequently, no attempt was made to cover a 
large number of buildings, but rather to survey thoroughly a few places 
representative of each of the several classes of structures chosen. (196) 
The following conclusions were drawn from the results of the 
work: 
(1) Past, and particularly more recent investigations of the danger to health 
from faulty plumbing within buildings indicate beyond a question of a doubt 
the responsibility, as well as potentialities, of such defects for causing such 
filth-borne diseases as dysentery and typhoid fever. 
(2) A survey of plumbing within representative types of buildings indicated 
that probably in all our cities many plumbing defects exist, which past experi- 
ence indicates will, under not unlikely circumstances, cause the dangerous 
contamination of water and food with the resulting exposure of individuals to 
pathogenic organisms. Further, this survey was sufficiently extensive to con- 
clude that the existence of such defects is prevalent in buildings used for 
numerous purposes and. undoubtedly, exists in buildings constructed for 
residential purposes, particularly the larger apartment houses. 
(3) Irrespective of the past or future jurisdiction of plumbing ordinances, 
this condition constitutes such a distinct and dangerous hazard to the public 
health that its control necessarily becomes a subject of grave importance to 
health departments, as well as water departments, and a responsibility which 
they cannot escape or delegate. (196) 
After the outbreak of amebic dysentery in Chicago in 1933, the 
Baltimore Health Department inaugurated an active interconnection 
prevention and elimination program which is still in effect. The 
program is here outlined in brief: 
1. The Baltimore city health department is vested by ordinance, with the 
control and installation of all plumbing. 
2. A reorganization of some of the department activities in 1932 made possible 
the development of the public health aspects of plumbing by establishing a divi- 
sion of plumbing in the bureau of environmental hygiene. 
3. A training course in the fundamental principles of public health with 
particular emphasis placed on cross-connections in defective plumbing was given 
the plumbing inspector staff. 
4. Attention of the plumbing trade was called to the regulations prohibiting 
potential cross-connections by circular letter informing them that the require- 
ments would be rigidly enforced. 
5. The installation of a small exhibit demonstrating the possibility of con- 
taminating the water supply as a result of potential cross-connections in plumb- 
ing systems was set up in one of the department laboratories for educational 
purposes. 24 
6. The inauguration of a program of reinspection of plumbing in all build- 
ings where considerable number of persons congregate or are employed such as 
hotels, hospital buildings, office buildings and industrial establishments. 
7. The inspection of and subsequent elimination of all cross-connections in 
swimming pools. 
8. Since the regulations pertaining to cross-connections in plumbing systems 
are not retroactive, corrections have been accomplished largely by educational 
methods. 
9. Careful review of all plans for plumbing by the chief inspector of plumbing 
in order to be assured that no cross-connections are included. 
The following table is an indication of the progress made since attention has 
been focused on the public health aspects of plumbing. Cross-connections elim- 
inated by the bureau of water supply of the department of public works are 
not included. 
Cross-connections prevented or eliminated in Baltimore 
Year: Number 
1933 195 
1934 * 282 
1935 436 
1936 973 
1937 1,669 
In connection with the reinspection of plumbing in buildings a careful check 
of the piping system and all fixtures is made. The number of types of poten- 
tial or actual cross-connections found are listed in order of relative importance 
and incorporated in a letter to the owner or manager of the building, explain- 
ing the situation and pointing out methods for correction. Follow-up visits 
are made for the purpose of pointing out and explaining the significance of 
the plumbing defects. This procedure has been found helpful in obtaining 
corrections.* 
In 1933 the San Francisco Water Department inaugurated a cross- 
connection elimination program. This study was supplemented by 
an investigation into the prevalence of plumbing defects as is ex- 
plained below; 
While the survey was being made to locate secondary sources of water supply 
it was noted that the water and sewer pipes in a good many buildings and 
industrial plants were cross-connected. Therefore, it was decided, upon the 
completion of the survey of other sources of water supply to continue the 
survey, working toward the elimination of cross-connections between water and 
sewer pipes and other possible sources of contamination within the piping sys- 
tem. This work was not completed due to a curtailment of funds, but the 
work as far as it was carried indicated that about thirty percent of the build- 
ings in downtown San Francisco had dangerous cross-connections between water 
and sewer pipes. In some cases sewage pumps, located in the basements of 
buildings, had a priming line connected to the pump in such a manner that it 
would be easily possible to pump sewage directly into the water piping of 
the building. Many buildings were connected with siphon ejectors in base- 
ment sumps to pump drainage water into the sewers and were so arranged 
that a vacuum in the water piping or a pressure in the sewage piping would 
force sewage into the water-piping system. 
9 Schulze, W. H. Personal communication. 25 
Many buildings equipped with fire sprinkling systems are served with a 
large connection for fire-protection purposes. The automatic fire system in 
most cases was arranged to be tested through a bypass around the alarm sys- 
tem, discharging directly into the sewer pipe. It is understood that the San 
Francisco fire department requires that the ammonia piping installed in refriger- 
ation plants be equipped with an outlet to the sewer for drawing off gas in case 
of breaks in ammonia piping. They also require that the ammonia piping be 
equipped with a water connection so that water may be sprayed into the 
ammonia piping dissolving the ammonia. In many cases these sewer, ammonia, 
water piping connections are close together, thus providing a direct connection 
between water and sewer lines. Should ammonia be present in the water pipes 
its high solubility could readily draw sewage into the water system. It is 
likely that at times of breaks, both water and sewer outlets would be open into 
the ammonia piping. Such times might readily be accompanied by a fire. This 
is an interesting case of conflict between the policies of the fire and water 
departments. Many buildings equipped with filters or water softeners were 
arranged in such a manner that the backwash line from the filter or softener 
discharged directly into the sewer pipe. A great number of plumbing fixtures 
were also found that had the water inlet pipes below the overflow level of the 
fixture. A number of pieces of hydraulicking equipment were found, arranged 
to utilize water pressure for washing or for a suction to remove wastes. All 
of these types of plumbing installations created a potential hazard to the 
purity of the potable water supply {66). 
Connecticut State Department of Health. 
In order to eliminate the chance of an outbreak of water-borne diseases sim- 
ilar to the amebic dysentery outbreak in Chicago in 1933, the Connecticut State 
Department of Health has begun an inspection program with the cooperation of 
local health departments. In cities where this program is carried out, it is 
expected that all buildings over three stories in height, all stores above one 
story, and all factories, hospitals, theatres, and hotels will be inspected. This 
group of buildings includes the jnost dangerous possibilities of building water- 
supply pollution, although theoretically it would be desirable to inspect every 
building. 
The survey in a city is suggested by the State department of health, and with 
the cooperation of the local health officer, an inspection form is arranged to assist 
the local inspector in carrying out the proposed program. A sanitary engineer of 
the State department of health accompanies the local inspector for two or 
more days at first to point out some of the undesirable conditions to look for. 
This is desirable in order to make certain the inspector understands the objective 
of the survey and is familiar with the more common systems to be encountered. 
Any unusual condition may be reinspected with the engineer of the State 
department of health. 
The local inspector carries out this work along with his regular duties. Addi- 
tional local inspection personnel is not usually available for this work with 
the consequence that a number of months may be required to complete each 
local survey. However, results are gradually being obtained. 
While proper protection of drinking-water storage or cooling tanks is the 
primary objective, leading questions are asked on the inspection forms used 
regarding other tanks, air conditioning, refrigeration, and other mechanical 
equipment in order to bring about the elimination of any cross-connections which 
may endanger the public water supply. These items are specifically covered by 
section (a) of the recently adopted regulation 127 of the State sanitary code 
218645—40 3 26 
entitled, “Minimum Requirements for Drainage and Toilet Systems” which, 
follows: 
“Plumbing and drainage systems shall be so constructed as to 
avoid contamination of safe drinking-water supplies in houses or 
buildings. There shall be no cross-connections between such safe 
water supplies and unsafe water supplies, nor shall such safe sup- 
plies be piped to refrigeration, air conditioning or other mechanical 
equipment provided with direct connections to drains or constructed 
in such a manner as to permit contaminated water to be siphoned 
or drawn into the water-supply pipes. 
“Storage of drinking water in buildings shall be only in covered 
tanks so constructed as to avoid any possible contamination of the 
water in the tanks. Sewer or waste lines located above storage 
tanks and direct overflows and drains to sewer systems are expressly 
prohibited.” 
Surveys are now under way in Hartford, New Haven, Bridgeport, New Britain, 
and Waterbury. These cities include all Connecticut cities with populations of 
more than 50,000 as indicated by the census of 1930. It is expected later to 
extend the survey to include towns and smaller cities. 
The first local survey was started in Hartford in March 1937 and no other 
survey was attempted until the procedure followed in Hartford proved satis- 
factory. New Haven next undertook this work to be followed more recently 
by Bridgeport, Waterbury, and New Britain. 
From March through December 1937, the Hartford board of health inspected 
96 buildings. Of this number, 23 were found to have drinking-water tanks. 
At 10 locations, about 10 percent of the places inspected, these tanks were not 
adequately safeguarded against possible contamination. The buildings thus far 
inspected include most of the larger ones and therefore those most likely to 
have tanks. 
In the course of the Hartford survey, two drinking-water cooling tanks were 
found which were not covered and were located directly beneath sanitary sewer 
pipes. Fortunately, these pipes were tight, but any leakage would have polluted 
the drinking water. Both of these conditions have been eliminated; one by the 
removal of the sewer line and provision of tight covers, and the other by the 
abandonment of the old cooling system and the installation of individual electric 
fountain coolers. The discovery of even one such condition would seem to war- 
rant: the time expended in these surveys. 
Thirty-three of the 96 places mentioned were found to have tanks storing 
water for purposes other than drinking. Some of these tanks had submerged 
inlets, or inlets that might be submerged, thus permitting the suction of water 
from the tank into the water-supply piping should a vacuum occur in the latter. 
Vacuums sometimes are formed by excessive draft or a water-main break. 
Several direct connections to sewers from water lines through refrigeration and 
air-conditioning equipment have been found in the Hartford survey. 
In all cases building owners or managers have been willing and even anxious 
to make any desired improvements after the hazards have been explained. Not 
all of the necessary reinspections have been made in Hartford as yet, but the 
improvements already obtained are very gratifying. 
It is possible that conditions in other cities will be found similar to those in 
Hartford, and that improvements will as readily be obtained. When all of 
these surveys are completed, many dangerous possibilities of water-supply pol- 
lution will be eliminated. The surveys indicate the need not only of delivering 
safe water to buildings, but also of keeping the water safe after it enters build- 
ings. {266) 27 
Besides research and survey work, many agencies have attacked 
the problem of back-siphonage by drawing up new plumbing codes or 
by making changes in existing codes, prohibiting the installation 
of disapproved plumbing fixtures and interconnections. Some of 
these codes are negative in character and prohibit any connection 
through which contamination of the water supply may occur. Other 
codes are more constructive in nature and require that certain defi- 
nite stated precautions be observed in the installation of plumbing 
fixtures. These precautions have been developed as a result of re- 
search work in this field. In the majority of cases, the plumbing 
codes or revisions as adopted by the various states or municipalities 
are not retroactive and no provision is made to cover defective instal- 
lations and fixtures already in place. 
The State Board of Health of New Hampshire {190) adopted as 
of March 9, 1938, several rules and regulations regarding plumbing. 
These rules are most explanatory in regard to public health aspects 
of plumbing fixtures and installations. Very clear and concise defini- 
tions of cross-connections and interconnections are given. Ain ini- 
mum allowable air gap between the highest possible water level in 
the fixture and an inlet is prescribed. 
Not only are inter- and cross-connections prohibited in future 
work, but all existing installations in hospitals, laundries, places 
where processing water and chemicals or either are used, schools, edu- 
cational buildings, and all other buildings of four stories and over 
are required to meet the specifications of these rules and regulations. 
New Bedford (Mass.) Water Department.—Having found by in- 
spections made in answer to complaints of poor water pressure, a 
growing tendency for the consumer to install fixtures which might 
prove hazardous to the quality of the water supply and the public 
health, the water department of New Bedford, Mass., adopted a set of 
rules and regulations, effective June 1, 1935, governing the installa- 
tion of house piping. The following are some of the principal 
requirements: 
Plans of proposed new installations or alterations of existing systems must be 
submitted to and approved by the water department before starting work. 
All inside piping must be installed under the supervision of a master plumber 
except in plants where competent pipers are regularly employed and except that 
connections to hot-water heaters and similar equipment may be made by persons 
regularly engaged in installing such equipment; all subject to inspection and 
approval by the water board. 
All installations are tested under city pressure in the presence of our inspector 
before acceptance. 
It is required that the service be carried full size to the point where the last 
branch is taken off. Accessible separate shut-offs are required in the basement 
for each tenement and for each hot-water tank. 28 
Concealed piping, tanks, etc., must be properly protected against freezing and 
must be tested before being concealed. The bottom of flush tanks for water 
closets or urinals must be above the overflow level of the fixture when the drain 
is obstructed. 
All flushometer valves must be equipped with a vacuum breaker of approved 
type. 
When the water is delivered to any receptacle below the overflow line of the 
receptacle when the drain is plugged, it is required that provision be made to 
prevent back-flow from the receptacle, by siphon breaker, check valve, or other- 
approved method (270). 
Maine State Department of Health and Welfare.—The bureau of 
health on June 1, 1926, adopted a plumbing code, setting forth mini- 
mum requirements for plumbing installations in the State of Maine 
and, at that time, provided for protection against contamination of 
water supplies through faulty plumbing. These regulations were re- 
vised on June 23, 1931, and on September 26,1934. The final revision 
prohibits the installation of any connection by which the water supply 
may become contaminated. Section 82 of the revised code reads as 
follows : 
Water supply pipe connections to swimming pools, hospital sterilizers, bedpan 
sterilizers, toilets, urinals or to any other plumbing fixture shall be made in a 
manner so as to make impossible the return of any of the water, liquid or waste 
from the swimming pool, sterilizer, toilet, urinal or other plumbing fixture to 
the water-supply distributing system either by gravity or syphonage. 
In addition to the above, the State laws require the submission of 
plans for all new school buildings or repair work in such buildings, 
and for the last 2 years before such plans were approved it has been 
required that all water closets equipped with flush valves shall be 
provided with approved vacuum breakers.10 
Kohler Corporation, Rochester, Minn.—The following corrective 
and preventive measures are applied to all of the establishments 
owned and operated by the Kahler Corporation. This corporation 
owns and operates several hospitals, cafeterias, laundries, dormitories, 
and hotels. 
Lavatory faucets should he provided with a gap of % inch between the lip of 
the faucet and the rim of the lavatory. 
Bathtubs should he provided with the same gap between the faucet and the 
rim of the tub. 
Closets should be.of the tank type and the filling tube should be above the 
water line in the tank; that is, above the overflow point. 
Steam tables should bo fed with water by means of an over-the-rim faucet. 
The drain for these should empty into an open pot trap. 
Sinks should be provided with over-the-rim feed. 
Dishwashers should be supplied with water by means of a faucet that is higher 
than the overflow point—about % inch. 
10 Campbell, E. W. Personal communication. 29 
There should be a distinct break in the water line before supplying potato 
peelers. 
Water fed to condensers should, upon leaving the condenser, be emptied into 
an open pot trap. 
A sitz bath should be fed. preferably, from a faucet over-the-rim of the tub 
above the overflow point of the bath. (If this is not possible a device may be 
arranged whereby the water empties into a standpipe a foot or so above the 
bath.) This standpipe feeds the sitz bath below the rim and this same stand- 
pipe, being open at the top, provides a vent to eliminate all possibility of back- 
siphonage. 
Continuous flow baths should be handled the same as sitz baths. 
Bidets should be fed from an open hopper. This hopper should be of a height 
to provide the proper water pressure. The break in the continuity in this case 
would be between the water line and the hopper. 
Instrument and utensil sterilizers should be supplied with water by means 
of a swinging over-the-rim faucet. In this case, the faucet must be swung out 
of place before the cover of the sterilizer can be lowered. The waste line from 
the sterilizers should empty into an open pot trap. 
It is satisfactory to supply a water sterilizer direct but when the water leaves 
the sterilizer, it must be provided with a break in the continuity. The waste 
line should empty into an open pot trap before reaching the sewer. 
All water suction devices or aspirators are a hazard and all new installations 
should provide suction by means of a vacuum pump. A vacuum pump and 
receiving tank should be located some place in the building and each room 
piped to this vacuum tank. When the suction is used, a receiver is installed 
in the room which collects any foreign matter in order to keep the suction sys- 
tem clean.11 
The American Water Works Association through its committee 
No. 8 on cross-connections lias made an extensive study of this subject. 
The committee presented to the association at Memphis, Tenn., on 
May 2, 1932, an exhaustive report. This was approved in 1933 by the 
committee on water works practice and published in the American 
W ater Works Association Journal of March 1933. 
The committee then presented to the association an additional report 
which was published in the journal of December 1936. It included a 
brief description of the types of cross connections which were involved 
in the outbreak of amebic dystenery in Chicago in 1933, a short 
resume of new regulations enacted, enforcement activities and experi- 
ences for the 2 years preceding the presentation of the report, and 
conclusions based on these incidents. 
On June 7, 1934, the following motions were adopted by the 
association: 
(1) That the recommendation of the committee on waterworks practice be 
adopted that the hotel where an American Water Works Association annual 
convention is to be held be required to submit a certified plan of their water 
supply and drain piping and a certificate from the State board of health in which 
the city is located that there are no dangerous insanitary conditions existing. 
(2) That the secretary, on behalf of the convention committee, he instructed 
to make a written report to the board on the sanitary conditions of the conven- 
11 Myrick, G. H. Personal communication. 30 
tion hotel to be presented at the time of the recommendation of the convention 
committee on choice of city and hotel. 
As a result of the adoption of these two motions, a committee on hotel 
sanitation was appointed, whose report was submitted to the association 
and approved by the board of directors, January 16,1986. This report 
was published in the journal of the association in February 1936, and 
defined more fully the requirements for certification of a hotel for use 
of the association in holding its annual meeting. (61) 
Detroit (Mich.) Department of Buildings and Safety Engineering.—During the 
course of the past year (1937) the department of buildings and safety engineer- 
ing of Detroit has installed a plumbing laboratory which includes a permanent 
demonstration installation, by means of which back-siphonage hazards may be 
shown, as well as having the facilities for testing fixtures, vacuum breakers, and 
other plumbing equipment for their efficiency of operation. 
This laboratory became available in November 1937. Since that time public 
health classes, senior architectural students from the University of Michigan, 
committees of plumbers, engineers, real-estate management representatives, sani- 
tary engineers, public health nurses, builders, and industrial representatives 
have seen the hazards that may be found in the present plumbing installations. 
Last April, as a result of certain preliminary studies that were secured from 
other municipalities and from our Detroit board of health, a bulletin was issued 
demanding that all water supplies be brought in above the rim of the fixture, 
the heights of the openings being dependent upon the size of the fixture 
supply. If the operation of the fixture was dependent upon a submerged sup- 
ply and it was not feasible to bring the supply above the rim of the fixture, it 
was requested that all such devices be equipped with vacuum breakers. This in- 
cluded ball cocks for tank-supplied water closets, lawn sprinkler systems, soda 
fountains and bar equipment, shampoo hoses, and other submerged connections 
as well as the flushometer-operated water closets. 
The effective date of this bulletin has been set forward at various intervals 
because the industry, in general, has no satisfactory vacuum breakers for some 
of the equipment. It finally became effective January 1, 1938. 
As rapidly as inventors found that facilities for testing such equipment were 
available they began bringing their ideas to be tested. As a result several ball 
cocks, equipped with vacuum breakers that are satisfactory have been found. 
The design of vacuum breakers for small supplies lias been aided by this means. 
A combination vacuum breaker and valve has very recently been accepted for 
installation in the city of Detroit, that protects against the possibility of back 
siphonage through lawn-sprinkling systems. 
At the present time work is being conducted on several types of vacuum 
breakers for flushometer supplied closets. A combination closet bowl and tank, in- 
vented by a local man, introducing a revolutionary principle for its flushing 
operation, has been tested in our laboratory and found satisfactory. It may 
appear on the market in the near future. 
An investigation is being conducted, at the present time, on dishwashing 
machines and the new type of automatic washing machines which are connected 
to the water and waste systems. 
A tentative study of a type of installation found in connection with air-con- 
ditioning systems is being made and so far only general recommendations, with 
reference to cross-connections have been made.32 
13 Shields, L. G. Personal communication. 31 
The Copper and Brass Research Association has contributed to- 
wards the education of health groups, plumbers’ associations, and 
various other related organizations to the dangers of defective plumb- 
ing installations. A motion picture illustrating the phenomenon of 
back-siphonage and the resultant contamination of the water supply 
has been made available by this association for educational purposes. 
The Massachusetts Department of Public Health in 1937 con- 
ducted a survey of several State institutions for the purpose of 
determining the prevalence of plumbing fixtures and installations 
which were capable of becoming a hazard to the public health and 
to the quality of the water supply. The results of this work showed 
that 1,066 fixtures out of a total of 3,525 inspected in 5 State insti- 
tutions contained either cross-connections or submerged inlets and 
were capable of allowing back-siphonage to occur under certain 
conditions. 
As a result of this study, the committee making it recommended the 
following; 
The State examiners of plumbers be authorized to establish rules and regu- 
lations relative to the construction, alteration, repair, and inspection of all 
plumbing work within the Commonwealth as provided in appendix XXIII of 
House Document No. 1200 of 1087 and that authority be extended to include 
all public buildings and public institutions except Federal buildings and Federal 
institutions (211). 
The Joint Committee on Plumbing of the American Public Tlealth 
Association and the Conference of State Sanitary Engineers pre- 
sented a progress report at a session of the public health engineering 
section on October 28, 1930. This report stressed the necessity for 
a further investigation into the relation between plumbing and public 
health and for a better control of the plumbing system by health and 
waterworks officials. It also included a final report on Essential 
Features in the Design of Sanitary Drinking Fountains which have 
already been discussed. 
Further progress reports of this joint committee presented in 
1935 and 1937 briefly summarized the work accomplished by various 
agencies in plumbing survey and research fields, together with the 
new developments in the plumbing industry, up to the time of pres- 
entation of the respective reports. 
The following is a resolution adopted by the Twentieth Annual 
Texas Water Works and Sewerage Short School at College Station, 
Tex., February 17, 1938: 
Whereas, the public health of the State of Texas has been and is being jeop- 
ardized by the installation of improperly designed plumbing fixtures and appli- 
ances, and 32 
Whereas, such fixtures and appliances are continuing to be marketed and 
installed throughout the State, and 
Whereas, no central or common agency exists for the impartial and compe- 
tent study, testing and approving of plumbing fixtures and appliances which 
would result in standardization and consequent savings to manufacturers and 
consumers alike, and 
Whereas, the A. & M. College and the State University are equipped or can 
successully and economically be equipped for the impartial and competent study, 
testing, and approving of plumbing fixtures and appliances and do further re- 
search work concerning the application of properly designed plumbing fixtures and 
appliances to the public health and formulate codes and standards for control 
and regulation of the design, manufacture, and installation of such fixtures 
and appliances: Now therefore be it 
Resolved by the Twentieth Annual Texas Water Works and Sewerage Short 
School that the State department of health give diligent thought and careful 
consideration to a plan or procedure of cooperation with either the A. & M. 
College, the University of Texas, or other State agencies in the establishment 
of a laboratory and sufficient competent personnel for the study, testing, and 
approval of plumbing fixtures and appliances and the formulation of codes and 
regulations for their design, manufacture and installation. 
Louisiana State Department of Health. 
In this department, for some time, particular attention was paid to the mat- 
ter of cross-connections in the work on inspection of water supplies and sewer- 
age systems. This activity is being extended to include inspections of piping 
arrangements at industrial plants. A number of inspections have been made, 
and a number of various types of cross-connections and arrangements which 
would permit back-siphonage have been found. To facilitate correspondence 
diagrams have been prepared showing representative defects and acceptable 
methods of correction. 
Lack of personnel prevents doing systematic work on plumbing inspection. 
Activity by local agencies is being promoted. Special attention is given to this 
problem by the plumbing division of the sewerage and water board of New 
Orleans, and all new work is required to be in order. It has not been possible 
yet to secure much change in old work except in public buildings and hotels. 
The Delgado Trades School, New Orleans, has cooperated by installing in 
the plumbing department of the school equipment for demonstrating the dangers 
of back-siphonage and for testing protective devices, such as vacuum breakers. 
The Baton Rouge water company at Baton Rouge has also installed a demon- 
stration set-up.13 
Minnesota State Department of Health. 
The Minnesota State Legislature, in 1933, passed a law which relates to the 
licensing of plumbers, the supervision and inspection of plumbing and the adop- 
tion and enforcement of minimum standards of the State board of health. Un- 
der the provisions of this act, all plumbers in municipalities with a population 
of 5.000 people or more are required to obtain a license issued by the State 
board of health. Examinations are usually held twice a year for applicants who 
are seeking either the master or journeyman’s license. 
The department of health drew up a plumbing code as authorized under the 
provisions of the 1933 law, and has since been recommending its adoption to 
municipalities throughout the State. In the original law, the code was set 
up as a mandatory document; in the amended law, passed in 1937, the board 
13 O’Neill, J. H. Personal communication. 33 
is given authority to make mandatory regulations on plumbing, but the board 
made a few minor changes in the code and adopted it again as an advisory 
code and is continuing to recommend its adoption through local ordinances. 
A good many municipalities have adopted the code in this manner, and many 
others have it under consideration. Although the code may not he adopted 
by all municipalities, however, State departments, the Works Progress Admin- 
istration and the Public Works Administration have agreed to require adherence 
to the code for all new plumbing installations under their control or subject to 
the approval of such governmental agencies. Plans and specifications for 
such projects are submitted to the Minnesota Department of Health for exami- 
nation before installations are made. One or more field inspections are made 
before the fixtures are installed, and then a final inspection is made after the 
installation of the fixtures and other equipment has been completed. 
Investigations have been made of plumbing in many buildings for the purpose 
of determining to what extent cross-connections exist, and to study the causes 
of pressure variations under normal operation in the water-supply system. 
The public health engineers in the large cities and those in the rural health 
unit districts of the State are at present making surveys of cross-connections 
in certain buildings in their respective cities and districts. 
The department of health, in cooperation with the hydraulics department of 
the University of Minnesota, has been doing research work on plumbing fix- 
tures and devices with the view of obtaining data which can he used as a basis 
for setting up minimum standards for their design and installation, the appli- 
cation of which should eliminate the possibility of contamination getting into 
the water-supply system. The equipment in the hydraulics laboratory has been 
arranged so that demonstrations can be given, and has been set up with plumb- 
ing fixtures and appurtenances commonly found in buildings and homes through- 
out the State. Such demonstrations have been given to many people who are 
interested in this phase of public-health work. 
For the purpose of conveying some of its findings and data obtained by 
research to those who are interested in this work but who are unable to visit 
the laboratory, the Minnesota Department of Health has developed some motion 
pictures and lantern slides of typical cross-connections, and these are being used 
extensively throughout the State as a means of educating people to the hazards 
of faulty plumbing design and installations. 
A bulletin has been prepared in which a number of sanitary plumbing fix- 
tures are being shown. Other data including that obtained from field investiga- 
tions and research work, are also presented.14 
El Paso, Tex. 
A modern plumbing ordinance was passed by the city of El Paso, Tex., which 
prohibits the installation of devices which may endanger the safety of the city 
water supply and embodies other regulations which are intended fur improving 
sanitary conditions from a standpoint of plumbing. 
This ordinance is now being placed in operation and many improvements in 
plumbing are being experienced. From time to time defective and inadequate 
plumbing which is a probable source of contamination is found and caused to 
be removed.15 
Houston, Tex. 
It has been found in surveying the several hospitals located in Houston, Tex., 
that very few of the instrument, water, and bedpan sterilizers were properly 
14 Whittaker, H. A. Personal communication. 
15 Carr, J. M. Personal communication. 34 
equipped to prevent back-siphonage into the drinking-wa’ter’ lines in tlie build-- 
ings. In one hospital a toilet bowl was found which was so equipped that bed- 
pans were washed by a submerged outlet in the toilet bowl which at all times 
constituted a cross-connection between both the hot and cold water lines within 
the building. 
The water department has worked closely with the plumbing inspection depart- 
ment in securing the installation of vacuum breakers on flushometer valves. 
The water and plumbing departments have an agreement with the Master’ 
Plumbers Association of the city to include the installation of approved vacuum 
breakers on all repair work done by them. Of course, all new flushometer valves 
installed as new have approved vacuum breakers built into the valve fixture. 
The exact number of vacuum breakers on new and old plumbing is not immedi- 
ately ascertainable, but it is estimated that more than 3,000 have been installed' 
within the last 3 years. 
Incidentally, the plumbing inspection department has constructed a dis- 
play to demonstrate the occurrence of back-siphonage in all types of defective 
plumbing equipment which cost in excess of $3,000 and is located in the city 
hall. This piece of construction has proven most helpful in demonstrating to 
building managers and owners the desirability of eliminating defective 
plumbing where possible.18 
In addition to the organizations already mentioned, there have been 
a number of individual investigators in this field. These have cov- 
ered several phases of the problem and have contributed much work 
of value. One investigation 17 worthy of note undertook to determine 
the prevalence of disapproved lavatories and bathtubs as exemplified 
by their having below-the-rim inlets, or standing or secret wastes. 
The results of this investigation, given in table 111, were obtained 
from a study of the catalogues of the various manufacturers of 
plumbing equipment and from actual inspections of the fixtures on 
sale in various salesrooms. 
Table lll.—Percent of fixtures surveyed and found unsatisfactory in regard to 
water inlet and drainage outlet 
Bathtubs 
Lavatories 
Firms 
Number 
Percent unsatisfac- 
tory 
Number 
Percent unsatisfac- 
tory 
surveyed 
Water 
inlets 
Drainage 
outlets 
surveyed 
Water 
inlets 
Drainage 
outlets 
A 
103 
78 
73 
B 
16 
69 
62 
C 
50 
16 
10 
54 
61 
0’ 
D 
163 
54 
45 
29 
78 
0 
0' 
E . 
34 
63 
65 
88 
69 
F 
10 
40 
60 
19 
63 
32 
G 
16 
50 
25 
32 
69 
6 
H 
4 
0 
0 
J 
26 
73 
62 
27 
55 
1 
K 
21 
100 
57 
64 
59 
0! 
L 
28 
72 
0! 
M 
4 
0 
0 
P 
23 
17 
0 
R 
28 
32 
O’ 
Total. 
H 
443 
396 
r 
Averages 
58 
50 
60 
3 
16 Harvill, C. R. 
17 Collins, Willis 
lished material). 
Personal communication. 
E., Thesis, Harvard Graduate School of 
Engineering, 1937 (unpub' CHAPTER 111 
SURVEY OF PLUMBING IN FEDERAL BUILDINGS IN NEW YORK AND 
DETROIT 
Joint resolution No. 254 was passed by the seventy-fourth Con- 
gress, first session, requiring the Public Health Service to make a 
survey of plumbing in all Federal buildings in the United States for 
the purpose of determining whether there existed any hazards to 
public health similar to those which were the cause of the amebic 
dysentery epidemic in Chicago in 1933. As no appropriation was 
provided to carry on the survey, this resolution was vetoed by the 
President. 
The Public Health Service was then asked to propose a project to 
the Works Progress Administration providing for a survey of plumb- 
ing in Federal buildings in the United States. At a conference to 
determine the extent of such a proposed survey, it was decided to set 
up a limited project to include only the Federal buildings in New 
York, N. Y., and Detroit, Mich. 
The number of supervisory personnel required for such an experi- 
mental project would be small and it would be practicable to give the 
special training required for technical employees before beginning 
the work. Methods of approach to and means of accomplishment of 
such a study, both unknown at the outset of the work, could be deter- 
mined more readily on a small project than on one encompassing the 
entire country. An opportunity would be presented to observe the 
suitability of Works Progress Administration beneficiaries for work 
of this character. It was believed, also, that the findings of a survey 
in two sample cities would be fairly representative of conditions 
existing in all Federal buildings and, to a certain extent, in all public 
and quasi-public buildings. The two major cities chosen were selected 
because it was believed that they presented the most likely oppor- 
tunity for obtaining Works Progress Administration beneficiaries 
suitably qualified to carry out the work. 
Accordingly, the Works Progress Administration, with the Public 
Health Service acting as cosponsor, initiated a project covering these 
two cities. Work was begun in May 1936 and continued until 
June 1937. 
(35) 36 
Organization of staff.—The working force was separated into three 
main divisions: (1) field inspections, (2) laboratory, and (3) admin- 
istrative and drafting. . 
The field inspection group was the nucleus about which the entire 
survey organization was constructed. Field parties performed the 
actual inspections, prepared the preliminary reports, and made the 
decisions as to whether or not plumbing fixtures and installations fell 
in the category of potential health hazards. The Works Progress 
Administration roll of relief recipients was lacking in personnel 
qualified to serve as field inspectors and it was necessary to select 
these men from nonrelief sources. The men chosen were, for the most 
part, recent graduates in sanitary or allied engineering courses. They 
were given 4 weeks’ training at New York University on the tech- 
nique of plumbing inspection, together with lectures on public-health 
hazards, cross-connections, back-siphonage, and water-borne diseases. 
Upon the completion of the training course the engineers were 
divided into six field parties each consisting of a chief of party, 
one or more engineers, from one to four plumbers, and from one to 
three handymen obtained from the work-relief roll. The six chiefs 
of party were selected from among the engineers completing the 
training course. Each supervised the operations of Ids field group, 
maintained the necessary link between the field and office forces and 
supervised and assisted in the writing of the preliminary field re- 
ports. The engineers, with the aid of the chiefs of party, inspected 
the plumbing and fixtures, prepared the field sketches and composed 
the field reports. The plumbers, handymen, and laborers furnished 
such assistance as was required. 
The laboratory personnel included a chief, several assistant bac- 
teriologists, and a number of attendants trained in the technique of 
proper water sample collection. This division cooperated with the 
field force in the collection and bacteriological examination of water 
samples taken from supplies in the various buildings inspected, and 
wherever the condition of the plumbing in a building warranted it, 
exhaustive tests were run. Limitations imposed on the work of 
the laboratory by the occupancy of the buildings and the necessity 
for continuous use of water restricted the laboratory’s usefulness 
to the project. 
The administrative and drafting division had in its drafting sec- 
tion a supervising draftsman and a number of draftsmen selected 
from the relief roll of the Works Progress Administration. These 
men, under close supervision and with the assistance of the chiefs 
of party, prepared' the finished drawings from the field sketches. 
The force of stenographic and clerical workers in the administrative 
section of the division under the guidance of the office engineer 
transposed the field notes into the final reports. These data, with 37 
the finished drawings and sketches, tabulations and photographs, 
comprised the finished reports for each Federal department which, 
after careful checking by the supervising engineer in charge of the 
project, were forwarded to the Public Health Service for transmittal 
to the respective department secretaries. 
The manner in which the stall' was coordinated is shown in fig- 
ure 7. 
Figure 7.—Organization chart. 
Scope of work.—While the scope of this project was limited to the 
Federal buildings in two cities, the large number of structures 
to be inspected necessitated the development of a simplified system of 
identification. This was accomplished by means of a group and unit 
scheme. Each separate group of structures in each of the two cities 
was given a group number. (For locations of the various groups, 
see figs. 8 and 9.) Each group was then subdivided by giving each 
structure in it a unit number. Plot plans of groups having more 
than one or two units were included in the reports to indicate the 
locations of the respective units. Throughout all of the work and in 
the final reports reference was made to buildings only by their group 
and unit assignment. In cases where more than one Government 
department controlled buildings in the same group, a subdivision of 
the group was made; as, for instance, group 2 and 2A. These sub- 
divisions were in turn divided into units to correspond with the other 
groups. Table IV gives, by departments in each of the two cities, 
the number of groups and units and the floor area of the structures 
in each department. 38 
NEW YORK CITY 
LOCATION Or GROUPS OP BUILDINGS INSPECTED 
GROUP LOCATIONS ARE INDICATED BY BLACK. DOTS 
Figure B.—Location of groups of buildings inspected in New York. 
LOCATION OF GROUPS OF BUILDINGS INSPECTED 
GROUP LOCATIONS ARE INDICATED BY BLACK DOTS 
Figure 9.—Location of groups of buildings inspected in Detroit. 39 
Table of structures and floor area 
'Department 
N umber of— 
Floor area 
Groups 
Units 
in square 
feet 
A 
1 
35 
645,375 
5,028,094 
2,046,271 
849,147 
156, 111 
460,000 
8,762,990 
'}) 
25 
25 
C - 
8 
62 
D . 
4 
5 
f. 
7 
34 
F 
1 
11 
,G 
10 
638 
56 
810 
17,947,988 
DETROIT, MICH. 
3 
45,183 
356,682 
427,786 
55,550 
185,155 
■B - - 
3 
3 
jc - 
3 
58 
D 
1 
8 
B 
2 
12 
12 
68 
96 
906 
1,070, 358 
19,018,346 
NEW YORK, N. Y. 
Table V classifies the buildings or structures (each being a unit 
irrespective of size, pse, or shape) in accordance with their height and 
floor area. 
Table V.—Structures classified by height1 
NEW YORK, N. Y. 
Number o,f stories 
Number of 
structures 
Percent of 
total number 
of structures 
Floor area 
in square feet 
Percent of 
total floor 
area 
1 . ... 
376 
46.4 
1,035, 738 
1, 755,308 
1,959. 178 
1, 772,820 
388,558 
10, 615, 399 
420.987 
5.8 
2 
104 
12.9 
9.8 
3 
193 
23.8 
10.9 
4 
43 
5.3 
9.9 
5 . .. 
9 
1.1 
2. 2 
17 
2. 1 
59. 1 
68 
8.4 
2.3 
DETROIT, MICH. 
1 ... ....... 
39 
40.7 
87,681 
47,176 
8.2 
2 
7 
7.3 
4.4 
3 
31 
32.3 
483, 393 
250,010 
132,438 
69, 660 
0 
4 ....... . 
15 
15.6 
23.4 
5 
3 
3.1 
12.4 
Over 5 
JJnclassifled 
1 
0 
1.0 
0.0 
6.5 
0.0 
l Basements and subbasements are counted as stories. 40 
Another differentiation of the structures has been made in table VI. 
Here they are shown in accordance with their use. While most of 
them are readily classified, a number, especially in New York, failed 
to fit under any general heading and have been listed as unclassified. 
Table Vl.—Classification of structures by use 
NEW YORK, N. Y 
Type of structure 
Number of 
units 
Percent of 
total number 
of units 
261 
32. 2 
.59 
7.3 
Office buildings 
32 
3.9 
28 
3. 5 
430 
53. 1 
DETROIT, MICH. 
Residences. 
32 
33.3 
Dormitories, multinle anartments. and barracks- _ . . . _ 
6 
6. 3 
Office buildings- 
12 
12.5 
2 
2. 1 
44 
45.8 
Report preparation.—To prevent the final inspection reports from 
becoming too large and thus being lessened in value, a simplified 
method of presenting the results of the work to each department was 
devised. This comprised: 
1. A general department report, presenting (a) a history of the- 
project, (h) the problem involved, (c) an outline of the inspection 
organization, (d) a short summary describing the order and method 
of presentation of the material collected, and (e) a general discussion 
of plumbing defects or deficiencies and health hazards with detailed 
explanations and illustrations of the more common defects. 
2. A list of groups of buildings under the jurisdiction of the depart- 
ment with an accompanying map showing the location of each group 
in the city. 
3. A brief group report, preceding the detailed unit reports of 
that group, containing information pertaining to the group as a 
whole. 
4. For all groups having more than one or two units, a list show- 
ing (a) the unit number used for the purpose of the survey, (b) the 
number assigned to the unit by those in charge of its maintenance, 
(c) the name of the unit, (d) its height, and (e) its approximate- 
floor area. 41 
5. A map showing the location of each unit in the group with 
the identifying unit numbers. Such a map was not prepared for a 
group consisting of only one or two units. 
6. The unit reports in numerical order. For larger units a com- 
plete description of the water and sewerage systems was given for 
a full understanding of the remainder of the report and following 
that, a summary of all plumbing defects separated into six general 
classifications. In small units it was possible to include all of the 
information on one sheet. 
In the larger units, defective fixtures were tabulated so as to 
show their location and with reference symbols to indicate the riser 
connection in the basement or pipe gallery feeding them. In the last 
column of the tabulation was given the type of defect or a reference 
to a detail drawing or photograph which, supplemented with ex- 
planatory remarks, further clarified the report. The commoner 
defects, repeated in many buildings, were explained in the general 
discussion of plumbing defects and mentioned only by name in the 
tabulation. 
When it was desirable to show complete piping lay-outs, isometric 
sketches giving all essential details and the reference symbols here- 
tofore mentioned were inserted at the end of the unit report. 
Summary of results.—In order to present the results of the survey 
in a simple yet complete form, two tabulations of the findings in each 
of the two cities were made. Table VII gives the number of fixtures 
inspected and table ATII the number disapproved for each type of 
building. (The term “disapproved” is used here to denote those 
fixtures which fall in the category of plumbing installations which, 
under certain conditions, may present a hazard to the public health.) 
It is impossible in this tabulation of results to qualify in any way 
the potential degree of danger attached to any of the fixtures. 
218645—40 4 Table Vll.—Number of fixtures inspected 
NEW YORK 
Type of building 
Fixture 
Resi- 
dences 
Dormi- 
tories, 
multiple 
apartments, 
and bar- 
racks 
Office 
build- 
ings 
Hospi- 
tals 
Unclas- 
sified 
Totals 
700 
1,220 
3, 062 
769 
928 
6,679 
4, 702 
701 
306 
662 
2, 483 
345 
906 
317 
77 
24 
47 
236 
81 
44 
195 
148 
123 
591 
1 
16 
1 
13 
17 
48 
596 
270 
5 
159 
49 
1,079 
690 
396 
231 
4 
20 
39 
420 
261 
154 
249 
374 
1,458 
136 
394 
190 
191 
311 
1,222 
8 
208 
1, 102 
115 
404 
1,837 
7 
82 
424 
180 
79 
772 
93 
424 
85 
88 
691 
3 
1 
49 
5 
4 
62 
111 
38 
28 
8 
42 
227 
1 
44 
11 
17 
73 
1 
28 
29 
1 
6 
3 
9 
2 
14 
3 
11 
1 
15 
5 
10 
9 
16 
1 
1 
2 
1 
3 
1 
1 
2 
2 
3 
2 
4 
5 
16 
5 
27 
8 
40 
3 
14 
8 
25 
3 
1 
14 
11 
29 
5 
1 
6 
3 
8 
11 
20 
20 
17 
17 
2 
2 
4 
3 
11 
2 
2 
167 
34 
20 
4 
59 
284 
5 
5 
io 
7 
8 
3 
5 
42 
1 
14 
15 
8 
38 
3 
31 
2 
36 
i 
44 
45 
17 
1 
18 
2 
17 
1 
20 
36 
36 
1 
i 
3 
16 
3 
24 
11 
5 
14 
30 
21 
22 
2 
45 
6 
6 
5 
14 
4 
23 
11 
13 
18 
42 
3 
3 
1 
25 
26 
1 
8 
9 
1 
2 
2 
5 
2 
4 
6 
1 
1 
1 
1 
2 
2 
1 
1 
1 
1 
1 
1 
1 
1 
1 
1 
4 
4 
7 
7 
1 
1 
3 
3 
3 
2 
5 
5 
46 
51 
3,276 
3, 676 
8,312 
2, 739 
3, 925 
21,928 43 
Table VII.—Number of fixtures inspected—Continued 
DETROIT 
Type of building 
Fixture 
Resi- 
dences 
Dormi- 
tories, 
multiple 
apartments, 
and bar- 
racks 
Office 
build- 
ings 
Hospi- 
tals 
Unclas- 
sified 
Totals 
116 
177 
567 
130 
11 
1,001 
454 
152 
20 
10 
150 
101 
134 
90 
191 
70 
109 
11 
79 
12 
Flushoinetcr closets 
33 
92 
94 
263 
46 
60 
6 
4 
8 
11 
8 
1 
8 
2 
106 
14 
30 
81 
19 
1 
67 
17 
14 
28 
8 
Showers .-. 
Urinals 
11 
5 
1 
38 
41 
10 
20 
132 
44 
18 
12 
15 
3 
1 
Drinking fountains _ - 
6 
13 
77 
10 
10 
4 
1 
54 
10 
11 
4 
11 
1 
3 
1 
1 
5 
Miscellaneous sterilizers 
Miscellaneous utensil washers. __ 
Miscellaneous machines. 
Water-sewrer connections. . ,. 
Cross-connections 
Pump priming lines .. 
3 
1 
1 
1 
9 
12 
Soup kettles. 
1 
1 
1 
Water filters ...» 
Vegetable conkers .. 
Bedpan washers 
2 
Water stills . 
Bar sinks 
34 
8 
8 
1 
3 
54 
Pressure ejectors . 
Suction ejectors . . 
4 
8 
1 
8 
3 
Bedpan sterilizers . . . . 
8 
8 
Water sterilizers . . .. 
3 
Instrument sterilizers. . . _ . ... 
2 
9 
9 
4 
Autoclaves .. 
4 
Cooling jackets . 
1 
2 
1 
Air conditioners 
Sitz baths . _ 
6 
6 
Potato peelers . 
5 
1 
1 
Coflee urns .... . .. 
1 
i 
i 
i 
Autopsy tables 
1 
Floor drains ... ... 
1 
Watering troughs. . 
Print washers . 
1 
' Soap melting pots 
Grease-removing tanks 
Lye vats 
Starch mixers 
1 
Lime boxes 
Water softeners. 
Paint stripping vats... 
Grease traps. ... ... .. . 
3 
3 
Swimming pools 
Material washers._ _. . 
Straddle stands 
Coding towers .. 
Coffee roasters . 
Printing machines.. 
Miscellaneous 
1 
1 
2 
Total 
623 
453 
1.238 
370 
52 
2, 736 Table Vlll.—Number of disapproved fixtures 
NEW YORK 
Type of building 
Fixture 
Resi- 
dences 
Dormi- 
tories, 
multiple 
apartments, 
and bar- 
racks 
Office 
build- 
ings 
Hospi- 
tals 
Unclas- 
sified 
Totals 
614 
1, 040 
662 
2, 664 
506 
741 
5, 565 
306 
2, 483 
345 
906 
4, 702 
317 
77 
24 
47 
235 
700 
81 
44 
195 
148 
123 
591 
1 
16 
1 
12 
17 
47 
468 
126 
5 
92 
35 
726 
248 
127 
4 
15 
19 
413 
11 
6 
7 
8 
25 
57 
2 
4 
245 
36 
15 
302 
1 
102 
32 
13 
148 
85 
1 
364 
82 
82 
1 
613 
1 
16 
19 
8 
2 
8 
10 
28 
i 
26 
9 
11 
47 
1 
28 
29 
5 
1 
6 
2 
1 
3 
3 
11 
14 
2 
5 
7 
2 
2 
i 
1 
2 
1 
3 
1 
1 
2 
2 
3 
2 
4 
3 
14 
27 
8 
40 
3 
6 
8 
17 
3 
11 
6 
20 
1 
6 
20 
20 
17 
17 
2 
2 
4 
1 
1. 
166 
34 
19 
4 
58 
281 
3 
3 
19 
7 
8 
3 
5 
42 
11 
34 
8 
33 
3 
31 
2 
36 
1 
44 
45 
16 
16 
2 
16 
18 
35 
35 
1 
3 
12 
2 
18 
11 
5 
9 
25 
21 
22 
2 
45 
6 
6 
3 
4 
1 
8 
4 
4 
3 
3 
1 
25 
26 
1 
1 
1 
2 
2 
5 
4 
4 
1 
1 
1 
1 
2 
2 
1 
1 
1 
1 
4 
4 
1 
1 
0 
2 
4 
5 
6 
11 
Total 
2,247 
2, 257 
6, 250 
1. 660 
2,430 
14. 844 Table Vlll.—Number of disapproved fixtures—Continued 
DETROIT 
Type of building 
Fixture 
Resi- 
dences 
Dormi- 
tories, 
multiple 
apartments, 
and bar- 
racks 
Office 
build- 
ings 
Hospi- 
tals 
Unclas- 
sified 
Totals 
113 
177 
553 
129 
10 
982 
33 
94 
263 
60 
4 
454 
91 
46 
6 
8 
151 
11 
8 
1 
20 
8 
2 
10 
99 
2 
15 
116 
67 
67 
1 
3 
1 
5 
6 
1 
7 
1 
1 
5 
77 
10 
4 
103 
2 
2 
2 
2 
6 
1 
3 
3 
1 
1 
3 
3 
1 
1 
1 
9 
12 
1 
1 
1 
3 
2 
2 
Boilers.. . 
34 
8 
4 
1 
3 
50 
1 
3 
4 
8 
8 
3 
3 
2 
2 
9 
9 
4 
4 
1 
2 
1 
4 
6 
6 
4 
1 
3 
1 
1 
3 
3 
1 
1 
2 
461 
298 
973 
284 
36 
2, 052 46 
From tables VII and VIII it can be noted that the number of fix- 
tures inspected in Federal buildings in New York and Detroit were 
21,928 and 2,736 respectively or a total of 24,664. The number of 
fixtures listed as disapproved in New York was 14,844 and in Detroit 
2,052, being respectively 67.7 percent and 75.0 percent of the plumbing 
installations inspected in the two cities. 
DISCUSSION OF CERTAIN PHASES OF SURVEYS 
In addition to the statistical results embodied in the preceding 
section, there are several conclusions that may be drawn relative to 
the carrying out of the survey itself. The extensiveness and com- 
pleteness of that survey permit comment on: 
(1) The suitability of Works Progress Administration beneficiaries 
for work of this nature, (2) the proper method of attack to be used 
in making a plumbing inspection survey, (3) the efficiency of the in- 
spection organization, (4) the desirability of recording results in 
the manner used in this survey, and (5) the value of the recorded re- 
sults as an indication of the necessity for a closer control of plumb- 
ing in various buildings. 
The Works Progress Administration was designed primarily to 
furnish gainful and creative employment for persons on relief. As 
such, it is essential for sound economy and effectiveness that the vari- 
ous projects undertaken furnish a maximum opportunity for the use 
of work-relief labor. The amount of work furnished by a survey of 
this nature is limited and the work is of such a character that it re- 
quires the employment of a number of specially trained men for its 
successful completion. These men must be able to understand and 
visualize the various factors influencing the conversion of a plumbing 
fixture into a health hazard. Men of the caliber necessary to satis- 
factorily conduct and carry out a plumbing inspection survey are not 
to be found, except in rare instances, on relief rolls. It is evident, 
therefore, that either the quality and accuracy of the survey results 
are reduced by the use of men from relief rolls regardless of their 
qualifications for the task, or else the essential purpose of work-relief 
projects is destroyed through the employment of nonrelief personnel 
to cany out the work. Since both of these alternatives are undesir- 
able, it is evident that a plumbing inspection survey of this nature 
is unsuitable for a work-relief project. 
Development of procedure.—lt was necessary at the start of the sur- 
vey to develop a tentative procedure to be followed in making the 
inspections. This tentative procedure was in the form of a ques- 
tionnaire (see Appendix A), the answers of which were to be the 
results of the inspection. Upon application of this method of re- Figure 10.—isometric view of sub-basement plumbing. 
U. S. GOVERNMENT PRINTING OFFICE : 1940—0-218645 47 
porting results it immediately became apparent that it was not com- 
prehensive enough in some cases and in others too cumbersome. As 
a result, the questionnaire was not used as intended but rather as a 
guide for the inspectors to follow. In this way, it proved to be quite 
useful and of instructional value. A procedure more applicable to 
the variable conditions encountered was consequently developed. 
This was outlined in a series of instructions issued to the engineers 
in the field (see appendix B) and it allowed considerable leeway to 
the various field parties in preparing their reports. 
The instruction sheet as issued provided for a most comprehensive 
report on the plumbing of all the buildings inspected. It was soon 
found, however, that the results obtained were not commensurate with 
the time and labor spent in following these instructions. Therefore, 
the procedure to be followed was again simplified by permitting ex- 
ceptions to that part of the instructions requiring complete drawings 
of all the plumbing systems, the exceptions to be made on the judg- 
ment of the chief of each party with the concurrence of the office 
engineer. This action speeded up the progress of the field parties 
to a measurable degree. As a further means of lessening the time 
necessary for making an inspection and recording the results, a pho- 
tographer was made available to the field parties to photograph 
special equipment thereby eliminating the need for a number of com- 
plicated and involved sketches. 
Drawings, sketches and photographs.—ln the larger buildings, a 
complete drawing of the water-distribution system in the basement 
or pipe gallery was required. This was considered essential to a com- 
plete understanding of the system and as a check on the progress 
and extent of the inspection work. The hazard presented by the im- 
proper installation of several fixtures is not always fully realized 
when only a visual inspection, fixture by fixture, is made. In several 
cases, a critical examination of the drawings of the water distribu- 
tion and sewerage systems in a building indicated the existence of 
a more dangerous situation than was revealed by the visual inspec- 
tion. For example, in one of the buildings in New York, the con- 
nection of a water line to a waste pipe through the cooling jacket of 
an ammonia condenser was observed. The hazard in this connection 
was based on the facts that a vacuum on the water line supplying the 
cooling jacket might cause contamination to be drawn from the waste 
pipe through the condenser and into the water supply or that a sur- 
charging of the waste line might cause contamination to be forced 
rather than drawn back into the water-supply line. It was not 
realized, however, until after the water and sewer piping had been 
sketched just how much danger was presented by the last possibility. 
A critical study of the drawings showed that the waste pipe into 
which the cooling water of the ammonia condenser discharged was, 48 
in reality, the discharge line from a centrifugal pump used to force 
waste water into a sewer at a higher level. Further, this discharge 
line was under a continuous positive pressure. 
Another illustration of the value of the drawings of a distribution 
system as an aid in comprehending what is happening to the water 
supply of a building can be explained by reference to figure 10. On 
this drawing, in about the center of the north side of the building, there 
can be seen two sewage ejectors and to the right and directly above them 
the two air compressors that supply the air to the ejectors. These two 
air compressors are equipped with cooling jackets supplied by a 1-inch 
branch from the water distribution system. The water, after passing 
through the cooling jackets, wastes into the discharge line of one of 
the sewage ejectors. The rated discharge pressure of the sewage 
ejector is 40 pounds per square inch whereas the water pressure at the 
meter is 45 pounds per square inch. 
On figure 10, the 1-inch water line can be traced back to its connec- 
tion with the main distribution pipe. Starting at the connection with 
the cooling jackets of the air compressors and tracing the line in the 
other direction the following branches from the 1-inch pipe are noted: 
1. C-46. 
2. C-43. 
3. C-44. 
4. Vacuum cleaner system. 
5. Line to cool bearing of fan. 
6. Line to water jacket. 
7. Connection to main distribution system. 
An examination of the report of the inspection party on this building 
showed that the following fixtures were located on the branches listed 
above: 
1. C-46—3 lavatories, 1 shower. 
2. C-43—1 lavatory, 1 shower. 
3. C-44—2 flush tanks, 6 urinals, 4 lavatories. 
4. Dust and wash tanks of vacuum cleaner system. 
5. Water-cooled bearings on fan. 
6. Water jacket on pump. 
In other words the 1-inch branch from the main distribution system 
in the basement serves 21 other fixtures besides the cooling jackets of 
the air compressors. With this many fixtures on this 1-inch line, the 
possibility of the water pressure in this line at the cooling jackets be- 
coming less than 40 pounds per square inch, the rated discharge 
pressure of the sewage ejector, is imminent. 
Figure 11 is a photograph of the plumbing hazard just explained. 
'On it the small line marked with an arrow is the 1-inch water line. 
It divides and goes to the cooling jackets of the 2 air compressors 
(covered line). Upon leaving the cooling jackets the 2 lines are figure 11.—sewage Ejector interconnection. 49 
again combined and are connected into the discharge line of sewage 
ejector No. 1 (line marked “S”). This photograph, while showing 
the actual hazardous connection, in no way indicates the presence 
of the 21 other fixtures connected to the 1-inch water line between 
this point and its connection with the main distribution system. 
This explanation shows that while photographs may serve to reduce 
sketching, it is important that they be used judiciously and not be 
permitted to take the place of drawings where the latter are obviously 
needed. 
Besides a complete drawing of the distribution and collection sys- 
tems of the larger buildings, it is often advantageous to prepare 
detailed sketches of special defects. These drawings may be simple 
line drawings on a large scale or they may be complete drawings of 
the machine or installation. The number and completeness of such 
drawings will depend upon the magnitude of the survey. Finished 
and accurate drawings of pumps, sewage ejectors, and other pieces 
of equipment and machinery, if found in a number of buildings, 
may be desirable for repetitive use. 
Figure 12 illustrates a sewage pump installation common to sev- 
eral buildings inspected in New York. The peculiar nature of this 
particular pump installation necessitated its illustration. The supply 
line to these pumps is open at all times so that the pump is primed 
continuously. As can be seen in the supplementary sketch on figure 
12, if a vacuum were to occur on the supply line, the water in the 
rotor chamber would be drawn back and a suction would be created 
in the pump chamber. As the level of the sewage rises in the cham- 
ber the float would rise opening the air break. If the float should 
stick or the air break be insufficient in size the sewage could be 
drawn into the rotor chamber and from there into the cold water 
line of the building. There is also the possibility of contamination 
being drawn back from the pump pit through the discharge 
line from the rotor chamber. 
Detailed descriptions.—ln addition to drawings, detailed sketches, 
and photographs, it is essential that a written description of the cold, 
hot, and drinking water distribution, the fire and sewerage systems 
be included in reports. These will assist materially in a better under- 
standing of the reports and of the many factors that may exert an 
influence upon the fixtures and installations in use in the buildings 
covered. 
The usefulness of such descriptions may be illustrated by an ex- 
ample taken from a report on one of the buildings inspected in New 
York. This building has several drainage sumps in the subbasement 
for collecting seepage water and one (a foundation well) is emptied 50 
Figure 12.—Suction sump pump. FIGURE 1 3.—Pr I MING LINE FOR CENTRIFUGAL PUMP. 51 
by the centrifugal pump shown in figure 13 forcing the seepage 13 
feet into the house drain at a point near the house trap. 
A branch from the main supply line taken off near the suction 
end of the house pumps is used to fill the suction leg of the centrifu- 
gal pump after repacking. With a vacuum on the water line and an 
open or leaky control valve, contamination may be drawn from the 
foundation well into the water supply of the building. Even with 
no pressure in the water line, the pump side of the supply valve may 
be subject to a head of 13 feet or more should the sewer back up 
through the centrifugal pump. That such a condition occurs is 
shown by an excerpt from the description of the sewerage system in 
that same report: 
It was learned that at times of high tide and with a northwest wind con- 
siderable backing up of the sewers is noted. Under such conditions neither the 
sewage ejectors nor the centrifugal pump (see fig. 13) can force the sewagei or 
drainage water into the house sewer. Valves on the sewer outlets are dosed 
and the sewage from the building is allowed to back up in the drains until the 
condition is relieved. 
As noted before, the methods employed by the field parties both in 
their inspections and in preparing their reports were such as to enable 
the office engineer to detect plumbing defects overlooked in the field 
upon a critical examination of the sketches, drawings, and descrip- 
tions handed in by a party chief. This valuable checking scheme 
proved its worth in several instances and, as a secondary result, 
brought about a clearer understanding of plumbing plans in the 
minds of those engaged in field work. 
The listing of the various defective fixtures found in a building by 
riser number, floor and room number, type of fixture, or installation 
of specific deficiency was intended to facilitate location of the various 
defects for purposes of checking or correction. This method of defin- 
ing the location of fixtures, especially when drawings of the distribu- 
tion system are included, is simple, requires little space, yet affords 
an accuracy almost as great as if the location of each fixture had been 
individually described. Modifications of this method may be made 
to fit any variable conditions encountered. For example, for build- 
ings where room numbers are not available, the location of the fix- 
tures on the various floors may be made by sections; the list of the 
defective fixtures to include a reference symbol indicating the location 
of the fixture on the particular floor as shown on a key plan of the 
building or on the drawing of the distribution system. 
Procedure for small buildings.—The foregoing discussion has per- 
tained principally to the inspection of large buildings, little mention 
being made of the procedure followed in small structures such as 
residences, small offices, storehouses, and shops. In these smaller 
structures, the piping systems are simple, the fixtures few in number 52 
and their location an easy matter. As a result, the inspection of these 
buildings may be accomplished in a short time. No drawings are 
necessary in most instances and photographs are not required except 
in special cases. 
Record of fixtures.—As an adjunct to the regular inspection report, 
a file card for each building was kept giving the total number of fix- 
tures of each type that were approved and disapproved and the total 
GROUP NO. 
NAME OF BUILDING 
UNIT NO. 
ADDRESS 
TOTAL NO. OF FIXTURES 
TOTAL NO. 
OF DEFICIENCIES 
TYPES OF FIXTURES 
NAME OF 
NO. 
NO. 
NAME OF 
NO. 
NO. 
FIXTURE 
APPR. 
DISAPPR. 
TOTAL 
FIXTURE 
APPR. 
DISAPPR. 
TOTAL 
LAVATORIES 
BOILERS 
FLUSKOMETER CLOSET 
PRESSURE EJECTORS 
LOW TANK CLOSET 
SUCTION EJECTORS 
HIGH TAJIK CLOSET 
DEVELOPING TANKS 
OTHER TYPE CLOSET 
DENTAL CUSPIDOPS 
BATH TUBS 
BED PAN STERIL. 
LAUNDRY TRAYS 
WATER STERIL. 
SINKS 
INSTRUMENT STERIL. 
SHOWERS 
UTENSIL STERIL. 
URINALS 
AUTOCLAVE 
SLOP SINKS 
COOLING JACKETS 
DRINKING FNTNSv 
AIR CONDITIONERS 
PUMPS 
SITE BATH 
H.W.STOR.TANK 
POTATO PEELERS 
TANKS (raSC.) 
COFFEE URNS 
Figure 14.—Plumbing survey file card. 
number of fixtures inspected. This card, illustrated in figure 14, is 
no more than a numerical summary of the results of the inspection. 
It has proven extremely helpful for many purposes and should be 
made a part of the inspection report procedure. Fixtures and instal- 
lations not appearing on the face of the card may be listed on the 
back. 
Recording progress of survey.—The progress made by the field 
parties was estimated by the square feet of floor area covered. Fig- 
ure 15 is a sample progress chart on which the total floor space for 
each department, estimated carefully at the start of the project, is 
shown under the heading of “total.” The progress of the field and 
the office work is figured on that basis and is listed under those head- 
ings. This method of recording progress was not entirely satis- 
factory, but no better substitute could be found for it due to the lack 
of information on the procedures to be followed in making a survey 
of this nature and of basic data such as are given in tables IX and X.. 
It was thought early in the survey that the size of the building would 
bear a certain relationship to the amount of plumbing to be inspected 
but this was soon found to be incorrect. A warehouse containing 53 
Figure 15.—Progress chart by Federal departments. 54 
little or no plumbing would have many times the floor area of a small 
office building and complicated and involved piping systems in power 
plants with a small floor area often necessitated a very intensive study 
of the different systems in order to complete the inspection. 
Table IX.—Average number of fixtures inspected per working-party-month in 
New York 
Working-party number 
Number of 
months em- 
ployd 
Number of 
buildings 
inspected 
Floor area of 
buildings in- 
spected in 
square feet 
Number of 
fixtures in- 
spected 
Average num- 
ber of fix- 
tures in- 
spected per 
month of 
employment 
1 .. 
13 
330 
2,791,353 
1, 360, 782 
6, 415,017 
2, 017, 939 
3,305,029 
2,057,868 
6,179 
2. 448 
3, 220 
4,501 
2,977 
2,603 
475 
2 
7 
45 
350 
3 . .. 
7 
155 
460 
4 
7 
244 
643 
5 
7 
16 
425 
fi _ 
7 
20 
372 
48 
810 
17, 947,988 
21,928 
457 
For future work of this description, a more accurate means of 
determining the efficiency and progress of a number of field parties 
would be to use as a measure the number of fixtures inspected. Data 
of this kind for each of the six field parties in New York are given in 
table IX. As the parties spent varying periods of time in the field, 
the number of months each party was employed is given. From the 
number of months employed, the average number of fixtures inspected 
per month has been calculated. 
TENTATIVE SURVEY ORGANIZATION 
FOR PLUMBING INSPECTION 
ORGANIZATION DESIGNED TO INSPECT A MINIMUM OP 3000 FIXTURES PER MONTH 
(for number of FIXTURES PER 1000 so ft of floor space see table x) 
Figure 16.—Survey organization for plumbing inspection. 55 
The average number of fixtures inspected per month per field 
party is fairly consistent although the number appears lower 
than might be expected. This latter condition is due to the com- 
pleteness with which the survey was carried out. In surveys of a 
similar nature it may be possible to increase the number of fixtures 
inspected per month by not requiring so much detail. 
Suggested organizatio7i for future surveys.—The organization as 
established for this plumbing inspection project was necessarily cum- 
bersome and less efficient than would be the case for a permanent 
organization. Figure 16 illustrates a tentative survey organization 
the composition of which has been based upon observations as to the 
value, ability, and function of the various individuals on the surveys 
in New York and Detroit and on the assumption that it would be 
a permanent organization. This group has been designed to inspect 
and report on a minimum of 3,000 fixtures per month. 
Personnel.—The duties and functions of the various members of 
this suggested inspection organization are as follows: 
Engineer.—The engineer is in complete charge of the inspection 
organization. He supervises the layout of the work, the writing of 
the finished reports, the making of the finished drawings and the 
filing and cataloging of all information. He arranges for the various 
inspections and assists in making recommendations for corrections. 
Assistant engineer.—The assistant engineer directs and supervises 
the work of three junior engineers. He receives the field notes and 
writes the final report on the buildings inspected. 
Junior engineer.—The junior engineer makes the actual field inspec- 
tions under the supervision of the assistant engineer. He develops 
the field notes and sketches and makes all recommendations for cor- 
rections to his immediate superior. 
Typists and draftsmen.—The typists and draftsmen under the 
supervision of the engineer and the assistant engineers make over 
the field notes and prepare the final reports. 
The office force consists of the engineer, two assistant engineers, 
typists and draftsmen. The two assistant engineers divide their 
time between the office and the field. The field force will be composed 
of the six junior engineers. 
As far as possible, each junior engineer will work as a separate 
field unit. In small buildings, one man can perform the inspection 
very handily; in larger buildings, the cooperation of two or more of 
the junior engineers and occasionally the assistant engineer may be 
necessary. 
Due to the administrative duties required of the engineer in charge 
of the inspection organization, it will be advantageous for him to 
direct the inspection in such a manner that his time in the field is 
reduced to a minimum. 56 
The qualifications of personnel included in this suggested organ- 
ization deserve considerable attention. With the exception of the 
draftsmen and typists, the members of a survey group should have 
a technical education and training or experience in the public health 
field. The training and education provided by accredited engineering 
schools permit the development of a more analytical insight into 
the problems encountered in work of this kind. Analysis of the 
factors influencing various fixtures and connections in a plumbing 
system plays an important part in arriving at satisfactory conclu- 
sions. The necessity for a knowledge of hydraulics, bacteriology, 
and sanitation and an understanding of the principles of the opera- 
tion of certain mechanical devices makes an engineering education of 
vital importance. By benefit of training in the public health field, 
an engineer is capable of exhibiting a broader view or conception of 
the problem than is possible in one lacking that experience. 
Measurement of progress and efficiency.—ln order to make possible 
an estimate of the amount of work capable of being performed by 
this tentative survey organization in some unit other than the number 
of fixtures inspected per month, table X showing the number of 
fixtures per thousand square feet of floor space for various types of 
buildings has been included. This table has been compiled from the 
figures given in tables IV and VIII. 
In making an estimate with the use of tables IX and X the com- 
pleteness with which the survey is to be carried on must be given 
adequate consideration for this exerts a marked influence upon the 
number of fixtures inspected per month by the survey organization 
and upon a final estimate of their capabilities. 
Table X.—Number of fixtures per thousand square feet for various classifica- 
tions of buildings, New York-and Detroit 
Type of building 
Number of 
buildings 
Floor area in 
square feet 
Number of 
fixtures 
Number cf 
fixtures per 
thousand 
square feet 
Residences., . 
293 
1, 202,104 
3,899 
3.2 
Dormitories, multiple-apartments, and barracks .. 
OS 
1, 140, 918 
4,129 
3.8 
Office buildings.. . 
44 
7, 644,281 
9, 550 
1.2 
Hospitals ... .. _ 
30 
1, 119,131 
3,109 
2.8 
Unclassified.. 
474 
7,911,912 
3,977 
.5 
Total. 
906 
19,018, 346 
24. 664 
1.3 CHAPTER IV 
SPECIAL INVESTIGATIONS IN CONNECTION WITH THE PLUMBING 
SURVEY OF FEDERAL BUILDINGS 
That more than a simple visual inspection of plumbing is often 
useful in a survey was demonstrated in the New York and Detroit 
work. In the final reports of the inspections no consolidation of the 
results of the investigation of various buildings in order to determine 
the hazard represented by the installation and use of defective plumb- 
ing fixtures in those buildings was attempted. There were several 
reasons for this but the principle one was the lack of information as 
to the frequency of occurrence of the factors influencing the danger 
presented by particular installations. The basis upon which a fixture 
was classed as approved or disapproved was solely the possibility of 
that fixture permitting the spread of contamination. The question as 
to how frequently contamination could be spread through the instal- 
lation and use of a fixture was not considered. It is imperative, 
before a logical conclusion can be drawn from the results of any sur- 
vey of this kind, that (1) the conditions which cause a fixture to be 
classified as hazardous, (2) the factors influencing these variable 
conditions, and (3) the frequency of occurrence of those factors be 
known. 
Probably the most important and necessary factor required for 
the spread of contamination through a plumbing fixture or instal- 
lation is the occurrence of a vacuum in the water line supplying the 
fixture. The devising of a means whereby all plumbing fixtures 
could be supplied with water under a positive pressure head at all 
times would eliminate the health hazard present in a majority of the 
disapproved fixtures in use today. The siphon breaker or vacuum 
breaker in use or on the market today is an attempt at this solution. 
The purpose of these devices is to prevent the vacuum from acting 
on the inlet to a fixture in such a manner as to eliminate the possi- 
bility of contaminated or waste material being siphoned into the 
water line. 
A major condition necessary for classifying a plumbing fixture as 
a possible means for spreading contamination is that the water or 
liquid drawn back into the drinking water line when back-siphonage 
occurs be of a quality inferior to that of the water supplied to fix- 
218645—40 5 58 
tures. Many excuses for the existence of interconnections have been 
made on the grounds that the water that might be drawn back into 
drinking water lines is not of a lesser quality than that of the water 
in those lines. An example of this is the use of water for cooling 
purposes in condensers where the water is intact in a closed piping 
system and the only change which takes place in it is a rise in tem- 
perature. The return of this water to the distribution system of a 
building or the existence of connections through which such a return 
would be possible are now considered dangerous. A noted example 
of the possible results of such a connection is explained in the de- 
scription of the outbreak of amebic dysentery in Chicago in 1933. 
Another condition that has been accepted until recently as presenting 
little hazard to water quality, should back-siphonage occur, involves 
the tank-fed water closet. Under normal conditions the water in a 
toilet tank should not deteriorate in any way nor should its quality 
vary from that of the water existing in the supply line to the tank. 
However, unusual conditions may occur to cause contamination of 
the water. 
QUALITY OF WATER IN OVERHEAD TANKS 
During the course of the plumbing survey in New York, a study 
was made of the bacteriological quality of the water in 20 overhead, 
open-top flush tanks in a comfort station. 
In this study 211 samples were collected by trained personnel in 
accordance with good sampling technique and were tested within 
2 hours after collection in a laboratory under the direction of a 
qualified bacteriologist to determine the number of bacteria per ml. 
growing on nutrient agar at 37° C. for 21 hours and the most prob- 
able numbers of coli-aerogenes group bacteria per 100 ml. The 
procedures followed were those given in Standard Methods of Water 
and Sewage Anatysis of the American Public Health Association 
(Bth edition, 1936) and the results were based on completed tests. 
The results of these tests are given in table XI. (For location of the 
various tanks see figure 17.) 
In this series of tests, no control sample to indicate the quality 
of the incoming water could be secured at a point sufficiently close to 
the overhead tanks. In lieu of this, the best average result recorded 
for any tank has been used to indicate the poorest possible quality of 
the incoming water. This result is that of tank No. 7 which had an 
average total bacteria count per milliliter of 31 and an average M. P. N. 
(coli-aerogenes determination) of 0.8 per 100 ml. The assumption 59 
NEW YORK CITY COMFORT STATION 
LOCATION OF OVERHEAD OPEN-TOP TANKS 
SCALE 
Figure 17.—New York City comfort station. Location of overhead open-top tanks. 60 
that the quality of the incoming water was not of poorer quality 
than that contained in tank No. 7 is made possible by the fact that 
the 20 tanks were all supplied from the same source and with the 
same water and that the samples from all 20 tanks were collected at 
the same time. 
Accepting the above assumption, it is therefore possible to state on 
the basis of the results listed in table XI that the water in the other 
19 tanks investigated showed evidence of a deterioration in quality. 
Such being the case, back-siphonage of the contents of toilet tanks 
whether high or low, open or closed, should not be countenanced. 
Table Xl.—Results of bacteriological tests of water samples from 20 overhead 
open-top tanks in a municipal comfort station 
No. of tank 
Num- 
ber of 
samples 
taken 
Average 
total 
bacterial 
count per 
milliliter1 
Average 
M. P. N. 
coli- 
aerogenes 
determi- 
nation 2 
No. of tank 
Num- 
ber of 
samples 
taken 
Average 
total 
bacterial 
count per 
milliliter 1 
Average 
M. P. N. 
coli- 
aerogenes 
determi- 
nation 2 
1 
11 
11 
2.4 
12 
11 
8 
3.1 
2 
13 
49 
5. 2 
13 
11 
13 
3.0 
3 
11 
81 
4.3 
14. 
11 
25 
2.8 
4 
11 
72 
1.2 
15 
11 
1,355 
2.7 
5 
11 
28 
5.7 
10 
11 
18 
2.4 
6 
11 
08 
3.5 
17 
5 
17 
3.3 
7 
11 
31 
.8 
18 
5 
14 
3.7 
8 
11 
16 
3.0 
19 
13 
10 
4.6 
Q 
11 
11 
11 
9 
24.4 
20 - 
10 
1,870 
2.8 
10. 
11 
10 
10 
3.7 
1.7 
20 tanks 
211 
185 
4.2 
1 Average total bacterial count per milliliter on agar at 37° C. for 24 hours. 
1 Average of the most probable number of coli-aerogenes group bacteria per 100 milliliters. 
FILTER STUDY 
Another application of laboratory facilities to the determination 
of the deterioration of the water supply quality through the installa- 
tion and use of certain plumbing fixtures was in a study made of the 
effect of certain small stone filters on the bacterial count of water 
passing through them {131). A total of 55 tests were run on 8 filters 
and the results indicated an average influent count of 51 and an 
average effluent count of 861 per ml. or an increase of 1,588 percent. 
The conclusion drawn from this study was that the water passing 
through these filter stones leaves most of its undissolved substances 
on the stones’ surfaces. These substances, apparently, are organic in 
nature as well as inorganic and provide any included bacteria with 
an abundant food supply. Multiplication takes place, and eventu- 
ally, if the stone is not replaced or cleaned, it becomes completely 
impregnated with bacteria. After that condition is reached, the 
filter stone gives off to the water passing through it more bacteria than 
it removes. 61 
VACUUM FREQUENCY STUDY 
Both of the preceding studies pertain to the deterioration of water 
quality through the installation and use of certain plumbing fixtures. 
Another study of interest is an investigation made subsequent to the 
completion of the plumbing inspection survey in New York. It 
was designed to determine the frequency with which a vacuum oc- 
curred or could be expected to occur in the water distribution systems 
of various buildings. 
Since no data were available on the vacuum frequencies of build- 
ings, a series of tests were run on six office buildings in New York 
to determine this information for these buildings and. also, to set up 
a method of procedure that might be followed in similar investiga- 
tions of other buildings. 
The plan first adopted in this study was to install an automatic 
pressure-vacuum recording gage at points in the buildings which were 
considered most likely to evidence a vacuum. Twenty-four hour pres- 
sure charts were obtained for each day until a vacuum was observed. 
It was soon realized that this procedure had certain definite limita- 
tions. In some buildings in which the gage was installed no vacuum 
was recorded even after a period of over 2 months. A procedure 
which required the investigation of each building for periods of 2 
months or more was definitely out of the question. Also, if a vacuum 
was observed to occur at some time in the building, the interval of 
time from the installation of the gage to the occurrence of the vacuum 
could be determined, but no record could be obtained for the interval 
of time between the occurrence of the vacuum that was recorded on 
the chart and the occurrence of the previous vacuum in that building. 
Therefore, the scheme of work was modified to permit the installa- 
tion of the gage for a predetermined period of time, the length of 
which would determine the accuracy of the result obtained. The 
charts from the building would then be used in developing a rough 
statistical analysis which would give an approximation of the actual 
vacuum frequency. This analysis consisted of tabulating, in order 
of magnitude, the lowest pressure recorded on the chart for each 
15-minute interval during the 24 hours. The frequency with which 
each pressure was recorded was determined and the percent of the 
observed pressures that were less than each stated pressure was cal- 
culated. This percentage was then plotted on both arithmetic and 
logarithmic probability paper against the values of the pressures 
observed in pounds per square inch. The extension of the curve 
obtained to intersect the line of 1 pound of pressure will give an 
approximation of the frequency of occurrence which can be expected 
for a pressure of less than 1 pound. Since it is possible to read 62 
only to the nearest pound of pressure on the gage charts and in order 
to read comparable results from the logarithmic plots (the logarithm 
of zero being minus infinity), a pressure of less than 1 pound has 
been considered to mean a pressure of zero or less pounds per square 
inch. The frequency of this occurrence has been considered as the 
vacuum frequency of the building, although it is really the frequency 
with which a vacuum can be expected to be recorded in a series of 
consecutive 15-minute low points. 
To permit a better understanding of the results of the various plots, 
the results obtained from the extension of the curves on arithmetic 
probability paper have been converted so that the length of time 
required in each building (in days) for a pressure of less than 
1 pound per square inch to be recorded is given. This conversion 
permits a more understandable comparison between the results from 
the various buildings. 
The procedure outlined above, while subject to several limitations, 
has the advantage of producing an approximation of the actual 
vacuum frequency that is based on scientific fact rather than pure 
conjecture. It also has the advantage of being simple in application 
and of not requiring a too extensive period of time for completion. 
In applying this method of procedure it must be remembered 
that the vacuum frequency obtained is for the point in the plumb- 
ing system at which the gage is installed. By installing the gage at 
a point in a building at which a vacuum is most likely to occur, it is 
assumed that the vacuum frequency obtained at this point will rep- 
resent the maximum vacuum frequency for the building. In other 
words, a vacuum will not occur more often in any other part of the 
building than it will at the point selected. 
The six buildings used for this study are referred to here as build- 
ings A, B, C, D, E, and F, the essential characteristics of which 
have been listed in table XII. They were selected because of accessi- 
bility, convenience of location, and dissimilarity of distribution 
systems. 
The length of time that the gages were installed in the six build- 
ings studied was much longer than was contemplated for the modi- 
fied procedure already outlined for the reason that a more complete 
and more accurate survey was desired. The time of installation 
varied in the six buildings from 2 weeks to over 2 months depending 
upon the building and the conditions observed. In several cases 
it was not possible to place the gage at the exact point desired 
because of limitations due to continuous operation of the buildings. Figure 18.—Typical Pressure Gage Installation. 63 
Table XIII shows the results as picked off the charts and arranged 
for plotting the curves on both arithmetic and logarithmic proba- 
bility paper. The plots of the curves for the various buildings on 
arithmetic probability paper are shown on figures 19-21. It will be 
noticed that no consideration has been paid to any of the points 
plotted on the charts except those at the lower end of the pressure 
scale. This has been done because no interest is attached to the 
upper end of the scale, the extension of the lower end being all that 
is required. 
Table Xll.—Essential characteristics of buildings included in vacuum study 
Name of build- 
ing 
Height of building 
Floor area in 
square feet 
Number 
of supply 
mains 
Size of sup- 
ply mains 
Average 
water 
pressure 
at meter 
in pounds 
per square 
inch 
Type of distribution 
system 
A 
12 stories and base- 
ment. 
Approximate- 
ly 75,000. 
Unknown 
Unknown. 
U nknown 
Overhead tank on roof, 
complete downfeed sys- 
tem, tank 30 feet above 
roof. 
B 
5 stories, basement, 
and subbasement. 
319,712 
2 
4-inch 
40 
Upfeed from hydropneu- 
matic tanks in base- 
ment. (90 pounds pres- 
sure from tank in day- 
time and 40 pounds 
pressure at night.) 
C 
33 stories and base- 
ment. 
655, 787 
2 
6-inch 
50 
Downfeed system from 
tank on thirty-third 
floor to all floors except 
basement. 
D 
8 stories, basement, 
and subbasement. 
142,500 
2 
3-inch 
55-60 
Downfeed system from 
tank on roof for second 
to eighth floors, inclu- 
sive. 
E 
8 stories, basement, 
and 2 penthouses. 
40,000 
2 
2-inch 
50-55 
Upfeed system to sixth 
floor; downfeed from 
roof tank to seventh, 
eighth, and penthouse 
floors. 
F 
9 stories, basement, 
and subbasement. 
Approximate- 
ly 500,000. 
2 
6-inch 
Unknown 
Downfeed system from 
tank on roof for third 
to ninth floors; upfeed 
to all other floors. Table Xlll.—Lowest pressures recorded in consecutive 15-minute intervals 
BUILDING A 
Pressure (pounds 
per square inch) 1 
Fre- 
quency 
of occur- 
rence 
Cumu- 
lated 
frequency 
Percent of 
observed 
pressures 
less than 
stated 
pressures 
Pressure (pounds 
per square inch) > 
Fre- 
quency 
of occur- 
rence 
Cumu- 
lated 
frequency 
Percent of 
observed 
pressures 
less than 
stated 
pressures 
1 
0 
0 
0.00 
14 
189 
962 
21.58 
2 
3 
3 
.00 
15 
220 
1,182 
26.86 
3 
3 
6 
.08 
16 
213 
1,395 
32.99 
4 
5 
11 
.17 
17 
262 
1,657 
38.95 
5 
12 
23 
.37 
18 
232 
1,889 
46.26 
6 
25 
48 
.64 
19 
206 
2,095 
52. 74 
7 
42 
90 
1.34 
20 
120 
2, 215 
58.49 
8 
56 
146 
2. 51 
21 
75 
2, 290 
61.84 
9 
67 
213 
4.08 
22 
74 
2,364 
63.93 
10 
110 
323 
5. 95 
23 
372 
2, 736 
65.99 
11 
127 
450 
9.01 
24 
608 
Si 344 
76. 38 
12 
154 
604 
12.56 
25 
238 
3, 582 
93. 36 
13 
169 
773 
16.86 
» 
BUILDING B 
-15 
2 
2 
0.00 
8 
7 
1,053 
29.93 
-14 
4 
6 
.06 
9 
9 
1,062 
30.14 
-13 
4 
10 
.17 
10 
19 
1,081 
30. 39 
-12 
8 
18 
.29 
11 
18 
1,099 
30.94 
-11,.. 
6 
24 
.51 
12 
14 
1,113 
31. 45 
-10 
6 
30 
.68 
13 
14 
1,127 
31.85 
-9 
3 
33 
.86 
14 
18 
1,145 
32. 25 
-8 
10 
43 
.94 
15 
17 
i; 162 
32. 76 
77 
120 
1.23 
16 
26 
1,188 
33.25 
-6... 
73 
193 
3.43 
17 
15 
1. 203 
33.99 
-5 
33 
226 
6. 52 
18 
25 
1,228 
34.42 
-4 .. 
24 
250 
6.46 
19 
22 
1, 250 
35.14 
-3. . 
115 
365 
7.15 
20 
127 
1,377 
35. 77 
-2 
292 
657 
10. 44 
21 
461 
1,838 
39. 40 
-1 
130 
787 
18. 80 
22 
878 
2,716 
52. 59 
0... 
67 
854 
22. 52 
23 
449 
3,165 
77.71 
1... 
122 
976 
24. 44 
24 
82 
3,247 
90. 56 
2 
21 
997 
27.93 
25 
33 
3,280 
92.90 
3 
11 
1.008 
28.53 
26 
44 
3,324 
* 93.85 
4 
12 
1,020 
28.84 
27 
42 
3,366 
95.11 
5 
12 
1,032 
29.18 
28 
69 
3,435 
96.31 
6 
7 
1,039 
29.54 
29 
11 
3, 446 
98.28 
7... 
7 
1,046 
29. 73 
30 
49 
Si 495 
98.63 
BUILDING C 
24 
1 
1 
0. 00 
29 
37 
584 
78.48 
25 
25 
26 
. 14 
30 
27 
611 
83.79 
26 
133 
159 
3.73 
31... 
6 
617 
87.66 
27 
293 
452 
22. 81 
32 
25 
642 
88. 52 
28 
95 
547 
64. 85 
33 
55 
697 
92.11 
BUILDING D 
-1 
2 
2 
0.00 
17 
43 
806 
19.80 
0—. 
6 
8 
.05 
18 
39 
845 
20. 91 
1 
26 
34 
.21 
19 
29 
874 
21.92 
2 
96 
130 
.88 
20 
28 
902 
22.69 
3 
106 
236 
3. 37 
21 
24 
926 
23.40 
4 
62 
288 
6.12 
22 
21 
947 
24.03 
5. 
36 
324 
7.47 
23 
23 
970 
24. 57 
6 
21 
345 
8.40 
24 
17 
987 
25.17 
24 
369 
8.96 
25 
29 
1,016 
25. 61 
8 
16 
385 
9. 59 
26 
27 
1, 043 
26. 36 
9 
29 
414 
9.99 
27 
31 
1, 074 
27. 06 
10 
40 
454 
10.74 
28 .. . 
28 
l' 102 
27. 87 
11 
35 
489 
11.78 
29 
. 31 
1,133 
28. 59 
12 . 
51 
540 
12.68 
30 
55 
i; 188 
29.40 
13 
59 
599 
14. 01 
31 . 
71 
1,259 
30.82 
14... 
59 
658 
15. 55 
32 
85 
l’ 344 
32. 67 
15 
54 
712 
17. 07 
33 
145 
l| 489 
34.87 
16 
51 
763 
18. 48 
34 
154 
1, 643 
38.64 
1 Pressures preceded by a minus sign are negative pressures and are expressed as inches of mercury vac- 
uum; 1 inch of mercury being equal to 0.4912 pounds per square inch. 65 
Table Xlll.—Lowest pressures recorded in consecutive 15-minute intervals— 
Continued 
BUILDING 
D—Continued 
Pressure (pounds 
per square inch) 
Fre- 
quency 
of occur- 
rence 
Cumu- 
lated 
frequency 
Percent of 
observed 
pressures 
less than 
stated 
pressures 
Pressure (pounds 
per square inch) 
Fre- 
quency 
of occur- 
rence 
Cumu- 
lated 
frequency 
Percent of 
observed 
pressures 
less than 
stated 
pressures 
35 
206 
1,849 
42.63 
142 
3,513 
87.47 
36 
222 
2,071 
47.98 
46 
143 
3,656 
91.15 
37 
201 
2, 272 
53.74 
47 . 
91 
3'747 
94.86 
38 
189 
2,461 
58.95 
48 
59 
3' 806 
97.22 
39 
168 
2,629 
63. 85 
49 
27 
3, 833 
98. 75 
40 
161 
2,790 
68. 21 
50 
12 
3,845 
99.45 
41 
143 
2,933 
72.39 
51 
6 
3i 85i 
99.77 
42 
149 
3, 082 
76. 10 
52 
2 
3j 853 
99.92 
43 
150 
3,232 
79.97 
53 ... . 
1 
3, 854 
99.99 
44 
139 
3, 371 
83.86 
BUILDING E 
1 
0 
0 
0.00 
13... 
90 
497 
20.94 
2 
2 
2 
.00 
14... 
170 
667 
25. 58 
3 
4 
6 
. 10 
15 .. 
194 
861 
34. 32 
4 ... 
10 
16 
.31 
16 
191 
1,052 
44.24 
5.. 
23 
39 
.82 
17 
214 
1, 266 
54.12 
6 
84 
2.01 
18 
91 
357 
65.12 
7 
52 
136 
4.32 
19... 
100 
1,457 
69.80 
8 
47 
183 
7.00 
20 . 
85 
1, 542 
74.95 
9 
36 
219 
9.41 
21 . 
232 
1, 774 
79.32 
10 
46 
265 
11. 27 
22 .. 
132 
1,906 
91.25 
11 
69 
334 
13. 64 
23... 
37 
li 943 
98.04 
12 
73 
407 
17.18 
24 .. 
1 
1,944 
99.99 
BUILDING F 
0 
0 
0 
0.00 
8 
16 
33 
0.65 
1 
1 
1 
.00 
9 .. 
51 
84 
1.28 
2. 
0 
1 
.00 
10... 
322 
406 
3. 27 
3 
6 
7 
.04 
11 
576 
982 
15.81 
4 
6 
13 
.27 
12 
450 
1,432 
38.21 
5 
1 
14 
.51 
13 
484 
li 896 
55. 72 
6 
0 
14 
.53 
14 
632 
2,528 
73. 77 
7 
3 
17 
.53 
15 
42 
2, 570 
98.37 
The results obtained by extension of the lower end of the curves 
are given in table XIV. The vacuum frequency is shown there as 
a percentage and is the same as read from the plots. 
From the results in table XIV it is seen that in two of the build- 
ings the frequency with which a vacuum might be expected to occur 
was not too small as to be insignificant. In fact, with the low pres- 
sures recorded in three of the buildings in which a vacuum was not 
actually observed to occur it is reasonable to assume, aside from any 
statistical analysis, that under more adverse conditions than were 
experienced during the period that the gage was installed, a 
vacuum might easily have been recorded. In only one building, C, 
can it be safely said that, under the conditions existing in the build- 
ing at the time the study was made and the normal operating con- 
ditions of the water system, and excepting all unusual and unpre- 66 
Figubb 19.—Building A 67 
FIGUKE 20.—Building B 68 
Figure 21.—Building C 69 
Figubb 22.—Building D 70 
Figure 23.—Building E 71 
Figure 24.—Building F 72 
dictable circumstances, such as breaking of pipes or draining of the 
distribution system, a vacuum might never be expected to occur. In 
the case of building B, a vacuum was observed to occur about 25 
percent of the time. The reason for this high percentage can be 
seen by referring to a typical chart record of building B as shown 
in figure 25. The sustained vacuum during the night in this build- 
ing was due to the shutting down of the house pumps as an economy 
measure. After the pumps were cut off, the pressure in the hydro- 
pneumatic tanks in the basement was gradually dissipated until it 
equalled the pressure from the street mains. This latter pressure 
was insufficient to keep the water in the vertical pipes up to the level 
of the fixtures on the fifth floor. As a result a sustained vacuum 
was created until the pumps were again turned on. 
Table XlY.—Results of study of vacuum frequencies of 6 New York office 
buildings 
Name of 
building 
Num- 
ber of 
obser- 
vations 
Lowest recorded pressure 
Vacuum frequency 1 
(percent) 
Vacuum ex- 
pectancy 2 
From arith- 
metic- 
probability 
plot 
From log- 
arithmic- 
probability 
plot 
A 
B 
C 
D 
E 
F.._ 
3, 582 
3, 495 
697 
3, 854 
1,944 
2,570 
2 pounds per square inch 
15 inches of mercury vacuum. .. 
24 pounds per square inch 
1 inch of mercury vacuum 
2 pounds per square inch 
1 pound per square inch 
0.013 
25 
Negligible 
0, 24 
0. 0051 
0.015 
0.0037 
25 
Negligible 
0. 23 
0.0021 
0.0038 
80 days. 
0.042 days. 
Incalculable. 
4.2 days. 
210 days. 
70 days. 
1 The vacuum frequency recorded here represents the percent of time that a pressure of less than X pound 
per square inch could be expected to be recorded in a series of lowest pressures obtained from consecutive 15 
minute intervals. 
2 The vacuum expectancy is the expected length of time (in days) required for a pressure of less than 1 
pound per square inch to be recorded in a series of lowest pressures obtained from consecutive 16 minute 
intervals. 
From the results of this survey it is evident that if building B 
contained the same number of defective plumbing fixtures of the same 
or similar type as did building C, then the hazard presented by these 
fixtures in building B would be very much greater than that pre- 
sented by the same fixtures in building C. In other words, using the 
results of this study as a criterion, the fixtures in building B repre- 
sent an almost constant menace to the purity of the water in the 
building, whereas the fixtures in building C present a negligible 
hazard. The other buildings studied in this survey grade themselves 
between these two extremes. Figure 25.—Building B. Typical pressure chart. 
218645—10 (Face p. 72) CHAPTER V 
SUGGESTED METHOD OF COMPARING RESULTS OF PLUMBING 
INSPECTIONS 
The project described in chapter 111 contributed a large volume 
of information on the conditions of the plumbing fixtures and in- 
stallations in use in the buildings covered. There is a lack, however, 
of a suitable method for comparing the hazard presented by the 
plumbing of one building with that of others. This chapter has been 
devoted, therefore, to the development of a tentative method of rating 
the plumbing in buildings in order that a more accurate and com- 
prehensible comparison may be made between individual buildings or 
between buildings and an arbitrary standard. 
The method of rating suggested here should not be construed as 
furnishing a superlatively exact figure for each building considered, 
for. like most rating schemes, the basic figures depend upon the judg- 
ment of the inspecting official. Further, this rating device must be 
tentative until frequent application either justifies it or indicates 
valuable and useful modifications. 
As already stated, the accuracy of this proposed rating system 
is very closely related to the judgment of the one making the in- 
spection. Therefore, in its application, comparisons should be made 
between results secured by individuals within the same organization. 
Only in this way can it be expected that errors of or variations in 
judgment will be at a minimum. If the results secured by working 
groups in two or more different cities are to be compared, the pro- 
cedures of inspection used in those locations should first be standard- 
ized. The results from the use of this plan in a group all of whom 
have been trained together should be in close agreement. Despite 
these shortcomings, the rating method suggested herewith merits 
consideration as it furnishes a useful means of comparing the results 
of several plumbing inspections, an aid which up to now has not 
been available. 
Building hazard rating.—Each building inspected shall be given a 
numerical rating indicative of the hazard presented by all of the 
plumbing fixtures and installations in place and in use in the building. 
This rating may be known as the building hazard rating. Any in- 
TENTATIVE PLUMBING INSPECTION RATING SYSTEM 
218645—40 6 74 
crease in the numerical value of the rating shows an increase in the 
hazard presented. 
The building hazard rating may be determined by the following 
empirical formula: 
B=KFDP 
where: 
i?=Building hazard rating 
jBT=l,OOO 
Fixture hazard rating 
system hazard rating 
P=Pressure hazard rating 
Each of the above three complementary ratings (F, D, and P) 
will depend upon the investigations and conclusions of the organi- 
zation making the inspections and each will have a definite upper 
limit. Any rating above any upper limit will cause the entire build- 
ing to be classed as unsatisfactory. The limiting standards used 
herein have been established for illustrative purposes only and 
should not be accepted as applicable to all future work. It is recog- 
nized that it will be preferable for each organization conducting 
work of this kind to establish its own limits to conform to a factor 
of safety previously decided upon. This would in no way affect this 
rating scheme except to change the mathematics of the computations. 
The constant K in the above formula is set at a value of 1,000 only 
to add significance to the final product. It is an arbitrary figure and 
has no bearing on the various ratings. 
The -fixture hazard rating (F) of a building shall be the average of 
the ratings for each separate fixture and plumbing installation in the 
building and may be expressed empirically as: 
„S(|>/) 
s («) 
where: 
F=Fixture hazard rating. 
n—number of each type of fixture. 
/=individual fixture hazard rating. 
These separate fixture ratings will depend upon the design and the use 
of each fixture or connection. The numerical value of the rating 
given each fixture shall be determined by the inspector making the 
examination in accordance with the following limitations: 
None 0 
Remote 0-5 
Potential 5-10 
Definite 10-20 
Serious 20-50 
The existence and use of the fixture presents a menace so 
to require correction upon detection above 50 
Degree of hazard Fixture rating if) 75 
In connection with the fixture ratings, the existence in a building 
of one or more separate fixtures or connections having a rating of 
more than 50 shall be considered sufficient cause to classify the con- 
dition of the plumbing in the building as unsatisfactory. Also, a 
fixture hazard rating (F) for the entire building in excess of 10 shall 
be sufficient cause to classify the building as unsatisfactory as to 
plumbing. 
In arriving at the numerical ratings to be given to each separate 
fixture, a siphon jet water closet supplied through an unstable flush 
valve (a flush valve, the opening of which is facilitated by the occur- 
rence of a vacuum in the supply line to the valve) unprotected by 
either check valve or siphon breaker would be given a hazard rating 
(/) of 10. All other fixtures are graded accordingly. 
The distribution system hazard rating {D) defines in figures the 
condition of the water piping system of a building, the method of 
operation and maintenance of the distribution system, the type of 
system in use and the adequacy of its design. This rating should 
be made by the official in charge of the investigations and should 
be based upon his knowledge of the conditions in the building and his 
observations of the method of operation and maintenance of the dis- 
tribution system. The numerical value for (D) may vary between 1 
and 5. A value of 1 for a building indicates that the distribution 
system is free from any defects either in design, condition, mainte- 
nance, or operation, while a value of 5 shows a distribution system so 
poorly designed, maintained or operated as to warrant its classifica- 
tion as unsatisfactory. 
The small numerical range allowed an inspector in rating the dis- 
tributing system has the advantage of simplifying the task and, also, 
of reducing the effects of any errors in judgment on his part in 
grading the system. 
The pressure hazard rating [P) of a building shall express the 
maximum frequency with which a vacuum may occur in any part of 
the building; such frequency being determined by the method ex- 
plained in chapter IV or one similar to it. A value for (P) of 0.001 
has been set up as the maximum vacuum frequency permitted with- 
out causing the plumbing of the entire building to be classed as 
unsafe. This figure is obviously an arbitrary one and it should be 
established only after careful consideration of all related factors by 
each organization undertaking surveys. 
It has been shown by other investigators in this field that the 
existence of plumbing fixtures and connections in a building of only 
approved design will preclude any possibility of contamination being 
transmitted or spread through the plumbing system. In such a case, 
the application of this method of rating would indicate a fixture 
hazard rating (F) of zero. This rating when multiplied by the dis- 76 
tribution system hazard rating (/>) and the pressure hazard rating 
(P) will give a building hazard rating (B) of zero which would indi- 
cate that the plumbing system of the building was entirely free of any 
health hazards. 
In the distribution system of a building, inadequate design and 
poor physical condition, operation, and maintenance all influence the 
degree of hazard attached to any defective plumbing fixtures found 
in a building. The improper location of pipes and plumbing equip- 
ment, i. e., the location of soil or waste lines above open drinking- 
water tanks, often present a considerable amount of danger. The 
effect of any defects in the distribution system is accounted for in 
the rating given it by the inspector. In the possible case of a build- 
ing containing a distribution system of such design, condition, opera- 
tion, tjrpe, and maintenance that it presents no hazard in itself and 
its influence due to its relation to fixtures is negligible, the distri- 
bution system hazard factor (D) would be 1. This, when multiplied 
by the other two ratings affecting the building hazard rating, would 
have no effect on the final product. 
The third separate rating, the pressure hazard rating (P)< is based 
on the vacuum frequency in the building. Since the majority of 
defective fixtures require the occurrence of a vacuum in the supply 
line to the fixture before back-siphonage can take place, the fre- 
quency with which that occurs modifies the hazard presented by the 
fixture. If the vacuum frequency is low, the hazard is low and 
vice versa. An apparent objection to the pressure-hazard rating 
exists in the case of a building in which the vacuum frequency is 
extremely low and in which there are one or more fixtures through 
which contamination may be spread without the necessity for a vac- 
uum to occur. This difficulty can be surmounted only by giving it 
special consideration. However, the small number of these fixtures 
as compared with the number of those which do need a vacuum 
to make them hazardous does not warrant any deviation from the 
formula devised. 
APPLICATION OF SYSTEM 
To illustrate how the plumbing inspection rating method just de- 
scribed may be applied to various buildings, five of those used in 
the vacuum study explained in chapter IV have been rated and de- 
tailed examples of the rating procedure have been given for build- 
ings B and C. 77 
Examples of calculation: Building B. Total number of fixtures 
inspected, 216. 
Type of fixture in) if) inf) 
Lavatories 47 0 0 
Lavatoi'ies 13 1 13 
Flushometer closets 12 10 120 
High tank closets 73 3 219 
Sinks 7 0 0 
Sinks 11 1 
Showers 9 0 0 
Urinals . 29 3 87 
Slop sinks 10 0 0 
Slop sinks 13 3 
Drinking fountains 5 5 25 
Tanks » 3 13 
Suction ejectors 1 10 10 
Cooling jackets 1 10 10 
Water line in sump 1 10 10 
Hot water line drain 15 5 
Wells 2 20 40 
S(n)2l6 2inf) 546 
/ \ -r-,. . , , r 2(n/) 546 
[a) fixture hazard rating, t = Y{n)~2lQ=^’^ 
Condition of distribution system—poor. 
Operation and maintenance—very unsatisfactory. 
Adequacy of distribution system—fair. 
Type of distribution system—upfeed. 
(b) Distribution system hazard rating. D = 0.0. 
(o) Pressure hazard rating. P (see results of vacuum study) = 
0.25. 
(d) Building hazard rating. B=KFDP= 1,000X2.5X5.0X0.25 = 
3,100. 
Building C. Total number of fixtures inspected, 712. 
Lavatories 268 1 268 
Flushometer closets 273 10 2,730 
Sinks 4 0 0 
Showers . 27 0 0 
Urinals 77 10 770 
Slop sinks 55 0 0 
Drinking fountains 2 3 6 
Developing tanks 5 5 25 
Photostat machine 15 5 
2(a) 712 2inf) 3,804 78 
(a) Fixture hazard rating. F= = 5.3 
Condition of distribution system—good 
Operation and maintenance—good 
Adequacy of distribution system—good 
Type of distribution system—downfeed 
(b) Distribution system hazard rating. D—l.o 
(c) Pressure hazard rating. P (see results of vacuum study) 
= 0.0000 + 
(cI) Building hazard rating. B = KFDP = 1.000 X 5.3 X 1.0 
X 0.0000+=0.0000 + 
Summarizing the ratings of the five buildings we have: 
Table XV.—Ratings of 5 New York office buildings 
Building 
F 
D 
P 
B 
B 
2.6 
5.0 
0. 25 
3100. 
C 
5.3 
1.0 
.0000+ 
.0024 
0.0000+ 
8.6 
D 
1.8 
2.0 
E 
2. 7 
3.0 
.000051 
.41 
F 
3.3 
1.0 
.00015 
.50 
Discussion of application.—Upon examination of table XV, it is 
apparent that the hazard presented by the plumbing in building B 
is very much greater than that presented by any other building. An 
examination of the three component parts which make up the build- 
ing rating (B) shows that the hazard presented by the fixtures (F) 
is less than the average for the five buildings. On the other hand, 
the distribution system hazard rating (D) and the pressure hazard 
rating (P) are both excessive. In contrast, the fixtures in building 
C. in themselves, present over twice the hazard as those in building B 
but the hazard surrounding the entire plumbing installation in build- 
ing Cis almost negligible. The reason for this is the extremely low 
vacuum frequency. 
Another comparison of interest is supplied by table XVI where 
the five buildings have been arranged according to age. 
Table XVl.—Ratings of 5 New York office buildings by age of building 
Age of building in years 
Building 
F 
D 
P 
B 
72 . 
B 
2.6 
5. 0 
0. 25 
3100. 
60.. 
D 
E 
1.8 
2. 0 
.0024 
8 6 
51 
2.7 
3.0 
.000051 
41 
4 
c 
5.3 
1.0 
.0000+ 
.00015 
.0000+ 
.50 
1 
F 
3.3 
1.0 79 
Here it becomes evident that in the newest buildings the fixture 
hazard rating is appreciably higher than that for the older buildings. 
In other words, modern plumbing fixtures present more danger to the 
public health, in themselves, than do fixtures of a less recent design. 
On the other hand, the design and adequacy of operation and main- 
tenance of the distribution system have been materially improved. 
This latter factor may also be the cause for the existence of a lower 
vacuum frequency in modern buildings. In any event, the com- 
bined effect of the three separate ratings is such as to indicate an 
increase in the safety of the plumbing in the newer buildings. 
It may be contended that with the passage of several years, the 
distribution systems of the new buildings of today will present as 
great a hazard as those of the older buildings do at the present 
time. If such were the case, the new buildings of today would, in 
perhaps fifty years time, be a source of greater danger to the public 
health than the older buildings are now. It is believed, however, 
that the increasing knowledge of the principles of distribution sys- 
tem design and the factors causing systematic deterioration of those 
systems together with the very evident tendency to a closer control 
of plumbing systems to protect public health will preclude any 
appreciable increase in the hazard presented by the distribution 
systems in use today. 
Application of rating method to corrective measures.—As a result 
of the publicity attending the results of the studies of the several 
investigators in plumbing and its relation to water supply quality 
and public health, a number of cities and states have enacted legis- 
lation designed to prohibit the future installation of defective 
plumbing fixtures. The value of such legislation in effecting the cor- 
rection of certain types of fixtures is, up until the present time, 
unknown. The rating method explained in the first part of this 
chapter will, it is hoped, furnish a yardstick by which the relative 
value of correcting the various types of defects may be estimated 
and compared. To illustrate how this method may be used in esti- 
mating the value of certain corrective measures, the following 
examples are given. 
It is assumed that it is required to change all flush-valve-supplied 
toilets in buildings so that complete protection against back-siphonage 
is provided. The question then is, “what effect will such a change 
have upon the hazard rating of any of the buildings studied?” 
Using building E for an example we find that it has the following 
ratings: 
5 = 0.41 
5=2.7 
D = 3.0 
P= .000051 80 
This building contains 27 water closets of the flush-valve type. 
Before change, each of these closets would have a rating of 10 and 
(nf) would be 270. If complete protection is provided the (nf) for 
the 27 water closets would be zero instead of 270. Deducting 270 
from the 2 (nf) of the building, 412, gives a new 2 (nf) of 142, 
This divided by the building’s 2 (n), 150, gives a new Fof 0.95. 
Substituting in the formula for B: 
5 = 1,000 (0.95) (3.0) (.000051) =0.15 
This represents a reduction in the hazard rating or an increase in 
the safety of the plumbing of the building of: 
0.41-0.15 
041 X 100=63% 
Therefore, the initiation of a measure requiring all water closets 
equipped with flush valves to be altered so as to furnish complete 
protection against back-siphonage, would cause the hazard repre- 
sented by the plumbing in building E to be reduced 63 percent. 
Another application of the rating method to corrective measures 
is in determining the most economical and suitable method of de- 
creasing the hazard connected with the fixtures and installations in 
the building. For instance, from an examination of the ratings for 
building B it is evident from the fixture hazard rating, F. that the 
fixtures alone are not the cause of the high building rating. On the 
other hand, the high distribution system hazard rating, Z>, indicates 
that attention should be directed to a consideration of its adequacy 
and operation. 
The rating method is useful also' in determining the priority of 
corrective measures for the buildings covered. Fixing a building 
hazard rating limit which wdll serve to divide the inspected buildings 
into two groups; one, including those buildings which can be classed 
temporarily as satisfactory and the other, those which require correc- 
tive measures at once, should expedite the initiation and application 
of such measures. Such a limit will, in fact, define the margin of 
safety required for the plumbing installation in use and newly in- 
stalled in buildings within the jurisdiction of the inspecting agency. 
For the five buildings rated in this discussion, a building hazard 
rating of 1.0 might be considered as the limit that is not to be 
exceeded if the buildings are to be temporarily classed as satisfactory. 
An examination of the ratings of the five buildings discloses that 
building B with a (B) of 3,100 and building D with a (B) of 8.6 
would both be classed as unsatisfactory and in need of correction. CHAPTER VI 
CORRECTIVE MEASURES 
The elimination of hazard-producing plumbing fixtures and appli- 
ances from future buildings will depend upon the availability of 
equipment of such design as to conform to rigid sanitary standards, 
adequate supervision of their installation to avoid mistakes and 
control of their employment to preclude misuse. The design of 
over-the-rim fixtures, so as to provide an air gap between the end of 
the inlet spout and the highest possible water level in the fixture of 
such dimensions as to make*impossible the backflow of contaminated 
liquid or material under any condition of vacuum, has been studied 
by investigators in this field. Formulas for the size of air gap re- 
quired for this type of fixture have been developed. Dawson gives 
for the minimum allowable air gap for over-the-rim fixtures, the 
following: G:=<2D for circular openings and G=2Vi^JA for other type 
openings, where G is the air gap in inches, D is the diameter of the 
inlet in inches and A is the minimum area of the inlet in square 
inches {139). This formula is convenient and provides for a factor of 
safety. Hunter et al. as a result of their experiments gives the fol- 
lowing: Y=2.45 d{1~0.26(1 0.28 d) where x is the required air 
gap in inches, d the internal diameter, and D the external diameter 
of the spout in inches. This formula holds true if local variations 
in atmospheric conditions are neglected. Hunter also recommends 
the reduction of the above formula to a? = 1.8 c?, for simplifying its 
application {191). Both of the investigators mentioned above have 
produced formula for the minimum air gap required to furnish full 
protection to over-the-rim fixtures against back siphonage which 
are essentially the same. Dawson’s formula includes a larger factor 
of safety and is probably simpler to apply. Designing and installing 
fixtures of over-the-rim type in accordance with either of the above 
formula will preclude any possibility of back siphonage taking place 
through the fixture. That fixtures of this type are available is shown 
by the fact that the formula G—2D was used in the plumbing survey 
in New York and Detroit as a basis upon which the over-the-rim type 
fixtures were approved or disapproved, and of 6,679 lavatories 
inspected in New York. 1.114 were found to be satisfactory. 82 
In addition to improving the design of certain plumbing fixtures, 
adequate measures for the control and regulation of plumbing systems 
are required in order to safeguard against the installation and use 
of fixtures and connections which may create hazards. These can be 
had through the development and adoption of adequate plumbing 
codes which should provide for the regulation of the various persons 
engaged in building plumbing systems and of the material to be used, 
the latter to include sizes of pipes and types of connections allowed 
and prohibited. Only qualified workmen should be permitted to in- 
stall or alter plumbing fixtures and then only after securing a permit 
from a duly constituted authority to do so. An inspection of the 
completed work should assist materially in reducing errors in work. 
The submission of plans of new work for review would permit the dis- 
covery of possible dangerous arrangements. The inclusion in plumb- 
ing codes of definite standards for the design and installation of 
plumbing fixtures should result in the establishment of a standardized 
and safe system of plumbing. 
To correct existing defects, a survey organization for the discovery 
and location of them is desirable. Such an organization working 
with a method similar to that suggested in chapter V can locate and 
note the existence of plumbing defects and health hazards requir- 
ing immediate correction. By setting up limits defining the dividing 
line between safe and unsafe installations such an organization would 
be able to find those buildings and plumbing systems that are unsat- 
isfactory and a menace to health. Requiring all existing instal- 
lations to meet certain definite standards of safety would result 
in a lessening of the possibility of the spread of contamination 
through such fixtures and connections, and periodic reinspections by 
a survey organization would reduce the possibility of the conversion 
of a safe fixture to a potential hazard through alterations in the 
design of the fixture to meet the user’s need. 
Another method for obtaining the correction and elimination of 
defective and hazardous fixtures is through the development of an 
educational program for the dissemination of information on what 
constitutes a safe fixture and on the hazards of back-siphonage. 
Models, plumbing exhibits, motion pictures, and published articles 
are all examples of how information regarding plumbing hazards 
and their possible effect on water-supply quality may be spread. 
Photographs of plumbing-code violations, poorly designed plumb- 
ing fixtures, and health hazards resulting from alterations in fixtures 
due to the nature of their uses are often helpful for educational pur- 
poses. In the course of the completion of the New York survey 
summarized in chapter 111 a number of photographs were taken 
of existing defects. These photographs illustrate a number of de- Figure 26.—lavatory With Drain out of Window. FIGURE 27.—HOT WATER TANK DRAIN LINE figure 28.—Direct drain and Overflow connection. Figure 29.—Potato Peeler Interconnection. Figure 30.—Submerged Hose in sink. Figure 31 .—Water-Soil line Interconnection 83 
ficiencies ranging from minor code violations to serious health 
hazards. Figures 26 to 28 illustrate the results of unsupervised 
plumbing installations. In Figure 26 the photograph shows a lava- 
tory installed in a most unworkmanlike manner. The drain from 
the fixture instead of being connected to a waste stack and discharg- 
ing into the house drainage system has been run out of a second- 
story window and discharges upon the ground next to the building. 
Figure 27 shows another unsatisfactory installation. In this case 
the drain from the bottom of the hot-water tank (end just visible 
at the left side of the picture), runs along the floor as shown and then 
turns up and connects into the drain line leading to the top of the 
trap. With the water-supply line shut off, any attempt to empty the 
tank through the drain line could easily result in sewage flowing 
into the tank rather than the water draining out, especially under 
conditions of stoppage or overloading in the soil stack. Another 
possibility of contamination exists as a result of this connection. 
The water-supply line to the tank enters at the bottom so that with 
a vacuum in the line the water would be drawn out of the tank 
together with any contaminated water or sewage that may be 
sucked out of the drain line through an open or leaky valve. 
The main deficiency in a number of installations is the presence 
of a direct path through which contamination may pass from the 
waste or sewerage system into the water supply system. An instance 
of this defect is illustrated in Figure 28. Here there is shown three 
defective and potentially dangerous installations. The drain from 
four filters and the drain and overflow from the suction tank on the 
domestic supply system are all connected directly into the house 
drain. That any or all of these lines may be subject to a definite 
back pressure may be realized by noting the existence of the soil stack 
rising diagonally across the left corner of the photograph. The oc- 
currence of a stoppage in the house drain at a point beyond these 
connections may permit sewage or waste water to back up in the soil 
stack and exert an increasing pressure on the drain valves and upon 
the check valve located in the overflow pipe. The existence of a 
direct connection between the house drain and the two drains and 
overflow previously mentioned will almost preclude the possibility of 
observing whether the valves are tight and not leaking. With an 
indirect connection to the house drain, the leaking of any of the valves 
would be immediately apparent. 
All of the foregoing illustrated defects are the result of inadequate 
control over the installation of plumbing fixtures and connections. 
The requirement that plumbing fixtures be installed by qualified 
workmen fully cognizant of the hazards of faulty installations will 
preclude the occurrence of such eventualities. 84 
The alteration of a plumbing fixture during its use is responsible 
for the existence of several common defects. In figure 29 a water line 
is shown connected into the waste line from a potato peeler. The 
purpose of this connection was to assist in flushing the potato peelings 
into the sewer. Should a vacuum occur on this water line together 
with an open or leaking control valve it would be possible for con- 
taminated material to be drawn from the waste line back into the 
water supply. 
Figure 30 illustrates another similar installation. In this case, a 
rubber hose has been connected to the cold water faucet of a general 
utility sink. The purpose of it was to assist the porter in cleaning 
cuspidors. The dangerous feature of this installation is the fact 
that when not in use, the end of the hose is allowed to rest on the 
bottom of the sink and occasionally may be submerged in the sink 
contents. Such a condition is illustrated in the picture. Should a 
vacuum occur on the water line under these conditions and should 
the inlet valve be opened or leaking it would be possible for a portion 
of the contents of the sink to be drawn into the water line. 
Another illustration of a man-made interconnection is shown in 
figure 31. In this case, a 2-inch water line has been connected into a 
6-inch soil line. The soil line discharges into a tidal bay below the 
high-water level. As a result it is occasionally subject to stoppages. 
The purpose of the water line, therefore, was to furnish a stream of 
water to the soil pipe to flush out any deposited material. If a vacu- 
um were to occur on the water line or if the pressure in the soil line 
were to become greater than the water pressure and the valve was 
open or leaking, contamination of the water supply would be apt to 
result. 
All of the preceding illustrations indicate the necessity for a com- 
plete inspection of the plumbing of both existing buildings and 
buildings constructed in the future. The need for occasional rein- 
spections of existing buildings is manifested by the illustrations shown 
in figures 29 to 31. In spite of the fact that plumbing fixtures may 
be of approved design when first installed, the nature of their use 
may result in changes and alterations in them such that the fixture 
may be converted into a public health hazard. Periodic reinspec- 
tions plus a comprehensive educational program may be expected to 
do much toward the reduction in the number of such unethical 
alterations. 
CONCLUSIONS 
Millions of dollars have been spent for the purpose of locating, 
developing, and supplying pure water to the public, and noteworthy 
advances have been made in the processes for the treatment and puri- 
fication of water and for its ultimate distribution to the consumer. 85 
The result has been a marked decrease in the number of cases of water- 
borne diseases. Spontaneous and sporadic outbreaks, however, of both 
mild and severe cases of intestinal disturbances have shown that the 
safeguarding of the water supply has been inadequate in certain 
respects. Connections have been made and fixtures and appliances 
installed and used that present a possible source of contamination of 
the water supply. The outbreak of amebiasis in Chicago in 1933 
emphasized the dangers resulting from the installation and use of 
faultily designed plumbing and aroused much interest in this field 
resulting in renewed investigatory activity. Many phases of the 
subject have been covered including survey work, research on proper 
fixture design, initiation of corrective measures, and investigations into 
the availability of safe, sanitary plumbing fixtures. The direct result 
of all these studies has been an indication of the need for further 
inquiry into plumbing hazards as they exist in buildings in an effort 
to rationalize the hazard attributed to their installation and use. The 
lack of adequate means by which the hazard presented by the installa- 
tion of defective plumbing fixtures may be determined has necessi- 
tated the development of a system whereby the results for various 
buildings may be evaluated and compared. This method of approach 
has been to reduce the findings of an inspection party to a numerical 
rating that is indicative of the amount of danger resulting from the 
installation and use of the defective fixtures and connections in each 
building. This has made possible a better conception of the dangers 
of various plumbing systems and connections and a more accurate 
correlation of the factors influencing the amount of hazard presented. 
Justification for extended plumbing inspection is vouchsafed by 
the results obtained by the New York and Detroit survey of the 
Works Progress Administration and the United States Public Health 
Service. The location and correction of several separate installa- 
tions having a very high hazard rating has indicated the existence 
of such dangers which, even though few in number, contribute con- 
siderably to the health hazard present in the plumbing systems in 
use today. The discovery and correction of these obscure but highly 
dangerous fixtures or connections may be assured only by a compre- 
hensive investigation of all the plumbing systems installed and in 
use at the present time. Elimination and prevention of the instal- 
lations of this type of fixture and connection in the future may be 
assured through a rigid control of the plumbing being installed in 
a building and through the education of plumbers, architects, engin- 
eers, and the public at large in the fundamentals of safe plumbing. BIBLIOGRAPHY 
Note.—Bibliography is current as of June 1, 1939. 
1. Life is a priceless gift. 
The Sanitary Institute, St. Louis, Mo. Pamphlet, 3 pp. 
2. The lesson of the Michigan plumbing tragedy. 
Plumbing and Heating Business, 1: No. 8: 11 (Apr. 1939). 
3. Where to look for cross-connections or backsiphonage. 
The Pennsylvania Master Plumber, 1: No. 3; 18 (Dec. 1938). 
4. Pollution dangers within buildings and their control. 
Water Works Engineering, 91: 1502 (Nov. 9, 1938). 
5. The issue of the hour. 
Plumbing and Heating Business, 1: No. 1: 15 (Sept. 1938) 
6. Address on research. 
National Association of Master Plumbers, June 6-9, 1938. Pamphlet. 9 pp. 
7. Outstanding features of New York City’s new plumbing code. 
Domestic Engineering, 150: 69 (Mar. 1938). 
8. Cross connections. 
Domestic Engineering, 149: 87 (May 1937). 
9. Texas exhibit. (Houston, Tex.). 
Domestic Engineering, 149: 148 (May 1937) 
10. Lessons for sanitary engineers provided by dysentery epidemic. 
Municipal Sanitation, 8: 175 (Mar. 1937). 
11. Back siphonage research undertaken by the industry. 
Architectural Record, 81: 43 (Jan. 1937). 
12. Chicago activities. 
Domestic Engineering, 148: No. 4: 130 (Oct. 1936). 
13. Water closets, flushing devices and back siphonage. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
101: No. 4: 66 (Oct. 1936). 
14. Survey bares plumbing faults. 
The Ladle, 12: 13 (Sept. 1936). 
15. Privies and bad plumbing doomed in Louisville health crusade. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
16. Texas exhibit. (San Antonio, Tex.) 
101: No. 3: 38 (Sept. 1936). 
17. Maryland-Delaware conference reviews sewage treatment problems. 
Municipal Sanitation, 7: 210 (June 1936). 
Domestic Engineering, 148: No. 2: 123 (Aug. 1936). 
18. Hotel plumbing revamped for water works convention. 
Engineering News-Record, 116: No. 25: 879 (June 18, 1936). 
19. St. Louis research laboratory spreads the gospel of sanitation. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
20. What’s being done in Wisconsin. 
99: No. 6: 74 (Dec. 1935). 
Domestic Engineering, 146: No. 5; 61 (Nov. 1935). 87 
21. Sanitary engineers discuss cross-connections. 
Municipal Sanitation, 6 : 296 (Oct. 1935). 
22. Reasons for plumbing codes. 
Domestic Engineering, 146: No. 3: 77 (Sept. 1935). 
23. Importance of plumbing is recognized by Congress. 
24. Closet bowl back siphonage tests staged in Cincinnati. 
Domestic Engineering, 145: 70 (June 1935). 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
98: No. 3: 42 (Mar. 1935). 
25. The problem of back-syphonage. 
Skyscraper Management, 20: No. 3: 10 (Mar. 1935) 
26. Back-siphonage. 
Illinois Master Plumber, 20: 14 (Jan. 1935). 
27. The Chicago breaker tests. 
Domestic Engineering, 145: 40 (Jan. 1935). 
28. Cross connections present danger of pollution. 
Municipal Sanitation, 5: 348 and 384 (Oct. and Nov. 1934). 
29. Cross-connection regulation. 
Water Works Engineering, 87: No. 26: 1156 (Oct. 17, 1934). 
30. Stop cross connections with police help. 
Domestic Engineering, 142: 51 (June 1934). 
31. Dysentery epidemic detailed before waterworks body. 
Engineering News-Record, 112: No. 24; 779 (June 14, 1934). 
32. Louisiana-Mississippi association approves back-siphonage guard. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
96: No. 6: 53 (June 1934). 
33. Murphy to urge N. A. M. P. action on “amebiasis” at convention. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 96: No. 5: 17 (May 1934). 
34. Plumbing and health. (Editorial). 
Hygeia, 12: 198 (Mar. 1934). 
35. Chicago dealers war on handyman plumbing. 
Illinois Master Plumber, 19: 9 (Mar. 1934). 
36. Amebiasis outbreak due to defective plumbing in hotels. 
Municipal Sanitation. 5: 98 (Mar. 1934). 
37. Chicago will inspect old buildings for faulty plumbing. 
Illinois Master Plumber, 19: 10 (Feb. 1934). 
38. Trace amebic dysentery to bad plumbing. 
Illinois Master Plumber, 19: 7 (Feb. 1934). 
39. N. A. M. P. files plumbing health brief in support of its code. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
95: No. 6: 42 (Dec. 1933). 
40. Cross connection preventive built into hospital plumbing. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 93: No. 6: 35 (Sept. 1932). 
41. See 3,000,000 remodeling jobs in cross connection menace. 
Phunbing and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 92; No. 11: 56 (Mar. 15, 1932). 
42. Constructive program of research and education advanced at A. S. S. E. 
meeting. 
Plumbers and Conti’actors Trade Journal (now Plumbing and Heating 
Journal), 89: 36, (Sept. 1, 1930). 88 
43. Contamination of water systems by consumers’ water uses. 
Engineering News-Record, 105: No. 4: 141 (July 24, 1930). 
44. Pool cross-connection outlawed. 
Municipal Sanitation, 1: 336 (June 1930). 
45. Demonstration of hospital plumbing—cross connections draw attention of 
thousands. 
Plumbers and Contractors Trade Journal (now Plumbing and Heating 
Journal), 87: No. 10: 49 (Nov. 15, 1929). 
46. Sanitary engineers hold 24th annual meeting. 
Domestic Engineering, 128: No. 6: 159 (Sept. 21, 1929). 
47. American Society of Sanitary Engineering holds spirited convention in 
Detroit. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 87: No. 6: 46 (Sept. 15, 1929). 
48. Plumbing, heating, ventilating and public health. 
Domestic Engineering, 118: No. 1; 53 (Jan. 1, 1927) ; and 118: No. 6: 21 
(Feb. 5, 1927). 
49. Typhoid fever and cross-connections in Illinois. 
Engineering News-Record, 94: No. 13: 526 (Mar. 26, 1925). 
50. Water supply cross-connection rules of Ontario Board of Health. 
Engineering News-Record, 87: No. 9; 374 (Sept. 1, 1921). 
AMERICAN PUBLIC HEALTH ASSOCIATION 
51. Basic principles of healthful housing. (Report of Committee on Hygiene of 
Housing. 
American Journal of Public Health. 28: 851 (Mar. 1938). 
52. Plumbing. (Progress report of committee). 
American Public Health Association Yearbook, p. 159 (1936-1937). 
53. Newer aspects of amebic dysentery. (Committee report.) 
American Journal of Public Health, 26: 1023 (Oct. 1936). 
54. Recent developments in plumbing as related to public health. (Committee 
report.) 
American Public Health Association Yearbook, p. 226 (1935-1936). 
55. Manufacturers giving more attention to public health aspects of plumbing 
fixture design. (Progress report of joint committee of American Public 
Health Association and the Conference of State Sanitary Engineers.) 
American Public Health Association Yearbook, p. 80 (1933-1934). 
56. Eliminating health hazards in plumbing. (Progress report of committee.) 
American Public Health Association Yearbook, p. 129 (1930-1931). 
57. Essential features in the design of sanitary drinking fountains. (Report of 
committee on plumbing.) 
American Journal of Public Health, 19; 1223 (Nov. 1929). 
AMERICAN SOCIETY OF SANITARY ENGINEERING 
58. Report of conference on cross-connections, Washington, D. C., Feb. 24-25, 
1932. (Committee report.) 
Proceedings, American Society of Sanitary Engineering, 10:215 (1932). 
59. Cross-connections. 
Proceedings, American Society of Sanitary Engineering, 14:75 and 158 
(1928-1929) and 15:239 (1930-1931). 89 
AMERICAN STERILIZER COMPANY 
60. Relating to the selection, arrangement, and installation of sterilizers. San- 
itary protection of sterilizer connections. 
Catalog, American Sterilizer Company, Section Z, p. 15 (Jan. 1936). 
AMERICAN WATER WORKS ASSOCIATION 
61. Report of Committee on Convention Hotel Sanitation. 
Journal, American Water Works Association, 28:251 (Feb. 1936). 
62. Report of Committee No. 8 on Cross-connections. 
Journal, American Water Works Association, 25:396 (Mar. 1933). 
63. Final report of the Committee on Sanitary Drinking Fountains of the 
American Water Works Association. (lowa Section.) 
Journal, American Water Works Association, 7:33 (1920). 
ANGUS, W. M., AND FRANCIS, CARL 
64. Leaky cross-connections located by alkali test. 
Engineering News-Record, 84: No. 25: 1187 (June 17, 1920). 
ARNOLD, G. E. 
65. Back-siphonage and cross-connections. 
Journal, American Water Works Association, 28; 234 (Feb. 1936). 
BALTIMORE, CITY DEPARTMENT OF HEALTH 
66. Plumbing cross-connection results in acute lead poisoning. 
Baltimore Health News, 13: No. 8: 52 (Aug. 1936). 
67. That Chicago epidemic. 
The Quill, 22:4 (Apr. 1934) 
BAESANTEE, HAKRY 
BAXTER, A. C 
68. The role of the plumber in his local health program. 
Illinois Master Plumber, 23:17 (Apr. 1938). 
BEAM, JAMES R. 
69. Some suggestions on testing water-closet bowls. 
Proceedings, American Society of Sanitary Engineering, p. 168, (1933). 
BENNETT, ALBERT A. 
70. Research work as applied to scientific development and as employed for 
sanitary regulations. 
Western Plumbing and Heating Journal (Los Angeles, Calif.), p. 5 (Dec. 
1933). 
BOOSEY, NORMAN 
71. Plumbing hazards to health. 
The Ladle, 15: 16 (Mar. 1939). 
218645—40 7 90 
72. Cross-connections. 
bkooks, e. a. 
Proceedings, American Society of Sanitary Engineering, p. 47 (1933). 
BUNDESEN, H. N. 
73. What of the future in plumbing? 
Illinois Master Plumber, 21: 2 (Feb. 1936) 
74. Plumbing in relation to infectious diseases. 
American Journal of Tropical Medicine, 15:455 (July 4, 1935). 
75. Dr. Bundesen urges safe plumbing installations. 
Bulletin, National Association of Master Plumbers, 3:4 (May 1935). 
76. Revival of interest in safety of plumbing sweeps over country. 
Bulletin, National Association of Master Plumbers, 3:12 (April 1935). 
77. Health hazards in plumbing. 
78. Why cross-connections are health hazards. 
Domestic Engineering, 145 : 52 (Feb. 1935). 
Modern Hospital, 44: 71 (Apr. 1935). 
79. The Chicago epidemic of amebic dysentery. 
Public Health Reports, 49: 1266 (Oct. 26, 1934). 
80. Prevention of amebic dysentery. 
Bulletin, National Association of Master Plumbers, 2: No. 10; 17, and 
2: No. 11: 13 (Sept, and Oct. 1934). 
81. Amebic dysentery. Its influence on plumbing. 
Illinois Master Plumber, 19; 7 (Mar. 1934). 
82. Amebic dysentery in Chicago. 
American Journal of Digestive Diseases and Nutrition. 1: No. 1: 9 (Mar. 
1934). 
BUNDESEN, H. N., TONNEY, F. 0., AND RAWLINGS, I. D. 
83. The outbreak of amebiasis in Chicago. 
Journal, American Medical Association, 102: No. 5: 367 (Feb. 3, 1934). 
CALNAN, JOHN J 
84. The activities of the National Association of Master Plumbers in connection 
with amebic dysentery. 
Bulletin, National Association of Master Plumbers, 3: No. 5: 8 (May 1935). 
CAMP, THOMAS B. 
85. The hydraulics of water-closet bowls and flushing devices. 
Cooperative research project of the Massachusetts State Association of 
Master Plumbers and the Department of Civil and Sanitary Engineering 
of the Massachusetts Institute of Technology. 126 pp. (May 1936). 
CANTON, E. j. 
86. Cross-connections and their elimination. 
Proceedings, Maryland Water and Sewerage Association, 2nd Annual Con- 
ference, p. 88, 1928. 
87. Plumbing defects, their significance. 
CARPENTER, LEWIS V. 
The Greater City Plumber, 3: No. 1: 14 (Jan. 1937). 91 
CHICAGO, CITY DEPARTMENT OF HEALTH 
88. Drinking fountains. 
Report 1926-1930, Department of Health, City of Chicago, p. 375. 
89. Plumbing cross-connections. 
Report 1926-1930, Department of Health, City of Chicago, p. 376. 
90. Cross-connections with the water-supply system. 
Report 1923-1925, Department of Health, City of Chicago, p. 468. 
CLAFFEY, THOMAS J. 
91. Report of special Committee No. 5 on plumbing fixtures. 
Proceedings, American Society of Sanitai‘y Engineering, 17 : 770 (1933-1935). 
92. Report of research committee on sanitary drinking fountains. 
Proceedings, American Society of Sanitary Engineering, 16 : 203 (1932). 
93. Report of research committee on cross-connections through flush valves. 
Proceedings, American Society of Sanitary Engineering, 16; 206 (1932). 
94. Research upon siphonage through flush valves. 
Proceedings, American Society of Sanitary Engineering, 15: 271 (1930-1931). 
95. Tests on water closets and flush valves. 
Proceedings, American Society of Sanitary Engineering, 14: 71 (1928-1929). 
CLEVEEDON, W. S. L. 
96. Cofunctions of traps and vents in plumbing. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
96: No. 2: 28 and 96: No. 3: 31 (Feb. and Mar. 1934). 
97. New plumbing data revealed in “lab” tests. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and Heat- 
ing Journal), 93: No. 2: 35 (May 1932). 
COLEMAN, C. J. 
98. Adoption of sanitary engineering principles in hospital fixtures and 
Proceedings, American Society of Sanitary Engineering, 16: 153 (1932). 
equipment. 
99. Requirements for drainage and toilet systems. 
Connecticut Health Bulletin, 52: 14 (Jan. 1938). 
CONNECTICUT DEPARTMENT OF HEALTH 
100. Watertmry acts to prevent pollution of house water piping. 
Connecticut Health Bulletin, 44: 38 (Feb. 1930). 
CONNOLLY, JOEL I, 
101. Plumbing in low cost housing. 
American Journal of Public Health, 28: 954 (Aug. 1938), 
102. Good plumbing plus vigilance equals health. 
The Ladle, 14: 9 (Aug. 1938). 
103. Plumbing as an industrial hygiene problem. 
Illinois Master Plumber, 23: 13 (July 1938) 
104. Cross-connection crimes. 
Engineering News-Recoi'd, 120: No. 16: 575 (Apr. 21, 1938) 92 
105. Regulation of plumbing as a public health measure. 
Transactions, Southern Branch of the American Public Health Association, 
p. 63 (1937). 
106. Serving disease to consumers via pipes and fixtures. 
Water Works Engineering, 89: 631 (May 27, 1936). 
107. Safeguarding the sterile water supply. 
Modern Hospital, 45: No. 1: 61 (July 1935). 
108. Plumbing and' health in Chicago. 
Illinois Master Plumber, 18: 17 (June 1933) 
109. The importance of plumbing to public health. 
Proceedings, American Society of Sanitary Engineering, p. 176 (1933). 
110. Private cross-connections. 
Proceedings, 13th Annual Texas Water Works Short School, p. 33 (1931). 
111. Sanitary aspects of drinking fountains. 
Proceedings, American Society of Sanitary Engineering, 15: 278 (1930- 
1931). 
112. Private cross-connections and similar menaces to public water supply 
quality. 
Journal, American Water Works Association, 23: 495 (Apr. 1931). 
113. Danger of private cross-connections. 
Canadian Engineer, 59: No. 20: 627 (Nov. 11, 1930). 
114. Private cross-connections and similar menaces to the quality of water. 
Water Works and Sewerage, 77: 309 (Sept. 1930). 
115. Faulty private cross-connections prove perpetual menace to health. 
Water Works Engineering, 83: 1081 (July 16, 1930). 
116. The function of the city sanitary engineer. 
Municipal Sanitation, 1: 22 (Jan. 1930). 
117. Address on cross-connections. 
Proceedings, American Society of Sanitary Engineering, 14; 102 (1928- 
1929). 
118. Progress in elimination of cross-connections with especial reference to hos- 
pitals. 
Proceedings, American Society of Sanitary Engineering, 12: 234 (1928- 
1929). 
119. Now we will do some plumbing. 
Domestic Engineering, 124: No. 10: 28 (Sept. 8, 1928). 
120. Submerged inlet fixtures. 
Plumbers and Contractors Trade Journal (now Plumbing and Heating 
Journal), 85: No. 1: 70 (July 1, 1928). 
121. Cross connections. 
Domestic Engineering, 123: No. 12: 18 (June 23, 1928). 
122. Modern plumbing—the price of public health. 
Domestic Engineering, 121; No. 10: 18 (Dec. 3, 1927). 
CORNELIUS, LOUIS A. 
123. They die from neglect. 
Pamphlet, 56 pp. (1936) 
COWLES, m. w. 
124. What interest has a water purveyor in interior plumbing systems in rela- 
tion to cross-connections. 
Journal, New England Water Works Association, 51: 261 (Sept. 1937). 93 
CRAIG, C. F. 
125. The epidemiology of amebiasis. 
Journal, American Medical Association, 103: No. 14: 1061. (Oct. 6, 1934). 
126. Coping with the problems of plumbing and heating in today’s hospitals. 
Crane Company Hospital Service Catalog No. 620-c, 7 pp. (1931). 
CKANE COMPANY 
CKONKRIGHT, A. B. 
127. Disapproved plumbing fixtures—how hazardous? 
Water Works and Sewerage, 85: 801 (Aug. 1938). 
128. Disapproved plumbing . . . how dangerous is it? 
Plumbing and Heating Journal, 104: No. 6: 24 (June 1938). 
129. When is plumbing a health hazard? 
The Ladle, 14: 13 (June 1938). 
ORONKEI6HT, A. 8., AND MHXER, ARTHUR P. 
130. Added security for the public. 
Water Works Engineering, 91: 492 (Apr. 13, 1938). 
131. The effect of certain small filters on plate counts of water passing through 
them. 
Public Health Reports, 53: 505 (Apr. 1, 1938). 
CROTTT, JOSEPH J. 
132. Reinspection of plumbing prevents diseases. 
Domestic Engineering, 144: No. 5: 137 (Nov, 1934). 
133. Periodical reinspection of plumbing: a factor in disease prevention. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
97: No. 4: 46 (Oct. 1934). 
134. More business—public health protection possible if contractors and associ- 
ations work to impress law-makers with benefits of reinspection. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and Heat- 
ing Journal), 92: No. 1: 34 (Oct. 15, 1931). 
DASHIEL, W. N., AND WHEDBEE, EDGAR 
135. Cross-connection elimination war in Texas cities. 
Engineering News-Record, 104: No. 11: 444 (Mar. 13, 1930) 
DAWSON, F. M. 
136. New developments and trends in -water treatment. 
Water Works Engineering, 89 : 683 (May 27, 1936). 
137. Report on tests of flushometer valves. 
Bulletin, Chicago Hospital Association, p. 3 (Sept. 1930). 
DAWSON, F. M., AND KALINSKE, A. A. 
138. Venting of the plumbing-drainage system. 
Plumbing and Heating Business, 1: No. 6: 14 (Feb. 1939). 
139. Report on plumbing cross-connections and back-siphonage research. 
National Association of Master Plumbers Technical Bulletin No. 1, 79 pp. 
(1938). 94 
140. Control of water piping from main to consumer. 
Journal, American Water Works Association, 30: 464 (Mar. 1938). 
141. Cross-connections in air-conditioning equipment. 
Journal, American Water Works Association, 29: 1673 (Nov. 1937). 
142. Vacuum breaker development for back-sipbonage prevention. 
Journal, American Water Works Association, 29; 307 (Mar. 1937). 
DAWSON, F. M., KING, F. 8., AND KALINSKE, A. A. 
143. How to build a cross-connection and back-sipbonage exhibit. 
Domestic Engineering, 147: 56 (Feb. 1936). 
DAY, LOUIS J., AND STEDMAN, C. W. 
144. Water supply connection—a treatise on swimming-pool design. 
Josam Manufacturing Company, Cleveland, Ohio, A. I. A. File No. 35-f-2, 
33 pp. 
DEMPSTEE, ANDREW T. 
145. Detroit’s plumbing 70% siphonable. 
The Ladle, 13: 13 (July 1937). 
DERBY, RAY L. 
146. Cross-connections between water and sewage systems. 
Journal, California Sewage Works Association, 5: No. 1: 127 (1932-1933). 
DIETEE, LOUIS V. 
147. The relative sanitary value of different types of drinking fountains, Part 
I—the results of tests of vertical-nozzle types; Part ll—how the foun- 
tains are used and the results of tests of sloping stream types. 
American City, 21: 452 and 549 (Nov. and Dec. 1919). 
DOUGLAS, A. M. 
148. Plumbing installations that safeguard health. 
Proceedings, Eleventh Annual Conference, Texas Public Health Association, 
p. 112 (1933). 
DUGGEE, E. F. 
149. Should plumbing installation be approved by the water department. 
Journal, American Water Works Association, 30; 1775 (Nov. 1938). 
DUNLAP, J, H. 
150. Common sense, science and drinking fountains. 
American City, 20 : 470 (May 1919). 
151. The sanitary drinking fountain. 
Journal, American Water Works Association, 4: 65 (March 1917). 
EHLEBS, V. M., AND STEEL, E. W. 
152. Cross-connections in plumbing. 
Municipal and Rural Sanitation, McGraw-Hill, New York, N. Y., p, 280 
(1937). 95 
EHLERS, V. M., AND TURNED, 0. 
153. Cross-connections. 
Proceedings, Eighteenth Annual Texas Water Works Short School, p. 85 
(1936). 
ELLMS, J. W. 
154. The cross-connection problem. 
Fifteenth Annual Report of the Ohio Conference on Water Purification, 
Cleveland, Ohio, p. 36 (Oct. 1935). 
EL PASO, TEXAS 
155. Cross-connection items. 
El Paso, Texas, Plumbing Ordinances, Sections 22, 25 (c), (d), (i) and (n) ; 
and 26 (a) to (p). 
FAIK, G. M. 
156. The flush valve. 
Journal, New England Water Works Association, 35: 137 (June 1921). 
FERGUSON, G. H. 
157. Cross-connection dangers in plumbing. 
Canadian Public Health Journal, 24: 580 (Dec. 1933). 
PEILITZCH, baxjrat V. 
158. Tiber eine neue Druckspiilerausfiihrung. 
Das Gas- und Wasserfach, 75: 218 (Mar. 19, 1932). 
FISHER, L. M. 
159. Cross-connections. 
Proceedings, Ninth Annual Meeting, Florida Section, American Water Works 
Association (Mar. 1935). 
FLETCHEK, A. H. 
160. Quasi-public water supplies and cross-connections with municipal water 
supplies. 
Journal, American Water Works Association, 29: 78 (Jan. 1937). 
FOLEY, A. E., FAILE, J. L., AND BEANDON, K. F, 
161. Hospital plumbing epidemic of paratyphoid A. 
Canadian Public Health Journal, 27: 313 (July 1936). 
FKOMMELT, HORACE A. 
162. Is the schoolhouse plumbing safe? 
American School Board Journal, 90: 21 (May 1935). 
GEIGER, J. C., BECKER, G. H., AND GRAY, J. P. 
163. Epidemiology of amebiasis. 
American Journal of Public Health, 25: 389 (Apr. 1935). 96 
GOGLIA, M, C. 
164. The relation of plumbing to public health. 
Philadelphia Department of Public Health Monthly Bulletin, p. 37 (Apr, 
29). 
GOEMAN, A. E. 
165. Cross-connections in Chicago. 
Journal, American Water Works Association, 15: 587 (June 1926). 
GOUDEY, E. F., AND SIANE, N. F. 
166. Dangers of back-siphonage of contaminated air. 
Municipal Sanitation, 7; 437 (Dec. 1936). 
GROENIGEK, W. C. 
167. Typhoid fever outbreak on Manhattan St., Middleton, Ohio, and its cause. 
Pamphlet, 15 pp. (1938). 
168. A discussion of facts relating to the problem of cross-connections caused 
by under rim inlet water-supplied plumbing fixtures. 
Proceedings, American Society of Sanitary Engineering, 17: 25 (1933- 
1935). 
169. Elimination and prevention of health hazards caused by cross-connections. 
Proceedings, American Society of Sanitary Engineering, 17: 367 (1933- 
1935). 
170. Plumbing in hotels. 
Proceedings, American Society of Sanitary Engineering, 17: 654 (1933- 
1935). 
171. History and performance of water closet bowls. 
Proceedings, American Society of Sanitary Engineering, 16: 115 (1932). 
172. A menace to the public health that means more work for contractors. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 92: No. 9: 19 (Nov. 1, 1931). 
173. Report of research committee of American Society of Sanitary Engineer- 
ing. 
Pamphlet, 21 pp. (Sept. 9, 1931). 
174. Where the siphon and siphonage make sanitary plumbing fixtures insani- 
tary and how cross-connections can be avoided and corrected. 
Proceedings, American Society of Sanitary Engineering, 15: 75 (1930- 
1931). 
175. Check valves as siphon preventers. 
Proceedings, American Society of Sanitary Engineering, 15: 90 (1930-1931). 
176. Cross-connections. 
Proceedings, American Society of Sanitary Engineering, 15: 239 (1930- 
1931) ; also 14: 75 and 158 (1928-1929). 
177. Problems in cross-connections. 
Municipal Sanitation, 1: 250 (May 1930). 
178. The contamination of water supply through cross-connections. 
Plumbers and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 86: No. 1: 18 (Jan. 1, 1929). 
179. Pollution of domestic water supplies through unusual cross-connection. 
American City, 39: 96 (Sept. 1928). 97 
180. Insurance against water-borne diseases through plumbing fixtures. 
Proceedings, American Society of Sanitary Engineering, 13: 203 (1926- 
1927) ; also, Plumbing and Heating Trade Journal (now Plumbing and 
Heating Journal), 83: 506 (Sept. 1, 1927). 
HALPIN, H. E. 
181. Tanks for water service in high buildings. 
Journal, New England Water Works Association, 51: 273 (Sept. 1937). 
HANSEN, PAUL 
182. Unsuspected, unusual, and little known factors in water supply quality. 
Journal, American Water Works Association, 24: 1780 (Nov. 1932). 
HARDY, A. V., AND SPECTOR, B. K. 
183. The occurrance of infestations with E. histolytica associated with water- 
borne epidemic diseases. 
Public Health Reports, 50 : 323 (Mar. 8, 1935). 
HARRINGTON, A. V. 
184. Special equipment cross-connections. 
Journal, New England Water Works Association, 51: 270 (Sept. 1937). 
HATCHEE, M. P. 
185. Essential factors in design of swimming pools. 
Municipal Sanitation, 2: 347 (July 1931), 
HENDERSON, C. J. 
186. Pollution of domestic water supply. 
Proceedings, American Society of Sanitary Engineering, 13: 47 and 224 
(1926-1927). 
HINMAN, JACK J. 
187. Menace to consumers through faulty plumbing. 
Water Works Engineering, 88: 1355 (Nov. 27, 1935). 
HOLMQUIST, C. A., AND DEVENDORF, EARL 
188. Safeguarding and eliminating cross-connections in New York State. 
Journal, American Water Works Association, 22: 103 (Jan. 1930). 
HOUSTON, TEX. 
189. Water supply cross-connections. 
Houston, Tex., plumbing ordinance, Section 9, Par. (q), 1931. 
HOWARD, CHARLES D. 
190. New plumbing code adopted. 
New Hampshire Health News, 16: 4 (Apr. 1938). 98 
HUNTER, E. 8., GOLDEN, G. E., AND EATON, H. N, 
191. Cross-connections in plumbing systems. 
Journal of Research, National Bureau of Standards, 20 : 479 (Apr. 1938). 
INDIANA STATE BOARD OF HEALTH 
192. Cross-connections in gas refrigerators. 
Monthly Bulletin, Indiana State Board of Health, 33: 61 (Apr. 1930). 
193. Swimming pool regulations. 
Monthly Bulletin, Indiana State Board of Health, 33 : 209 (Jan. 1930). 
194. Plumbing the situation. 
Modern Hospital, 47: No. 4: 94 (Oct. 1936). 
JOHNSON, W. SCOTT 
195. Plumbing hazard survey of pasteurization plants. 
American Journal of Public Health, 26: 229 (Mar. 1936). 
196. A survey of potential health hazards due to faulty plumbing. 
Journal, American Water Woi’ks Association, 28: 214 (Feb. 1936). 
KAUNSKE, A. A., DAWSON, F. M., AND KING, F. E. 
197. Cross-connections in plumbing and water supply systems. 
Bulletin, Wisconsin State Board of Health and the University of Wis- 
consin, 76 pp. (1936). 
KALINSKE, A. A., AND MCLEOD, A. M. 
198. All “anti-siphon” traps siphon if unvented. 
Plumbing and Heating Business, 1: No. 4: 27 (Dec. 1938). 
KEGEL, ARNOLD H. 
199. The relationship of hospitals to the health departments of large cities. 
Transactions, American Hospital Association, 31: 33 (1929). 
200. Faulty plumbing as a source of infection. 
Plumbers and Heating Contractors Trade Journal (now Plumbing and 
Heating Journal), 86: 246 (Feb. 1, 1929). 
201. Contamination of water in hospitals as a cause of post-operative infections. 
Transactions, American Hospital Association, 30: 575 (1928) 
202. Versuche mit AbortspiilMhnen und Bemessung der Hauleitungen. 
Das Gas- und Wasserfach, 75: 7 (Jan. 2, 1932), 
KELTIN6, OTTO 
KESSLER, LEWIS H. 
203. Hydraulics in small house plumbing. 
Proceedings, American Society of Sanitary Engineering, 17: 215 (1933- 
1935). 
KING, F. B. 
204. Report of Bureau of Plumbing and Sanitary Engineering. 
Wisconsin State Board of Health, p. 151 (1933). 99 
KOELUSCH, F. J, 
205. President vetoes Congress demand for U. S. survey as faulty plumbing in 
national capitol is revealed. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 98: No. 6: 25 (June 1935). 
LAWRENCE, K. E. 
206. A study of defects in hospital sterilization practise. 
Journal, Kansas Medical Society, 33: 200 (June 1932). 
LINK, E. 
207. Spiilbahnen mit Robrnnterbrecher fiir Abortspiilleitungen. 
Das Gas- und Wasserfach, 72: 489 (May 25, 1929). 
MAGATH, THOMAS B. 
208. The water transmission of infections with special reference to amebiasis. 
Journal, American Water Works Association, 27: 63 (Jan, 1935). 
MANOBA, M. 
209. The problem of cross-connection: an appeal to the medical profession. 
Journal, Philippine Island Medical Association, 16 : 235 (Apr. 1936). 
MARTIN, P. J., JR. 
210. Cross-connections discovered by water system survey at Tucson. 
Water Works Engineering, 8-7: No. 20: 1124 (Oct. 3, 1934). 
MASSACHUSETTS, COMMONWEALTH OF 
211. Cross-connections. Report of the special commission to study and investi- 
gate public health laws and policies. 
House Document No. 1200, p. 110 (Dec. 1936). 
MATTHIESON, H. H. 
212. Outlawing cross-connections. 
Proceedings, American Society of Sanitary Engineering, 17 : 891 (1933- 
1935). 
MCAFEE, H. D. 
213. Correction of faulty plumbing. 
Journal, American Water Works Association, 28: 935 (July 1936). 
MCCOY, G. W., AND CHESLEY, A. J. 
214. Control of amebic dysentery. 
Journal, American Medical Association, 103: No. 15: 1145 (Oct. 13, 1934). 
MCGONEGAL, A. R. 
215. Use of water for air conditioning and refrigeration. 
Proceedings, 9th Annual Conference, Maryland-Delaware Water and Sewage 
Association, p. 106 (1935). 100 
216. “Amebiasis”—black eye or bull’s eye for the plumbing trade. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal) 
96: No. 3: 17 (Mar. 1934). 
217. Beer equipment installations and the menace of cross-connections. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal) 
94: No. 5: 50 (May 1933). 
218. Menace of cross-connections seen in faulty wastes of refrigerators. 
Plumbing and Heating Contractors Trade Journal (now Plumbing and Heat- 
ing Journal), 93: No. 5: 55 (Aug. 1932). 
MENDELSOHN, I. W., SCHWARTZ, LOUIS, AND FERGUSON, G. H. 
219. Water-borne disease epidemics on ships. 
Journal, American Water Works Association, 21: 1660 (Dec. 1929). 
MENGEBINGHAUSEN, M. 
220. Grundlagen fur die Berechriung von Hauswasserleitungen. 
Das Gas- und Wasserfach, 75: 865 (Oct. 29, 1932). 
MILLER, ARTHUR P. 
221. Plumbing hazards and their evaluation. 
Journal, American Water Works Association, 30: 1702 (Oct. 1938). 
MILLER, A. P., AND CRONKRIGHT, ARTHUR B. 
222. Administrative actions directed at removing plumbing interconnections. 
Plumbing and Heating Business, 1: No. 9; 23 and 1: No. 10: 21 (May and 
June 1939). 
223. Wide research proved need for better plumbing fixtures. 
Plumbing and Heating Business, 1: No. 7: 25 and 1: No. 8: 26 (Mar. and 
Apr. 1939). 
224. Interconnections in plumbing. 
Plumbing and Heating Business, 1: No. 5: 25 and 1: No. 6: 27 (Jan. and 
Feb. 1939). 
225. The public health significance of modern plumbing. 
Plumbing and Heating Business, 1: No. 4: 14 (Dec. 1938). 
MINNESOTA DEPARTMENT OF HEALTH 
226. Plumbing in relation to public health. 
State Board of Health Bulletin (1938). 
227. Report of investigations of the typhoid fever epidemic, Minneapolis. 
Plumbing Surveys, Part 11, p. 56 (1935). 
MORRIS, S. B. 
228. Cross-connections with reference to plumbing fixtures and devices. 
Water Works Engineering, 85; 1437 (Nov, 30, 1932). 
229. Cross-connections with public water supplies. 
Journal, American Water Works Association, 24: 1750 (Nov. 1932). 
230. Contamination of water systems by consumers’ water uses. 
Journal, American Water Works Association, 22: 180 (Feb. 1930). 
231. Main pollution by water which has passed services. 
Water Works Engineering, 82: 1689 (Nov. 20, 1929). 101 
MOWEY, C. W. 
232. Status of cross-connection regulations. 
Journal, New England Water Works Association, 49: 66 (March 1935). 
MURDOCH, W. A. 
233. 102,492 water supply danger points found in 980 hotels. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 98: No. 3: 40 (Mar. 1935). 
MURPHY, F. M. 
234. Plumbing and its relation to health. 
Proceedings, Seventeenth Annual Texas Water Works Short School, p. 60 
(1935). 
NATIONAL INSTITUTE OF HEALTH 
235. Epidemic amebic dysentery. 
National Institute of Health Bulletin No. 166 (1936). 
NEW BEDFORD, MASSACHUSETTS 
236. Regulations governing water service supply piping and fixtures. 
New Bedford, Mass., Water Department (June 1, 1935). 
NEW ENGLAND WATER WORKS ASSOCIATION 
237. The advisability of water departments regulating water piping and fixtures 
within buildings. (Committee Report.) 
Journal, New England Water Works Association, 51: 259 and 476 (Sept, and 
Dec. 1937). 
238. Report of Committee No. 8 on cross-connections. 
Journal, New England Water Works Association, 26: 1836 (Dec. 1934). 
NEW YORK STATE DEPARTMENT OF HEALTH 
239. Faulty plumbing installations—a public health problem. 
Health News, New York State Department of Health, 13: No. 21; 82 
(May 25, 1936). 
240. Elimination of health hazards caused by faulty plumbing installations and 
fixtures. 
New York State Department of Health Bulletin No. 28 (1934). 
241. Health hazards of cross connections in buildings. 
Health News, New York State Department of Health, 10: No. 48: 189 
(Nov. 27, 1933). 
242. Unusual sources of water pollution. 
Health News, New York State Department of Health, 7: No. 7: 27 (Feb. 
17, 1930). 
OLD, H. N. 
243. Some aspects of interstate carrier water-supply certification. 
Proceedings, 7th Annual Meeting, Southeast Section, American Water Works 
Association, 5: No. 1: 20 (1935). 102 
OLESEN, KOBEBT, AND EOSENBLUTH, JACOB 
244. A note on the incidence of amebic dysentery in New York City. 
Public Health Reports, 50: No. 2: 37 (Jan. 11,1935). 
O’NEILL, J. H. 
245. Dangerous plumbing. 
Louisiana State Board of Health, Quarterly Bulletin, 26: 4 (June 1935). 
OTT, O. W. 
246. Laboratory tests disclose of back-siphonage. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Journal), 
97: No. 1: 30 (July 1934). 
247. Back-siplionage. 
Western Plumbing and Heating Journal, p. 3 (Nov. 1933). 
OTT, O. W., AND MATTHIESON, H. H. 
248. Why back-siphonage? 
Proceedings, American Society of Sanitary Engineering, 17: 57 (1933-1935). 
249. The bacteriology of the bubble fountain. 
Journal of Bacteriology, 1: No. 5; 471 (Sept. 1916). 
PBTTIBONE, DOROTHY F., BOGART, FRANKLIN 8., AND CLARK, PAUL F. 
PUBLIC HEALTH SERVICE, U. S. 
250. Public health hazards in plumbing. 
Domestic Quarantine Division, U. S. Public Health Service, processed 
pamphlet, 37 pp. (Dec. 1937). 
PUTNAM, WALTER 
251. Possible pollution of water through use of toilet flush valves. 
Journal, California Sewage Works Association, 5: No. 1: 106 (1932-1933). 
EADDEE, NOEMAN. J. 
252. Cross-connections in plumbing. 
Hotel Management, 37: 264 (Apr. 1935). 
253. Plumbing modernization from the standpoint of health. 
Building and Building Management, 35: No. 2: 84 (Jan. 16, 1935). 
RAWLINGS, I. D., AND FERGUSON, H. F. 
254. Responsibilities of municipalities, water companies, and individuals for 
water-borne illness. 
Journal, American Water Works Association, 16:415 (Oct. 1926). 
BEEVES, HUBERT A. 
255. Correctly designed water pipes—a safeguard against back-siphonage. 
Western Plumbing and Heating Journal, 19: 227: 5 (Nov. 1938). 103 
256. Amebic dysentery. 
Journal, Pennsylvania Water Works Operators’ Association, 6: 60 (1934). 
EICE, J. W. 
BIKEK, I. BUSSELL, AND NICHOLS, CHABLES M. 
257. Physical connections to public potable water-supply systems in New Jersey. 
Health News, New Jersey Department of Health, 14: 3-4: 68 (Feb.-Mar. 
1929). 
ROBERTS, F. C., JR. 
258. Protection from water-closet cross-connections. 
Arizona Public Health News No. 113 (July 1935). 
EODIEK, H. 
259. Rollrbeliifter (Rohrunterbrecher) als Scbutz der Reinwasserleitungen gegen 
Riicksaugen. 
Das Gas- und Wasserfach, 78 : 949 (Dec. 21, 1935). 
260. Cross-connections in a soda fountain. 
Domestic Engineering, 131: No. 3:75 (May 3, 1930). 
ROSS, ROBERT M. 
SCHULZE, WILMER H., AND REYNOLDS, C. H. 
261. The prevention and elimination of potential cross-connections in plumb- 
ing installations. 
Proceedings, Tenth Annual Conference, Maryland-Delaware Water and 
Sewerage Association (1936). 
262. Cross-connections—a potential menace to health. 
Maryland Master Plumber, 9: No. 8: 5 (Jan. 1935). 
263. An educational program for the prevention and elimination of cross- 
connections in Baltimore. 
Proceedings, American Society of Sanitary Engineering, 17: 874 (1933- 
1935). 
SCOTT, W. J. 
264. How to make cross-connection surveys. 
Journal New England Water Works Association, 49: 354 (Dec. 1935). 
265. Cross-connections in Connecticut. 
Journal, New England Water Works Association, 41: 365 (Dec. 1927). 
SHERMAN, L. K. 
266. Cheeking indoor water pollution. 
Connecticut Health Bulletin, 52: No. 2: 43 (Feb. 1938). 
267. Plumbing fixtures subject to back-siphonage. 
Journal, New England Water Works Association, 51: 266 (Sept. 1937). 
STANDARDS, BUREAU OF 
268. Recommended minimum requirements for plumbing. (Report of sub- 
committee on plumbing of the Building Code Committee.) 
U. S. Department of Commerce, 283 pp. (Mar. 5, 1932). 104 
269. Recommended minumum requirements for plumbing in dwellings and 
similar buildings. (Final committee report.) 
Bureau of Standards (July 3, 1923). 
STARBUCK, R. M., JB. 
270. Sanitary connections for bars. 
Domestic Engineering, 143: 141 (Mar. 1934). 
271. Dangers of cross-connections. 
Domestic Engineering, 127: No. 6: 53 (June 15, 1929). 
STATE SANITARY ENGINEERS, CONFERENCE OF 
272. Essential features in design of sanitary drinking fountains. 
Transactions, 13th annual conference, State Sanitary Engineers, p. 55 (Oct. 
1932). 
273. Report of Committee on Cross-connections. 
Transactions, tenth annual conference, State Sanitary Engineers, p. 35 
(Sept. 1929). 
274. Importance of good plumbing properly installed. 
Tbe Valve World, 38: No. 1; 17 (Jan. 1936). 
STINE, L. B. 
SWANSON, A. E. 
275. Camera helps inspector enforce plumbing law. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 101: No. 4: 50 (Oct. 1936). 
TAYLOE, STEPHEN H. 
276. Water department regulation of pipes within buildings. 
Journal, New England Water Works Association, 50: 129 (June 1936); 
also, Water Works and Sewerage, 83: 78 (Mar. 1936). 
277. Water department responsibility for house water supply plumbing. 
Water Works Engineering, 89: 275 (Mar. 4, 1936). 
THOMSON, T. N. 
278. The practical application of modern plumbing specialties. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 103: No. 3: 98 (Sept. 1937). 
279. Look behind the fixtures as you modernize plumbing. 
Plumbing and Heating Trade Journal (now Plumbing and Heating Jour- 
nal), 97: No. 4: 43 (Oct. 1934). 
280. Cross-connections and their public-health significance. 
North Dakota Water and Sewage Works Conference Official Bulletin, 2: 11 
(June 1936). 
TOMAN, G. J, 
TYLER, E. Q. 
281. Cross-connections in plumbing as a health menace. 
Massachusetts Institute of Technology Publications, 65: 45 (1929). 
282. Textbook of sterilization. 
American Sterilizer Company, Erie, Pa., p. 116 (1934). 
UNDERWOOD, W. B. 105 
283. Field experiments in problems of water contamination from private flush 
valves. 
Journal, California Sewage Works Association, 5: 110 (1932-1933). 
VINCENZ, J. L. 
WARING. F. H. 
284. Proper water supply and drainage piping for hotels. 
Journal, American Water Works Association, 28: 242 (Feb. 1936). 
WECKWEBTH, F. 
285. Sicherungen der Trinkwasserleitungen gegeu Riicktritt von Warm- und 
Abwasser. 
Das Gas- und Wasserfach, 78: 687 (Sept. 7, 1935). 
WHITE, H. L. 
286. Cross-connection and plumbing fixture studies. 
Journal, American Water Works Association, 25: 922 (July 1933). 
WHITTAKER, H. A. 
287. Drinking fountains—investigations of fountains at the University of 
Minnesota. 
Public Health Reports, 32; 19: 691 (May 11, 1917). 
WILSON, E. CLEM 
288. Back siphonage of flush valves—causes and remedies. 
Los Angeles, Calif., pamphlet, 38 pp. (Feb. 1935). 
289. Defective plumbing. Editorial. 
Municipal Sanitation, 6: 291 (Oct. 1935). 
290. Verticle towns. Editorial. 
Municipal Sanitation, 5: 45 (Feb. 1934). 
WOLMAN, ABEL 
WOLPERT, N. N. 
291. Piping sickness to consumer. 
Water Works Engineering, 86 ;779 and 823 (Aug. 9 and 23, 1933). 
292. Controlling cross-connections. 
Water Works Engineering, 86: 728 (July 26, 1933). 
293. Disease-spreading installations. 
Water Works Engineering, 86: 633 and 678 (June 28 and July 12, 1933). 
294. When good water becomes bad. 
Water Works Engineering, 86: 586 (June 14, 1933). 
ZINKXL, E. H. 
295. Liberal size piping provides the answer to many back-flow problems. 
Plumbing and Heating Business, 1: No. 3: 29 (Nov. 1938). 
296. Safe air gaps to prevent back-siphonage. 
The Valve World, 33: No. 4: 133 (Oct. 1936). 
297. Value of a testing laboratory in development of plumbing fixtures. 
Proceedings, American Society of Sanitary Engineering, 17: 81 (1933- 
1935). 
218645—40 8 APPENDIX A 
SURVEY QUESTIONNAIRE 
Name ol Duilding Date 
Address Chief of party 
Description of building Sanitary engineers 
Age years 
Summary: Report of plumbing inspection, date 
DEFICIENCIES 
Cross-connections 
Submerged supplies 
Defective plumbing 
Bathtubs 
Soil pipe 
Laundry washers 
Vent pipe - 
Soup kettles 
M iscellaneous. 
Dish washers 
TANKS 
Number and size of meters Fish traps Filtered 
Valved Treated 
Check valves Temperature °F. 
Condition Residual chlorine ppm. 
Pressure lbs. Sample 
CITY WATER SUPPLY 
Average analysis of samples 
B. coli in 100 ce. 
Bact. Ct. Agar 
37° C., 24 hours 
Per cc. 
Main feeder line: Size Termination 
BRANCHES FROM MAIN FEEDER 
Size 
Service 
Size 
Service 
Branch No. 1_ 
Branch No. 2 __ 
Branch No. 3 
Branch No. 4 107 
Are there any bleeders? Valved To where? 
Cross connected with any other system 
Are there any lines dead or dead-ended 
Sketch Remarks 
HOUSE PUMPS 
Source of supply Temperature °F. 
Capacity 
Suction 
pressure 
Discharge 
pressure 
Power 
Type 
Gallons per 
minute 
Pounds 
Pounds 
Pump No. 3... 
Note.—(If from wells, give additional information under Well Water Supply.) 
Are pumps primed? From what source 
Are house pumps serving as standby for any other pumping unit? 
Detail 
Any other source of supply to pumps? Detail 
Wliat part of house is served by house pumps direct? 
What units are served by house pumps direct? 
Are all house pumps directly connected with house tanks? 
Can house tanks be shut off from pumps? 
Are house pumps actuated by control from house tanks? 
Sketch Remarks 
Type and kind 
Purpose 
Primed 
Capacity 
Discharge 
pressure 
1 
2 
3 
4 
5 
Oals.per min. 
MISCELLANEOUS PUMPS 
Temperature 0 F. 
Residual chlorine ppm. 
Sample 
Sketch 
Average analysis of samples 
Pump No. 
B. coll in 100 
CO. 
Bact. Ct. Agar 
37° C., 24 hours 
Per cc 
Remarks 
HOUSE WATER SUPPLY 
Source 
(If from wells, see Well Water Supply). 108 
Pressure lbs. 
Temperature 0 F. 
Residual chlorine ppm. 
Sample 
Filtered 
Treated 
Average analysis of samples 
B. coli in 100 cc. 
Baet. Ct. Agar 37° C., 
24 hours 
Per cc. 
Are all bathrooms and toilets served by one water line in each shaft? If 
two lines are used, is one line to flush valves on a separate tank? Detail 
Condition of piping Valves 
Is house water supply cross connected with any other system? 
Sewers? Tanks? Drains? Other? 
Are there any bleeders? Valved? to where 
What units are supplied? 
Are all discharges from units so arranged to prevent back pressure or syphonage? 
Are any water lines drained to sewer? Detail 
What pumps have primer lines? 
Detail 
What pressure units have water connections? 
Detail 
Are any lines to units submerged? 
Detail 
Are water inlets to air washers above pan? 
Detail 
Are there any dead end lines? 
Sketch Remarks 
No. Kind Cover Kind 
Capacity Condition 
Location 
Height above street level Overflow to 
Inlet submerged Drain to 
Sketch Remarks 
HOUSE TANKS 
Temperature °F. 
Residual chlorine PPm 
Sample 
Average analysis of samples 
Tank No. 
B. coli in 100 cc. 
Bact. Ct. Agar 
37° C., 24 hours 
Per cc. 
Note.—If more than one tank, use separate sheet for each tank. 
Size Capacity Overflow 
Location 
Covered Kind 
SURGE TANKS 109 
Temperature °F 
Residual chlorine ppm 
Sample 
Average Analysis of samples 
B. coll in 100 cc. 
Bact. Ct. Agar 37° C., 
24 hours 
Per cc. 
What lines discharge into surge tank? From what units? 
gallons per minute for each line 
What is this water used for? 
Recycle pump size Capacity Discharge pressure 
Is discharge line cross connected with any other system? 
Sketch Remarks 
Source 
Filtered 
Treated 
Cooled 
Temperature °F. 
Residual chlorine ppm 
Pressure 
Sample 
DRINKING WATER SYSTEM 
Average analysis of samples 
B. coli in 100 cc. 
Bact. Ct. Agar 37° C., 
24 hours 
Per cc. 
Give general description of filtering system 
Where are drains from filter discharged? 
Has this system separate piping with tank and return? 
Detail 
Cross connected with any other system? 
Bleeders Valved to where 
Sketch Remarks 
WELL WATER SYSTEM 
Location of well , 
Depth Size and kind of casing 
Condition Type of pump Capacity 
Discharge pressure Purpose for which water is used 
Filtered 
Treated , 
Cooled 
Average analysis of 
samples 
B. coli in 100 cc. 
Bact. Ct. Agar 37° C., 
24 hours 
Per cc. 
Cross connected with any other system 
Detail 
Sketch Remarks 
FIRE AND SPRINKLER SYSTEMS 
Source Separate tank Capacity Location __ 
Fire pump capacity Discharge pressure 
Suction pressure Is this system cross connected with any other system 
Are there any bleeder lines Yalved to where 
Sketch Remarks COOLERS AND CONDENSERS 
Refrigerators Water required gpm. Source 
Temperature on °F. off °F. 
Size inlet outlet Discharge to 
Discharge bypass to 
Detail 
SEWERS AND SEWERAGE 
Size street sewer Size house sewer Material 
Gradient house sewer Vents Size 
Location 
Condition 
Remarks 
Outside building line 
Inside building—house drains 
1. Location 
Material Size Condition 
Number of stacks served Total units on stacks 
Total units on drain Probable slope 
Are there any traps? Cleanouts Vents 
Is drain cross connected with any other system? 
Details and sketch 
Remarks _ 
2. Location 
Material Size Condition 
Number of stacks served Total units on stacks 
Total units on drain Probable slope 
Are there any traps? Cleanouts Vents 
Is drain cross connected with any other system? 
Details and sketch 
Remarks 
3. Location 
Materials Size Condition 
Number of stacks served Total units on stacks 
Total units on drain Probable slope 
Are there any traps? Cleanouts Vents 
Is drain cross connected with any other system? 
Details and sketch 
Are any house drains over or near food handling? 
Rooms 
served 
Size 
Material and 
condition 
Total fixtures 
I 
2 
3 .. 
4 
5 
C_- 
7.... 
8 
9 
10 
STACKS 
What lines or units drain into stacks other than fixtures? 
List downspouts which are separate from stacks: 
Size Area served sq. ft. Condition 
Size Area served sq. ft. Condition 
Size Area served sq. ft. Condition 
Size Area served sq. ft. Condition Are stacks in open shafts? 
Hydraulic test—Stack No. of fixtures used gpm. 
Hydraulic test—Stack No. of fixtures used gpm. 
Hydraulic test—Stack No. of fixtures used gpm. 
Hydraulic test—Stack No. of fixtures used gpm. 
Remarks on tests—Data 
Sketch Remarks 
VENTS AND KEVENTS 
Condition Open through roof 
Are shafts open to atmosphere Protected 
Remarks 
Units served: 
Floor Discharge to 
Ice box Discharge to 
Water-cooled bearings Discharge to 
Hot water heater Discharge to 
Flexible hose Discharge to 
Hydraulic elevator Discharge to 
Sketch Remarks 
DRAINS 
Location 
Type and kind of ejector 
Type and kind of sump pump 
Purpose used 
Size discharge line 
Condition 
Are pumps primed 
Detail Remarks 
EJECTORS AND SUMPS 
OTHER DATA 
For Hospitals, Institutions, Etc. 
INSTRUMENT STERILIZERS 
1. Make 2. Make 
Location of water inlet Location of water inlet 
Outlet Outlet 
Water bleeder Water bleeder 
Vacuum breaker Vacuum breaker 
Drain connection protected Drain connection protected 
Steam outlet vented Steam outlet vented 
WThere Where 
Steam outlet protected Steam outlet protected 
Drain protected Drain protected 
Drip seal Drip seal 
If vented, where to? If vented, where to?__ 
PRESSURE STEAM STERILIZERS (AUTOCLAVES) 112 
WATER STERILIZERS 
Water supply inlet Protection 
Filter Protection 
Cooling coil drain Protection 
Reservoir drain Protection 
BEDPAN STERILIZERS 
Make Water or steam inlet location Protection 
Type of valve Flushometer Vacuum breaker 
Location of V. B. on inlet or outlet side Make 
Approximate area of air vent 
Make Continuous flow Protection 
Fiush valve protected Condition 
SPECIAL BATHS 
Aspirators Protected 
Heaters Protected 
LABORATORY EQUIPMENT 
Table drain Protected 
Flush valve protected 
AUTOPSY ROOM 
OTHER DATA APPENDIX B 
INSTRUCTIONS FOR PREPARATION OF PLUMBING INSPECTION 
REPORTS 
DEPARTMENTAL REPORTS 
The general report to the Federal department having jurisdiction 
over the buildings inspected will deal briefly with the history of the 
project, its purpose and objective. 
This will be followed by general remarks on dangers of cross- 
connections and back-siphonage. It will call attention to experience 
gained through the Chicago amebic dysentery outbreak that chlorina- 
tion alone is insufficient when the water supply is subject to initial 
contamination at its source or to recontamination through cross- 
connections and back-siphonage in the distribution systems. 
The dangers accompanying improperly located and defective sewers 
Avith relation to water distribution systems and food handling estab- 
lishments will be pointed out. These general remarks will be in 
sufficient detail to make it unnecessary to specify in the detailed 
plumbing report why certain cross-connections, submerged orifices in 
lavatories, bathtubs, sterilizers, etc., and simple flushometers are to 
be viewed with alarm. 
Following the general remarks in the departmental report will be 
the map showing the group locations of all Federal buildings in the 
city, with a list of the groups under the jurisdiction of this particular 
department. 
After this the group reports will follow in numerical order, such 
group report having a title page showing the number, name, and 
address of the group and will be separated from other groups by a 
colored onion skin sheet. 
A general summary will follow. This will be a summation of all of 
the corrections which are recommended for each group under the 
jurisdiction of this department. 
GROUP REPORTS 
Building list.—Following the title page of the Group Report as 
mentioned under Departmental Reports, when the group consists of 
more than one building, there will follow a list of buildings and struc- 
tures in the group. All buildings listed having no plumbing will be 114 
indicated by an asterisk following tlie unit number. This list may 
or may not be a part of the group map. 
Group 7nap.—The Group Map will show the relative location of 
each building or structure in the group. Where it is necessary to 
illustrate certain deficiencies or violations outside of the building, in 
the water and sewer lines, the latter will be shown on the Group 
Maps. 
Engineering survey.—lf the group involves more than one building, 
having a common source of water supply, sewerage or sewage dis- 
posal system, there should be inserted here a description of the water 
supply, its source and method of distribution; and of the sewerage 
system, including the final treatment and disposal of the sewage, when 
this disposal is other than through the city sewers. 
If the group consists of only one building, the general information 
regarding source of water supply and sewage disposal may be 
included under Building Report described hereafter. The individual 
building reports should follow one another in numerical order as 
they appear on the building list; excluding these which are marked 
as having no plumbing. 
Group summar-y.—Following the Building Reports there should be 
a group summary of corrections recommended for each building 
which will show the total number of corrections of the group. 
BUILDING REPORT 
In making field inspections the detail survey blanks should be 
frequently consulted. Each question presented may have some spe- 
cial use in locating defects and making corrections, and should be 
carefully weighed as to its importance in connection with the survey 
of the building under consideration. 
Page 1 on the building report will follow the general summary 
sheet used on the survey blanks except that irrelevant matter will 
be excluded. The group and unit numbers will be shown in the 
upper right-hand corner of the sheet. The name of the building, 
address, use, description, and age of building will be given, and the 
chief of party and sanitary engineers responsible for making the 
inspections will also be shown. 
The date will show the day of beginning and the day of completion, 
marking the period covered by the inspection. 
A summary will then be given of all deficiencies in the building, 
listed by numbers only. The classifications of deficiencies as given 
in the original survey blanks will be maintained, namely, cross- 
connections, submerged supplies, defective plumbing, faulty drinking 
fountains, and tanks. No attempt will be made in this summary to 
describe any deficiency except to show that one exists; the later 115 
sections of the report will include all of the details. Ice boxes, auto- 
claves, and other equipment having no water connection, which are 
directly connected to vent or waste lines of the sewer system, will 
be listed under miscellaneous defective plumbing. 
When the plumbing in the building is limited and has no defects 
or only has a limited number a single sheet may be all that is nec- 
essary for a complete report. The data on water supply and the 
sewerage system for the group must be contained in the general in- 
formation for the group and no repetition will be necessary here. 
In large buildings the second page of the building report will 
begin with a full description of the water supply and sewerage 
systems. 
A description of the water supply should include the source, num- 
ber and sizes of meters, size of intake lines, and the general method 
of supplying water to the building. For example, if the entire build- 
ing is under city pressure, this should be stated, and if a portion of 
the building is under city pressure and booster pumps are used for 
maintaining service to other portions of the building, this should be 
described. The description should give a clear picture of the method 
of distributing water to all floors of the building. 
If there is a separate drinking-water system it should be described 
giving its relation to the cold-water system mentioned above. 
A general description should be given of the hot-water system and 
its source. 
This should be followed by a description of the fire and sprinkling 
system, giving the source of water, and its connection with other 
water services. 
If air-conditioning apparatus is in use describe it and its relation 
to the water and sewer systems. The same applies to condenser and 
cooling systems. 
Include in the report the relationship of roof drains and sanitary 
sewerage. If the two are combined point out the place of conver- 
gence and the adequacy of the outlet of the combined system. Include 
what can be learned of troubles encountered during heavy rainstorms, 
backing up of sewers, etc. 
A description of the sewer system will also include all pumps, 
ejectors, etc., used to facilitate the prompt disposal of sewage and 
storm drainage. 
This general description of the various water and sewer systems 
will be followed with a complete layout of the basement service 
piping. This includes hot and cold water, ice water, and sewerage. 
Fire lines need not be included unless they are supplied with water 
from a different source and are cross-connected with the approved 
house supply. Pipe sizes and valves should be shown on all sketches. 116 
Usually the entrance of water lines and discharge of sewers is through 
the basement and, therefore, this should give a good general picture 
of the systems involved. 
The basement sketch should show the services on all risers so that 
detailed sketches of cross-connections on upper floors may be iden- 
tified with certain lines. It will thus be unnecessary to show an 
entire line where there is probably only one faulty piece of appara- 
tus on it. The risers, water and sewage, can be numbered and the 
description of the services, by floors, can be shown on the sketch, or 
on an accompanying sheet. 
Drawings and sketches on the final report will be of the cabinet 
style rather than isometric; using horizontal, vertical, and 45° lines. 
The legend will be as follows: 
1. Cold water lines will be shown in solid black. 
2. Ice water lines will be shown in solid black with I. W. inserted 
in the lines at convenient points where this will not detract from 
the clarity of the drawing. 
3. Fire lines will be shown in solid black with a small F super- 
imposed at short intervals, when the course of the water is the same 
as that in cold water piping. 
4. When an auxiliary supply is used to service the fire lines they 
will be shown in red with a small F superimposed. 
5. Hot water lines will be shown by a long dash and two short 
dashes, in green. 
6. Supplementary water supplies will be shown by a long dash with 
three small dashes, in orange. 
7. Vent lines will be shown with a long dash and dot, in blue. 
8. Sewer lines will be shown with long dashes, in red. 
Field parties showing piping under 5,6, 7, 8 and 9 in color will use 
solid lines only. 
9. Storm drainage lines will be shown with long dashes, in brown. 
If water distribution lines and house drains are on different floors 
drawings should be made of each. 
When it is impossible to trace the water and sewer lines, because 
of concealed piping, their probable location should be shown on the 
sketches with broken lines. Sometimes original plans may be secured 
for use as a guide in locating concealed piping but these should not 
be used as a substitute for visual inspection where the latter is pos- 
sible. Information from this source must be shown with broken lines 
indicating that a visual inspection was not possible. 
The primary purpose of this survey is to locate actual and potential 
public health hazards in the plumbing systems in the buildings and 
the reservations inspected, and to recommend such changes as are 
necessary to eliminate them. All contaminating influences, through 117 
cross-connections, back-siphonage, air pollution, improper location of 
sewer lines, or other factors, which may affect the water supply, food 
supplies, or sterilizing fixtures shall be considered. 
In buildings which have been in use for a considerable length of 
time, where no difficulty has been experienced with stoppage, over- 
flows, and leakage and no defects measured by the previous para- 
graph are apparent to the inspection party, it will be assumed that 
stacks, vents, and soil lines are of ample size and are functioning 
properly. The sketches of sewer lines under such circumstances will 
be confined to the basement or lower floor collection system showing 
the location of risers and a list of the services connected thereto. 
Improperly located sewers should always be shown by sketches. 
The determination of such are the responsibility of the chiefs of party 
as no general rule applicable to all conditions can be stated. 
All actual or potential cross-connections between lines should be 
well illustrated by sketches in detail showing the undesirable features, 
and if possible an accompanying illustration showing a suitable cor- 
rection, Special fixtures should be illustrated by sketches, photo- 
graphs, or both, showing actual or potential hazards to public health. 
The common lavatories, bathtubs, laundry tubs, ordinary sinks, etc., 
should all be listed, giving their location in the building (by room 
number when possible), and the deficiencies, if any, with their con- 
nections. Toilets and urinals will be listed separately, giving location 
in the building, make and type of bowl or description of same; low or 
high tank, or flushometer; check valve and vacuum breaker (make 
and type), with corrections. 
A Building Report will close with a summation of all corrections 
recommended, including cross-connections, disapproved fixtures or 
defective plumbing. 
SUPPLEMENT TO INSTRUCTIONS FOR PREPARATION OF PLUMBING 
INSPECTION REPORTS 
All risers will be numbered. The number being preceded by the 
letter denoting the type of riser. Example: 
C = Cold water. 
H= Hot water. 
F= Fire line. 
S= Soil stack. 
L= Rain leader 
I. W. = Ice water. 
V= Vent. 
The hot and cold pipes that feed the same fixtures will have the 
same number wherever possible. 118 
Field sketches will be made of risers that feed a number of fixtures. 
This will not however exclude these particular risers from the list 
giving all risers and tabulations of all fixtures by floors on each riser. 
These field sketches will be for use in determining where to take water 
samples for analysis. In most instances, they will not be redrawn 
by the office draftsmen. 
It is desired that the final office drawings have all piping on one 
sheet, therefore it is well for the field parties to keep this in mind 
so that their cold, hot, sewer, etc. sketches may easily be assembled 
in the office. The direction of north should be indicated on each 
sketch. 
Basement plans redrawn by the office force will be checked in the 
office by the individual chiefs of party to see that they are in perfect 
agreement with their field sketches. The plans will then be checked 
by the office engineer. 
Detailed sketches of cross-connections etc. will first be checked by 
the office engineer and drawn up by the office draftsmen only after 
an O. K. by the office engineer. It is believed that this procedure will 
give the office draftsmen the least amount of redrawing. 
The office engineer is to go over all sketches and reports submitted 
and note missing data, details needing clarification, errors, disagree- 
ments, etc. These points will be taken up with and straightened out 
by the chiefs of party. 
The office engineer will then make up the final building report.