PROVISIONAL STANDARD, FOR FUMIGATION WITH HYDROCYANIC ACID GAS.
TREASURY DEPARTMENT

Bureau of the
United States Public Health Service,

Washington, Oct. 30, 1915.

Buresgu.Circular
Letter No. 79.

To Officers of the U. S, Public Health Service:

When performing the cyanide fumigation of compartments
you will be guided by the following minimum requirements:

1. On account of the great danger to human life from
nydrocyanic acid gas, specific arrangements should be made
for the disposition or the crew during the fumigation process,
especially if one or two compartments of a vessel are to be
treated. A written statement must be obtained from the captain
or first officer of the vessel that the latter is ready for
fumigation, and that every member of the crew has been account-
ed for as not being in the vessel, or else not exposed to the
fumes of the gas. Persons in one compartment have been killed
by fumes escaping from another compartment undergoing fumi-
gation.

2. Not less than 5 ounces of Potassium Cyanide, or 3%
ounces of Sodium Cyanide shall be used to each 1,000 cubic
feet of space, inclusive of that occupied by cargo.

5. To each ounce of Potassium Cyanide 1 fluid ounce of
commercial Sulphuric Acid 66B and 2% fluid ounces of water
shall be used.

4. To each ounce of Sodium Cyanide 1% fluid ounces of
Sulphuric Acid 66B and 2 fluid ounces of water shall be used.

oO. All ingredients shall be weighed and mixed immediately
prior to each fumigation.

6. All parts of the vessel shall be placed under fumi-
cation simultaneously except such compartments as may not re-
quire fumigation in the opinion of a representative of the
United States Public Health Service. (Review par. l).

7. All compartments placed under fumigation shall be kept
closed for not less than one hour.

8. The hatches of ‘tween decks and the doors of sub-
compartments are to be opened prior to fumigation, and the
barrel or other generator is to be placed so as to secure the
most rapid and efficient diffusion of the gas.

9. All work is to be done under the supervision and to
the satisfaction of the medical officer in charge, United
States Public Health Service, or his representative.

RUPERT BLUE,

Surgeon-General.