32 



with carbon tetrachloride it sells for from 6.4 to 9.9 cents per 

 pound, f. o. b. the factory, plus certain freight allowances. There 

 are approximately 10 pounds to the gallon. 



ETHYLENE OXIDE 



Ethylene oxide is a colorless gas at ordinary temperatures, but 

 below 50° F. it is a colorless liquid. It has a boiling point of about 

 57.2°, and therefore it can be used with success at temperatures 

 considerably below 70°. 



The concentrated vapor of ethylene oxide is inflammable, but 

 concentrations up to 3y 2 pounds per 1,000 cubic feet of space are 

 nonexplosive and noninflammable. 



A dosage of 2 pounds per 1,000 cubic feet will give satisfactory 

 results in a tight vault, with an exposure of from 10 to 20 hours. 

 The liquid, which is sold in cylinders, can be drawn off into a 

 measuring container and poured into the evaporating pan of the 

 vault. Owing to its extreme volatility, it should not be drawn from 

 the cylinder until the fumigation chamber is ready for the charge. 



Ethylene oxide gas is not injurious to fumigated commodities, 

 and no obnoxious odor or poisonous residue is left upon them. The 

 gas is not highly toxic to man and can be handled in small quan- 

 tities without danger or discomfort. Nevertheless, the operator 

 should avoid breathing the fumes for any length of time and should 

 not enter a heavy concentration without wearing a gas mask. 



If ethylene oxide is used alone, it is advisable not to operate an 

 electric fan inside the vault, lest an inflammable concentration of 

 the gas has been accidentally obtained. 



Ethylene oxide can be purchased in cylinders containing &y 2 , 18%, 

 75, or 195 pounds, at prices ranging from 50 cents to $2 per pound, 

 according to the quantity purchased and size of cylinders, f. o. b. 

 factory, east of the Kocky Mountains; for deliveries from the Los 

 Angeles and San Francisco warehouses prices are 5 cents per pound 

 higher. 



BIN FUMIGATION 



Bins used for the storage of foodstuffs, yarn, hosiery, etc., fre- 

 quently need to be fumigated. For this purpose any of the heavier- 

 than-air gases, such as carbon disulphide, chloropicrin, ethylene 

 oxide, or ethylene dichloride-carbon tetrachloride mixture, can be 

 used, provided it is suitable for treating the commodity stored in 

 the bin. 



The fumigant should be sprinkled evenly over the surface of the 

 contents of the bin, and the bin should then be covered as tightly 

 as possible. As the fumigant evaporates, the vapor, being heavier 

 than air, gradually penetrates the material from the top to the 

 bottom. 



The quantity of fumigant needed will depend upon the tightness 

 of construction of the bin, the type of material to be fumigated, and 

 the fumigant being used. Bins are seldom so tight as fumigation 

 vaults; hence larger dosages are necessary. 



