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Methyl Bromide is a colorless, odorife ss gas available in pressurized cans or 

 cylinders* It is toxic to all forms of animal life, and it has a delayed effect 

 on humans, EXTRHiE CAUTION is necessary in its usee Equipment for gassing with 

 Methyl Bromide includes a suitable applicator, a gas mask with proper organic 

 vapor canisters, and a Methyl Bromide detector. Gassing can be accomplished from 

 outside the room by using an applicator coupled with a copper tubing running through 

 the storage wall. The tubing opening should be directly in front of a blovrer or 

 auxiliary fan and circulating fans should be operating throughout the gassing period 

 in order to assure uniform gas distribution, Ifethyl Bromide is applied at the rate 

 of onequarter of a poui^ per 1,000 cubic feet of free air space. No injury to 

 apples has been observed at this dosage in storages of normal temperatures (32- 

 36°F,) and atmospheres. This gas concentration is maintained for five hours, 

 follovired by a complete air change by ventilation. 



In order to insure proper ventilation, cross air currents from side-to-side 

 or end-to-end are necessary. Forced draft by fans is desirable. Storage rooms 

 which cannot be completely ventilated in about two hours sho\ild not be gassed with 

 this material. Final check for the presence of Methyl Bromide must be made by an 

 operator equipped with a gas mask and the special detector apparatus. 



Carbon Dioxide is a natural product of respiration of both apples and humans 

 and is not poisonous in the same sense as Mettiyl Bromide gas. However, in an 

 atmosphere of high carbon dioxide concentration there remains little room for the 

 oxygen necessary for the life of mamraals, so that suffocation occurs. Gassing 

 with Carbon Dixoide still requires CA UTION , as an error could prove fatal to hymans- 

 «as well as to intended rodent victims'^ There is no chance of injury to the apples 

 by the gas itself but efficient circulation near the scurce of Carbon lioxide is a 

 requirement to prevent localized freesingc Carbon Dioxide is applied in the form 

 of "Dry ice", which is a solid at 110°Fo below zero. 



The storage room must be sealed tightly, as with Methyl Bromide » Fans, of 

 household type or larger, should be placed so as to circulate air over each area 

 where the dry ice is to be placed. Fifty-pound blocks of dry ice are placed in the 

 storage passagev/ays , These blocks should be handled only with ice tongs or very 

 heavy gloves. Each block can be broken up into smaller pieces, with a heavy hammer, 

 just prior to sealing. Proper carbon dioxide concentration (20JS) is secured at the 

 rate of 25-30 pounds of dry ice per 1,000 cubic feet. This concentration is main- 

 tained for about six hours. As with Methyl Bromide, complete ventilation is required 

 before operators can enter the storage. But, unlike Methyl Bromide, it is not 

 necessary that the Carbon Dioxide be evacuated immediately, 



l/ Data on Methyl Bromide taken from literature prepared tiy Frank ViT. Southwick 

 Research Professor of Pomology, Univ, of Massachusetts, Amherst, Mass, 



Zf Data on Carbon Dioxide taken from literature prepared ty Messrs, S, A, Pieniaaek 

 and Everett P, Christopher, IMiv, of Rhode Island, Kingston, R,I, 



— • W, R, Jones 

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