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CIRCULAR 8 6 9. U. S. DEPARTMENT OF AGRICULTURE 



Figure 17. — Door of a tobacco warehouse sealed by spraying with a vinylite plastic. 



The chamber may be piped in the same way as warehouses. If 

 hydrogen cyanide is to be used, the inlet of the piping system should 

 be in a small room attached to the chamber. The room need be only 

 about 3 feel square — jusl large enough to hold a platform scales on 

 which rests the cylinder of fumigant. From the top of this room 

 should extend a vent pipe connected to an electric fan. The fan 

 should be operated when gas is introduced into the chamber, so that 

 any leakage is drawn up and away from the operator. The fumiga- 



