8 



CIRCULAR 369, U. S. DEPT. OF AGRICULTURE 



Machinery that is used to pack, mix, or handle foodstuffs in any 

 way should be opened as completely as possible and all accumulations 

 of materials removed. Most fumigants do not penetrate for more 



Figure 10. — Doorway between compartments in modern concrete storage warehouse sealed 

 for fumigation. Framework of 2- by 4-inch lumber, covered with heavy fiber-reinforced 

 waterproof paper, forced against strips of heavy felt padding. The fireproof doors 

 have been rolled back. Note the small door, which also shuts against felt gaskets, for 

 the use of fumigators. A glass window has proved useful in permitting inspection of 

 operations. 



Figure 11. — Opening to elevator shaft sealed ready for fumigation in same manner as the 

 doorway in figure 10. In both cases the sealing was done at the Naval Supply Depot, 

 Naval Operating Base, Hampton Roads, Norfolk, Va. 



than a few inches into flour, meal, or similar foodstuffs; hence, such 

 accumulations, if left in the machinery, protect insects from the 

 effects of the gas. Accumulations of waste material under or around 



