Construction of Warehouses 



In the foregoing comparisons consideration must be given to the type of build- 

 ing to be sealed. In the first instance at Wilmington, the warehouse is an old-type, 

 brick-wall, heavy mill-construction building with two floors divided into four 

 sections each. 



The storage units at Newport News are modern reinforced-concrete and steel- 

 type buildings. The doors, windows, and ventilators are so constructed that 

 very little sealing is necessary to place them in fumigable condition. It is believed 

 that, in this instance, even with the limited amount of work necessary, plastic 

 could have been applied in a shorter time. 



At Norfolk, Va., the warehouses have brick fire walls and are built of rein- 

 forced concrete, with some stucco included. In the construction of roofs and 

 sheds, wood and composition roofing material are used. These warehouses are 

 not in good condition from a construction standpoint because of wartime 

 operation. 



Warehouses at North Charleston, S. C, are largely constructed of hollow tile, 

 with wood and composition roofing and sheds. Less sealing was required on 

 these buildings and the Navy equipment, used for sealing work, was of the more 

 efficient type. It is to be recognized, in this instance, that the situation is not 

 comparable with any of the other examples; however, the extremely limited 

 amount of labor required illustrates the efficiency of plastic application. 



Cost of Plastic Materials 



Established costs, based on square-footage application of plastic coating per 

 gallon, are not applicable to an analysis of this kind. Very little sealing in a 

 tobacco warehouse can be figured on a square-footage basis. 



At the time the experimental work was performed by the Department, the cost 

 of plastic material was approximately $3 per gallon in 50-gallon drums, f. o. b. 

 factory, with a slight quantity discount allowed. Webbing agent was quoted at 

 approximately $3.75 per gallon in 50-gallon drums, with sealing compound at 

 approximately $7.25 on the same basis. Pigment, used in much smaller quan- 

 tities, would not affect materially the over-all cost of this material when added to 

 the bulk price. These prices were used in calculating the cost of the various 

 plastic-sealing operations mentioned in this publication. They are based on mini- 

 mum quantities of material, and it is recognized that quantity purchasing will 

 effect further reduction in the cost of plastic sealing as compared with that of 

 other methods. It is also believed that with the more extensive use of plastic 

 for sealing, a further reduction can be effected in the cost of these compounds. 



SAFETY 



Limited Fire Hazard 



Vinylite plastic, when dry, is not a fire hazard. It will burn when in contact 

 with flame but does not carry it readily. The solvents used, however, are highly 

 inflammable, methyl ethyl ketone having a flash point of 19 ° F. or — 7 C, and 

 acetone a flash point of — 4 F. or — 20 C. Acetone, despite its lower flash point, 

 is being used more extensively as a solvent at this time. It is a less expensive 

 ingredient and is equally as satisfactory. As these solvents are highly volatile 

 and dissipate rapidly, there is danger at any time when a concentration of fumes 

 occurs during actual application. 



When adequate precautions are taken it is not likely that a serious fire hazard 

 will develop in tobacco warehouses by the use of plastic materials. However, it 



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