February 1, 1916.] 



THE INDIA RUBBER WORLD 



Fire Hazards in Rubber Mills. 



IX the matter of fire hazards, every industry has its own in- 

 dividual peculiarities. The manufacture of rubber goods is 

 no exception. Besides the possibilities which are common 

 to any and every manufacturing establishment of similar build 

 and of equal size this industry is subject to some special risks, 

 and therefore the study of the causes of fires is an important one, 

 and the better known they are, the more satisfactorily can they be 

 guarded against, or more quickly extinguished when they occur. 



Very thorough and exhaustive researches have been made by 

 insurance adjusters, as well as by chemical experts, as to the 

 principal causes of fires in rubber factories. The result of these 

 studies seems to show that outside of those causes common to 

 all factories, the principal dangers peculiar to rubber manu- 

 facture come from the inflammability of the solvents used in the 

 industry, from spontaneous combustion of some of the materials, 

 and from excessive heat in some of the operations. The two 

 latter, however, are but minor hazards : practically the all- 

 important one is 

 in the use and ^ ffig 

 storage of naph- 

 tha and similar 

 solvents, and the 

 preparations in- 

 to which these 

 enter. 



A c a r e f 

 and comprehen- 

 sive study of all 

 the processes in 

 the manufacture 

 of rubber, made 

 by Charles E. 

 Macomber, Jr., 

 of the X. F. P. 

 A., has led him 

 to the following 

 conclusions a s 

 regards rubber 

 footwear fac- 

 tories : 



There is no fire hazard in crude rubber, nor in the process of 

 washing. In drying, he recommends that if the ordinary system 

 of steam coils is used, care should be taken that the pipes are 

 properly installed, resting on iron, bushed where they pass 

 through wooden partitions or floors, and protected by screens, 

 so there will be no danger of stock coming in contact with them. 

 Should a system be in use requiring a fan, additional precautions 

 should be taken. 



In the vacuum system of drying there would seem to be no 

 more hazard than there would be in the installation of a steam 

 pump or similar piece of apparatus. 



In the mixing rooms there is no material hazard, as the tem- 

 peratures of the material in process of compounding cannot be 

 carried high, on account of the possibility of spoiling from this 

 cause. 



The storage of the various ingredients may constitute a haz- 

 ard, however. As a rule these materials are stored in the com- 

 pounding room only in suflicient amounts for immediate use, the 

 bulk being kept in original packages, which are stored in a ware- 

 house or portion of the factory reserved for that purpose. 

 .'\mong the materials which may cause trouble, this investigator 

 mentions lampblack, which, he says, should be kept dry and 

 stored in small quantities, preferably in metal containers with 

 tightly fitting metal covers, for there are cases when, under cer- 



The 



ippe 



tain conditions, it has been known to heat and ignite spontaneously. 

 While sulphur is always found, it in itself presents no special 

 hazard, except that its presence would add fuel with the evolu- 

 tion of objectionable gases. There are also stored various oils, 

 resins, waxes and the like, but with proper care these should 

 give no trouble. In fact, this is true of all the material used in 

 the compounding of rubber. He considers that there are no 

 special hazards in calendering, frictioning or impregnating, as 

 the degree of heat is low, owing to the danger of spoiling the 

 compound. 



In the making, however, comes the hazard of the use of rubber 

 cement, and to this one preparation is laid the blame for the 

 vast majority of fires in rubber mills. The hazard both of the 

 manufacture and use of this article is due to the solvent used to 

 get the rubber in solution. This is naphtha. The kind generally 

 used and most preferred is that having a specific gravity of .706, 

 70 decrees Baume, bnilimj at 180 degrees F. and flashing and burn- 

 ing at ordinary 

 temperature. 



It is recom- 

 mended that the 

 manufacture of 

 cement should 

 always be con- 

 ducted in a de- 

 t a c h e d build- 

 ing away from 

 the main plant, 

 well ventilated, 

 and carried on 

 without the aid 

 of artificial light. 

 If light be neces- 

 sary, incandes- 

 cent light should 

 be used, the sock- 

 ets to be keyless, 

 the wiring run 

 in conduit, the 

 lamps enclosed 

 iiitches and fuses located outside 

 should be stored in an under- 

 more distant from any building, 

 ment mixing room. 



FEB. MAR. APR MAY JUNE JULY AUG btPT OCT NOV 



Distribution of Rubber F.vctory Fires Reported for Se\-en Ye.\rs. 



y average mean of dew points at 8 a. ' ' "^ 



DEC. 



. _ „ . veil daytime conditions or "working hours'' in southern New England. 



The second curve is the aggregate number of rubber fires reported in twelve factories, distributed by 

 nonths, in the same seven years. 



The lowest curve shows the aggregate number of rubber spreader fires reported i 

 iistributed by months during the same period. 





in vaporproof globes, and the 

 of the building. The naphth; 

 ground tank located 30 feet o: 

 and pumped as needed to the • 



Power for churns (these are best of the enclosed type) should 

 be furnished from outside by means of shaft or some kind of a 

 drive permitting a cut-ofif opening. While the speed of the churns 

 is necessarily slow (owing to the ease with which rubber is elec- 

 trified by friction and pressure), as a precautionary measure it 

 would seem advisable to "ground" all of the machinery. 



The cement, except that in immediate use, should be stored 

 in tightly covered metal cans. There are cans on the market 

 designed for this purpose. 



If the plant be sprinklered the cement house should contain a 

 standard sjstem of automatic sprinklers, and in all cases the 

 cement room should be provided with a steam jet of ample size 

 for smothering fire, having an easily accessible valve located on 

 the outside of the building. 



A day's supply only should be brought into the factory, and 

 only enough distributed to the operators for immediate use. At 

 the close of the day that remaining in the small pans should be 

 returned to the container, which should be removed to the cement 

 house. 



In some factories naphtha is used for thinning the cement at 



