Cause for Fire Hose Failure
Chief George B. Goff, of the Oklahoma City, Okla., Fire Department has been much concerned over the rapid deterioration of its fire hose which seemed to burn out back of each coupling as though from an acid. This trouble has been experienced the last few years although the couplings and rings are of much better material than formerly. In order to learn the cause for these burns, Chief Goff had the City Chemist make a number of tests. The following report was submitted by C. E. Clifford, City Chemist, after the tests had been completed:
“In my opinion the cause of the deterioration of this hose is due to the puncturing: of the inner lining: of rubber by the copper collar. When this rubber lining: is punctured, water seeps into the fabric and creates a voltaic cell which generates a constant and a readily detectable quantity of electric current.
“When the threaded hose connection and the inner collar are submerged in the city water an electric current of one* seventh volt is generated immediately. In my judgment, this quantity of electrical current generated would be increased in direct proportion to the time that these two parts were submerged in our city water, and would be continuously increased on account of the increase of the metallic salts which would be formed under this condition. Therefore, the longer the hose connections remain moist and the fabric saturated with water, the more rapldlv the fabric would be deteriorated by an increase of the metallic and sulphate ions In the water.
“There is enough difference in the composition of the two pieces of metal to form a positive and a negative plate, and it would appear to me that the difference is a definite error m the manufacture of the hose connection, and in order to correct it. the collar and the outside connection should be made of the same composition.