Mine Stench

Last week while mine inspectors were investigating the coal mine tragedy in Millfield, Ohio (see p. 18), Daniel Harrington, Chief of the Safety Division of the U. S. Bureau of Mines, urged metal mine operators to adopt a modern method of warning miners of danger. The alarm signal is a penetrating odor. Metal mines (unlike coal mines, which use electrically operated fans) are ventilated by compressed air which travels into the farthest corners at the rate of about 1,000 ft. per sec. Engineers have found that a little odorous liquid injected at the source of the air supply will cause the odor to be carried throughout the largest mine in a few minutes.

The system commonly used today of flashing electric lights as a danger warning is not wholly successful. Busy miners often fail to notice the signals at once. Often an electric system will be disrupted by the very accident that occasions its use. The odor method is cheap, sure. Even the busiest miner will notice an unusually unpleasant smell.

Experimental work was carried on in 1918 by the Bureau of Mines at Granite Mountain Shaft, Butte, Mont., where 13 years ago 162 men lost their lives in a fire because warning was not spread quickly enough. At first pleasant odors were used but were not successful. Workmen did not run when they .sniffed violets or roses. But when experimenters released butyl mercaptan which smells like garlic, miners dropped their tools at once, raced for the exit. The stench safety method has been adopted by the American Standards Association which suggests to mine operators how best to conserve their employes’ lives. Although the U.S. Bureau of Mines cannot force operators to obey American Standards, most important operators follow their recommendations. Most up-to-date mines in Montana, Arizona, California, Michigan and Minnesota are equipped to use the stench warning method.