During the construction of Hoover Dam many workers were killed by falling rocks or debris.To protect themselves they made an early version of hard hats. What did they call them back them?
Some high scalers took cloth hats and dipped them in tar, and allowed them to harden. When workers wearing such head gear were struck hard enough to inflict injuries such as broken jaws, they did not sustain any skull damage. Six Companies ordered thousands of what initially were called “hard boiled hats” (later called “hard hats”) and the use of them was strongly encouraged.
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