developing and introducing the first fiberglass fire helmet in 1947, the first NFPA-approved thermoplastic fire helmet in 1983, and the first ratchet headband used in a fire helmet in 1986.
This year marks the 100th anniversary of the invention of the hard hat by San Francisco–based mining-equipment-manufacturer E.W. Bullard, who first patented his “hard-boiled hat” in 1919. A forerunner of today’s safety helmet, Bullard’s hat was made from steamed canvas, glue, and wa...
It is another object of the present invention to provide a protective helmet in which the construction and orientation of the straps lessens the likelihood that the straps will be pulled free of the keys as a result of the force of an impact to the shell. ...
springs and the like and further permits the exertion of a substantial axial force for biasing the discs into face-to-face contact. The relatively large force enables the construction of the disc with relatively small, generally spherical detents having a diameter of as little as about 1/16 of...