Hard hat

Construction worker at Douglas Dam, Tennessee (TVA), 1942

Workmen wearing hard hats at the site of a Texas oil well in 1940.

A hard hat is a type of helmet predominantly used in workplace environments such as industrial or construction sites to protect the head from injury due to falling objects, impact with other objects, debris, rain, and electric shock. Suspension bands inside the helmet spreads the helmet's weight and the force of any impact over the top of the head. A suspension also provides space of approximately 30 mm (1.2 inch) between the helmet's shell and the wearer's head, so that if an object strikes the shell, the impact is less likely to be transmitted directly to the skull. Some helmet shells have a mid-line reinforcement ridge to improve impact resistance.

单词	Safety hat
释义	Safety hat 英语百科 Hard hat A hard hat is a type of helmet predominantly used in workplace environments such as industrial or construction sites to protect the head from injury due to falling objects, impact with other objects, debris, rain, and electric shock. Suspension bands inside the helmet spreads the helmet's weight and the force of any impact over the top of the head. A suspension also provides space of approximately 30 mm (1.2 inch) between the helmet's shell and the wearer's head, so that if an object strikes the shell, the impact is less likely to be transmitted directly to the skull. Some helmet shells have a mid-line reinforcement ridge to improve impact resistance.
随便看	Marconaflo slurry transport的意思 Marcona Mining Company的意思 marconi的意思 marconi aerial的意思 Marconian的意思 Marconi antenna的意思 Marconi beam aerial的意思 Marconi beam antenna的意思 Marconi coherer的意思 Marconi commutator的意思 Marconi detector的意思 marconigram的意思 marconigram的意思 marconigraph的意思 marconigraph的意思 marconigraph的意思 marconigraph的意思 marconigraphy的意思 Marconi, Guglielmo的意思 Marconi Instruments Limited的意思 Marconi magnetic detector的意思 marconi operator的意思 Marconi plc的意思 Marconi rig的意思 Marconirigged的意思

Safety hat

Hard hat