Construction helmet
Construction helmet
Modern helmets are constructed from plastics. Premium price helmets are made with fiberglass reinforced with Kevlar or carbon fiber. They generally have fabric and foam interiors for both comfort and protection. Motorcycle helmets are generally designed to distort in a crash (thus expending the energy otherwise destined for the wearer's skull), so they provide little protection at the site of their first impact, but continued protection over the remainder of the helmet.Helmets are constructed from an inner EPS “Expanded Polystyrene foam” and an outer shell to protect the EPS. The density and the thickness of the EPS is designed to cushion or crush on impact to help prevent head injuries. Some manufacturers even offer different densities to offer better protection. The outer shell can be made of plastics or fiber materials. Some of the plastics offer very good protection from penetration as in lexan (bulletproof glass) but will not crush on impact, so the outer shell will look undamaged but the inner EPS will be crushed. Fiberglass is less expensive than lexan but is heavy and very labor intensive. Fiberglass or fiber shells will crush on impact offering better protection. Some manufacturers will use Kevlar or carbon fiber to help reduce the amount of fiberglass but in the process it will make the helmet lighter and offer more protection from penetration but still crushing on impact. But this can be very expensive.
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