A hard hat is a type of helmet predominantly used in workplace environments, such as construction sites, to protect the head from injury by falling objects, debris, bad weather, and electric shock. Sometimes the helmet shell has a midline ridge. Inside the helmet is a suspension which spreads the helmet's weight over the top of the head, providing spacing between the helmet's shell and the head so that if an object strikes the head, a safety distance cushion of approximately 3cm lessens the blow.
collarless">http://www.himfr.com/buy-collarless_shirts/">collarless shirtsThey are typically required personal protective equipment where heavy labor is being performed. They were originally made from metal, then fiberglass, but from the 1950s rigid plastic has been the most common material.
Its lower edge sometimes has a small gutter to catch rainwater and shed it off the front peak; but that needs the lower edge of the helmet to be horizontal instead of coming further down the back of the head.
Blue-collar workers who engage in heavy professions that require protective equipment are sometimes called "hard hats".
On construction sites hard hat colors can signify different roles. For instance: white for supervisors, blue for technical advisors, red for safety inspectors, and yellow for workmen.
A hard hat also gives a worker a distinctive profile, identifiable even in peripheral vision, for safety around equipment or traffic. Safety colors like orange or green do not appear in peripheral vision, but the hard hatted shape of a worker will be avoided.
Even if a hard hat is properly inspected and cared for, it should be replaced after five years of use.
Management professor Peter Drucker credits writer Franz Kafka with developing the first civilian hard hat when he was employed at the Worker's Accident Insurance Institute for the Kingdom of Bohemia (1912), but this is not supported by any document from his employer.[1]
In the USA, the E.D. Bullard Company was a mining-equipment firm in California created by Edward Bullard father who was in the industrial safety business for 20 years. His father sold protective hats but they were only made of leather. Edward Bullard, arrived home from World War I with a steel helmet, which provided him with an idea to improve industrial safety. In 1919 Bullard patented a "hard-boiled hat", created through steaming canvas with resin, gluing several layers together which provided that hard molded shape. Within the same year the US Navy commissioned Bullard to create a shipyard protective cap, which began the widespread use of hard hats. Not long after, Bullard developed an internal suspension which would provide a more effective hat.
In 1933 construction began on the Golden Gate Bridge in San Francisco California.[2] This was the first construction site in history which required all employees to wear hard hats, by command of the project chief engineer, Joseph Strauss. He wanted the workplace to be as safe as possible; hence, he placed safety nets and required hard hats while on the job site. Strauss also asked Bullard to create a hard hat to protect workers who do sandblasting. Bullard came up with a design covering the worker's face with a vision window and a pump to bring fresh air into the mask.
Around 1938 aluminium became a standard for hard hats except in electrical applications.
In the 1940s fiberglass came into use.
Around ten years later thermoplastics took over because they were easy to mold and shape with applied heat. Today most hard hats are made from high-density polyethylene (HDPE).
Brown fiberglass is still preferred by workers who buy their own equipment, for better balance, lighter weight, resistance to scrapes and stains, and shedding rain without big drops forming on the edge. These hats stay on when tilting the head at an extreme angle.
In 1997 ANSI allowed the development of a ventilated hard hat to keep wearers cooler. To it could be added accessories like face shields, sun visors, ear muffs, and perspiration-absorbing cloths which line the hats. Today, attachments include radios, walkietalkies, pagers, and cameras.
For nearly sixty years, aluminum hard hats were popular and had almost a cult-like following but were phased out about 1997 when new regulations required stricter safety standards. There were about a half dozen companies producing a version of the aluminum hat throughout that time. Nearly a decade later, new full brim and cap-style aluminum hard hats were introduced by Skull Bucket. They are easily recognizable due to a re-inforced crown secured by eight rivets. They are constructed of space-age aluminum alloy and are ANSI safety compliant. Aluminum hard hats are used almost exclusively by oil well fire fighters due to the extreme heat they encounter. The forestry industry and loggers favor the aluminum version as well, many wearers remembering the solid, reliable McDonald-T hard hats that were so popular for years. Other industries using the aluminum hard hat are rock quarries, heavy machine operation, oil production, mining, bridge construction and maintenance, water well drilling and pipelines, and construction. The aluminum hats are restricted from use wherever electrical hazards exist. To our knowledge, Skull Bucket is the only company currently manufacturing aluminum hard hats.
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