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Hard hat
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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. Inside the helmet is a suspension that spreads the helmet's weight over the top of the head. It also provides a 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.
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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. Inside the helmet is a suspension that spreads the helmet's weight over the top of the head. It also provides a 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. Sometimes the helmet shell has a midline ridge.
They 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 They were originally made from metal, then fiberglass, but from the 1950s rigid plastic has been the most common material.
Some contemporary cap-style hard hats feature a rolled edge that acts like a rain gutter to channel rainwater to the front, allowing it to drain off the bill, instead of letting the water run down the wearer's neck.
A hard hat issued by a firm often has that firm's name or some word or logo on its front.
Hardhats may also be fitted with:
Blue-collar workers engaged in occupations that require protective equipment are sometimes called "hard hats".
Hard hat colors can signify different roles on construction sites. For instance, white might signify supervisors or engineers, blue technical advisors, red safety inspectors, and yellow laborers.
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 maintained, it should be replaced after five years of use.
In 1997, the American National Standards Institute revised its performance standards for hard hats. Conformity to these standards and regulation are not necessary but almost all manufactures comply:
- ANSI Type I / CSA Type 1 hard hats meet stringent vertical impact and penetration requirements.
- ANSI Type II / CSA Type 2 hard hats meet both vertical and lateral impact and penetration requirements and have a foam inner liner of expanded polystyrene (EPS).
- A Class E hard hat has been proof-tested to insulate up to 20,000 volts of electrical potential.
- ANSI have compliance for hard hats and their combustibility or flammability criteria.
A bump cap is a lightweight kind of hard hat with simplified suspension or padding in lieu of suspension and having only a chin strap. It is used where there is a possibility of scraping or bumping one's head on equipment or structure projections, but is not strong enough to absorb large impacts, such as from a tool dropped several stories.
History
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.
In the United States, the was a mining equipment firm in California, created by Edward Dickinson Bullard in 1898, who was in the industrial safety business for 20 years. The company sold protective hats, but they were only made of leather. His son, E.W. 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", made of steamed canvas, glue and black paint. That same year the U.S. 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 that would provide a more effective hat. These early designs bore a resemblance to the military M1917 "Brodie" helmet, which served as their inspiration.
In 1933 construction began on the Golden Gate Bridge in San Francisco California. This was the first construction site in history where construction workers were required to wear hard hats, by order of Joseph Strauss, the project chief engineer. He wanted the workplace to be as safe as possible; hence, he installed safety nets and required hard hats while on the job site. Strauss also asked Bullard to create a hard hat to protect workers who performed sandblasting. Bullard produced a design that covered the worker's face, provided a window for vision and a supply of fresh air via a hose connected to the air compressor.
aluminum became a standard for hard hats around 1938, except in electrical applications.
Fiberglass came into use in the 1940s.
Thermoplastics took over in the 1950s, because they were easy to mold and shape with heat and cost less to manufacture. Today, most hard hats are made from high-density polyethylene (HDPE) or advanced engineering resins, such as Ultem.
Brown fiberglass hard hats are 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, earmuffs, and perspiration-absorbing cloths which line the hats. Today, attachments include radios, walkietalkies, pagers, and cameras.
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