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 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.
Blue-collar workers, especially union shop construction workers engaged in
occupations that require protective equipment are sometimes referred to as
"hard hats". A bump cap is a lightweight hard hat
using a simplified suspension or padding and a chin strap. Bump caps are used
where there is a possibility of scraping or bumping one's head on equipment or
structure projections, but are not sufficient to absorb large impacts, such
as that from a tool dropped from several stories.
History In the early years of the ship building
industry, workers covered their hats with pitch, and set them in the sun to
cure, a common practice for dock workers in constant danger of being hit on the
head by objects dropped from ship decks. Management professor Peter Drucker
credited writer Franz Kafka with developing the first civilian hard hat
while employed at the Worker's Accident Insurance Institute for the Kingdom of
Bohemia, but this information is not supported by any document from his
employer. In the United States, the E.D. Bullard
Company was a mining equipment firm in California created by Edward Dickinson
Bullard in 1898, a veteran of the industrial safety business for 20 years.
The company sold protective hats made of leather. His son, E. W. Bullard,
returned home from World War I with a steel helmet that provided him with
ideas 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 that began the
widespread use of hard hats. Not long after, Bullard developed an internal
suspension to provide a more effective hat. These early designs bore a
resemblance to the military M1917 "Brodie" helmet that served as their
inspiration. On the Hoover Dam project in 1931, hard
hat use was mandated by Six Companies, Inc. In 1933, construction began on the
Golden Gate Bridge in San Francisco California. Construction workers were
required to wear hard hats, by order of Joseph Strauss, project chief engineer.
Strauss strove to create a safe workplace; hence, he installed safety
nets and required hard hats to be worn 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 an air
compressor. In those times many workmen's safety helmets were made of
steel. Aluminum became a standard for hard hats
around 1938, except for electrical applications. MSA introduced the new
plastic Skullgard® Helmet in 1930 for the metals industry to withstand radiant
heat loads of up to 350 °F. New plastic Bakelite was used to provide protection
rigid enough to withstand hard sudden impacts within a high-heat environment
but still be light enough for practical use. Machinery of the times required
that helmet materials used be electrically non-conducting. Bakelite
resin compounded with wire screen and linen. The Skullgard Helmet is still
manufactured. MSA also produced a low-crown version for coal miners known
as Comfo-Cap® Headgear. Coal miners were quick to take up MSA’s low-crown version
of the headwear called Comfo-Caps. Fiberglass came into use in the 1940s.
Thermoplastics took over in the 1950s, as they are easy to mold and shape with
heat and cost less to manufacture. Today, most hard hats are made from
high-density polyethylene or advanced engineering resins, such as Ultem. In
1952, MSA offered the Shockgard Helmet to protect electrical linemen from
electrical shock of up to 10,000 volts. In 1961, MSA released the Topgard®
Helmet, the first polycarbonate hard hat. 1962 brought the V-Gard® Helmet
that today is the most widely used hardhat in the United States.
In 1997 ANSI allowed the development of a ventilated hard hat to keep wearers
cooler. Accessories such as face shields, sun visors, earmuffs, and
perspiration-absorbing lining cloths could also be used; today, attachments
include radios, walkie-talkies, pagers, and cameras.
Another milestone was reached in 2013 with production of the MSA V-Gard GREEN
Helmet, the first industrial safety product produced from nearly 100 percent
renewable resources. High-density polyethylene construction sourced
entirely from sugarcane ethanol is recyclable, reducing the carbon
footprint associated with this product type.
Design Because hard hats are intended to
protect the wearer's head from impacts, hats are made from durable materials,
originally from metal, then fiberglass, and most-commonly rigid plastic.
Some contemporary cap-style hard hats feature a rolled edge that acts as a
rain gutter to channel rainwater to the front, allowing water to drain off the
bill, instead of running down the wearer's neck. A cowboy hard hat is a
hard hat resembling a wide brimmed cowboy hat, although some organizations
disallow their use. Organizations issuing hard hats often
include their names and/or logos on the front of each hard hat.
= Accessories = Hard hats may also be fitted with:
A visor: As in a welding helmet, or
A safety visor. An extra-wide brim attachment for
additional shade. Ear protectors.
Mirrors for increased rear field-of-view.
A small device that is used to mount a headlamp or flashlight to a hard hat.
The mounting device frees hands to continue working rather than having to
hold a flashlight. A chinstrap to keep the helmet from
falling off if the wearer leans over. Thick insulating side pads to keep sides
of the head warm. Examples are seen in Ice Road Truckers.
= Colors and identification = Hard hat colors can signify different
roles on construction sites. These color designations vary from company to
company and work site to work site. Government agencies such as the U.S.
Navy and DOT have their own hard hat color scheme that may apply to
subcontractors. On very large projects involving a number of companies,
employees of the same company may wear the same color hat.
The most common color scheme is white for managers, engineers, foremen or
supervisors. Other hard hat styles may be required for a job; brown fiberglass
hard hats are worn by welders and other workers for high heat applications.
Green often signifies a safety inspector, but is also occasionally used
for new workers. General laborers and earth-moving operators often wear
yellow. Carpenters, technical advisers and temps may wear blue. Orange is
sometimes used for road crews, new employees or visitors. Some companies
offer loaner hard hats in pink for workers who forget their own hard hat.
At one time, blasters traditionally wore red.
= Stickers = Supervisors often are not familiar with
all workers on a construction site. Often, stickers, labels and markers are
used to mark hard hats so that important information can be shared. Paint or
permanent markers can degrade the plastic in hard hats; instead, labels or
masking tape are often applied to a hard hat with the worker's name written on
it. Stickers with company logos are very common. Stickers that indicate a
worker's training or qualifications are also very common; many companies provide
ready-made stickers to indicate that a worker has been trained in electrical
safety, confined space safety, excavation trench safety, or operation
of specialized equipment. Environmental monitors often make stickers to indicate
that the worker has been educated on the risk of unexploded ordnance or the
archaeological/biological sensitivity of a given area. Stickers may indicate who
is authorized to be present on site. Unions may offering free stickers for
hard hats and other objects. A hard hat also provides workers with a
distinctive profile, readily identifiable even in peripheral vision,
for safety around equipment or traffic. Peripheral vision registers shapes but
not colors; the obvious shape of a hard hat is therefore easier for machine
operators to recognize and avoid. Some companies also require reflective tape
to be applied to hard hats to increase visibility of workers at night.
Standards In 1997, the American National Standards
Institute revised its performance Z89.1 standards for hard hats that has been
harmonized with CSA Z94.1 standard. Conformity to these standards is not
mandatory but most manufacturers comply. Each hard hat is specified by both Type
and Class: Types: 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 made of expanded
polystyrene. Classes:
Class E provides dielectric protection up to 20,000 volts.
Class G provides dielectric protection up to 2,200 volts.
Class C provides no dielectric protection.
A hard hat is specified by both Type and Class; for example: Type I Class G.
ANSI standards for hard hats set combustibility or flammability criteria.
ANSI Z89 standard was significantly revised in 1986, 1997 and 2003. The
current American standard for hard hats is ISEA Z89.1-2009, by the International
Safety Equipment Association that took over publication of the Z89 standard
from ANSI. The ISO standard for industrial protective headgear is ISO
3873, first published in 1977. In the UK, the Personal Protective
Equipment Regulations 1992 specifies that hard hats are a component of PPE
and, by law, all those working on construction sites or within hazardous
environments are required to wear hard hats.
In Europe all hard hats must have a manufacturer set lifespan, this can be
determined from the expiry date or a set period from the manufacture date, which
is either stuck to the inside or embossed in the hard hat's material.
Examples See also
Goggles Protective clothing
Safety engineering Steel-toe boots
References