Page 48 - OHS, March 2021

PPE: HEAD & FACE PROTECTION
From the Hard Hat to the Helmet
Innovations in technology have led to the industry shift from hard hats to helmets.
BY SAMANTHA HEIM
Over the past several years, hard hats received a small yet significant change: rated chinstraps. Now, more than ever,
manufacturers are producing climbing- style helmets with a rated chinstrap. What are the histories of the hard hat and what could the future bring?
History Lesson
Nearly 100 years ago when he came back from World War I, Edward Bullard noted the rapid increase in city infrastructure. Men moving and working at height were wearing minimal to zero PPE. The Bullard company, originally a mining equipment manufacturer, had already made a less- than-durable mining cap constructed from leather.1
Inspired by metal helmets worn by soldiers in the war, Edward Bullard made the first patented hard hat, aptly named the hard-boiled hat. He used steamed canvas, black paint and shellac to create the hat. Later, an inner suspension was added to absorb the force of objects hitting the helmet. Head protection soon became a suggestion, then a requirement. In 1931, the Hoover Dam project was the first time an employer purchased and mandated the use of hard hats for employees. The iconic Golden Gate Bridge project followed suit.2 Over the years, as hard hats were required on more projects, manufacturers worked to find durable, quality and long-lasting materials.
Material Matters
In the 1930s, manufacturers started making hard hats from aluminum, which is still done today. However, aluminum is an electrical conductor and not a suitable option for some worksites.3 By the early 1940s, hard hats transitioned to fiberglass, then a decade later there was a transition to thermoplastics, which is still used today.4 Gone are the hard hats made from steamed canvas and glue. Since the early 2000s, the majority of hard hats are made from plastic. The most common plastics are ABS (acrylonitrile butadiene styrene), PE (polyethylene) and PC (polycarbonates). Kask, an
Italian equipment manufacturer, uses PP (polypropylene) and PS (polystyrene).
“The helmet manufacturing process for the three materials will be the same,” says Michael Creighton, an Engineering Manager at prototype and product design firm Creative Mechanisms. “The PE is the lowest cost raw material but can still offer good protection. PC will have the highest amount of strength, impact resistance and temperature exposure, but it is also the most expensive of the three. ABS will basically fall in the middle.”
Regardless of the plastic type used, hard hats must pass specific tests to meet OSHA regulations.
There’s a New Standard in Town
Before OSHA was created in 1970, PPE requirements were enforced by construction companies. Now, standards organizations like ANSI have outlined specific helmet regulations.5 The ANSI/ ISEA Z89.1 covers performance and testing requirements, as well as different types and classifications of hard hats. The basic requirements for head protection are the following:
■ Resist penetration by either falling or stationary objects
■ Absorb shock caused by a blow to the head
■ Be water-resistant and slow to burn
Manufacturers are required to identify if a hard hat is Type I, for top impact or Type II, for top and lateral impact. The class also must be identified as one of the following classes:
■ Class G (General) is rated for protection against 2,200 volts
■ Class E (Electrical) is rated for protection against 20,000 volts
■ Class C (Conductive) offers no electrical protection.
It is important to make sure the hard hats you select meet the ANSI Z89.1 standard. Lower profile “bump caps” look similar to hard hats, but not all are ANSI certified.
Personalization and Comfort
Companies like 3M, Honeywell and MSA are expanding the comfort and adaptability of the traditional hard hat. Two popular styles are the cap style and full brim style. Some hard hats can accommodate
44 Occupational Health & Safety | MARCH 2021
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