A fire helmet to a firefighter represents the tradition and spirit of the fire service. The helmet is a personal piece of equipment that tells a story about the firefighter who wears it. For centuries, firefighters have relied on their helmets to protect them through the toughest fire environments. Manufacturers of fire helmets have used advanced engineering techniques and innovative designs to improve the fire helmet to better protect firefighters from harm. Let’s take a look at the evolution of the fire helmet.
The Fire Helmet…Then and Now
In 1740, Jacobus Turk, a firefighter from New York City, invented the first leather fire cap to protect his firefighters from the intense heat from structural fires. His helmet was rounded with a narrow brim and although it was an innovative design it didn’t offer much protection from high heat or impact. In 1836, Henry T. Gratacap, a volunteer New York City firefighter, designed a more modern eight comb fire helmet. Most of today’s fire helmets are designed in this form with eight triangular sections coming from the brim and joining at an apex above the firefighters head.
At the turn of the century, aluminum fire helmets were introduced to the fire service. These helmets were designed to look just like the traditional leather helmets but were much less expensive to produce. Firefighters quickly realized that the aluminum helmets were not ideal for firefighting environments since aluminum not only conducts heat but also electricity. Manufacturers quickly abandoned the aluminum helmets and moved back to the leather style model.
Engineering technology advanced and by the late 1940s manufacturers were designing fire helmets using fiberglass materials. In 1979, the National Fire Protection Association (NFPA) developed standards for structural firefighter helmets. The standard required that fire helmets be tested for resistance to electrical current, penetration, impact and heat and flame resistance. With this new standard, manufacturers began exploring the use of more modern materials, such as fiberglass and thermoplastic.
These materials, unlike the aluminum, were durable and heat resistant and provided a high level of protection for firefighters. In 1983, the NFPA approved the first thermoplastic fire helmet for the fire service. Thermoplastic and fiberglass are two of the most popular materials, in addition to leather, used in fire helmets today. The leather helmet, also known as the “leatherhead,” is made mostly of all leather materials. This is the true traditional helmet that firefighters first embraced hundreds of years ago. Leather helmets are resistant to heat and provide firefighters with the look, feel and smell many prefer; however, leather is expensive, heavy and often requires longer lead times to produce because the helmets are all hand-sewn. Let’s look at the benefits and shortcomings of thermoplastic and fiberglass materials.
Thermoplastic and Fiberglass Materials
High performance thermoplastics offer superior impact protection, durability and heat resistance when used in fire helmets. Thermoplastic becomes softer and more malleable as it gets warmer and harder and more brittle at lower temperatures. These unique properties are helpful in a high-heat environment such as a fire. Today’s high-heat thermoplastics are designed to withstand short-term, repeated exposure to temperatures of 260º C (500º F). Enduring temperatures at 260ºC or higher may result in the thermoplastic material bubbling or blistering. When exposed to high heat for a prolonged period of time, plastic begins to absorb moisture. The plastic gets softer and will withstand impact; however, when the helmet cools off a bubbling or blistering can be seen. If this occurs in a fire helmet it is an indication that the helmet has seen too much heat and must be replaced. Although the helmet has blistered, thermoplastics are designed to continue to provide high impact protection after the surface has cooled.
When firefighters think of a traditional fire helmet, they most often think of leather or a composite (fiberglass) helmet. We’ve already addressed the concerns with leather being expensive and heavy and requiring longer lead times. The fiberglass helmets provide good protective properties; however, it’s important to understand how fiberglass performs in firefighting situations. Fiberglass is actually composed of two materials: a thermoset resin (essentially a glue) and glass fibers which can vary in length. Thermoset resins are a family of plastics that do not melt at high temperatures and are created by mixing two base materials. One of the ingredients is a catalyst that, when combined with the other agents during molding, will solidify, locking itself and the glass fibers into a rigid state. The strength of a thermoset composite material comes primarily from the fibers of glass or other materials that are bonded together by the resin. The real strength of the helmet comes from the resin.
The resin and the fibers in a fiberglass helmet are formulated to make a product that has a good balance between strength and weight. Fiberglass offers great resilience when exposed to chemical agents; however, the resin of a composite helmet will degrade with repeated exposure to extreme temperatures. Each exposure to high heat weakens the molecular structure of the resin. Lower temperatures will also degrade the resin but over a much longer period of time. Ultraviolet (UV) exposure from sunlight has a similar effect on these resins.
Fire Helmet Models
There are a variety of fire helmet models on the market today, but three specific designs are the most popular among firefighters: the traditional American helmet; the streamlined contemporary helmet; and the jet-style helmet.
The traditional helmet, which was first embraced hundreds of years ago, is designed with ribs protruding from the dome, created by the joining of eight triangular sections, with a long brim in the back of the helmet to allow water to drip off and often adorned with a customized shield in the front to identify the firefighter. The contemporary helmet is often a lower profile and lighter weight design than the traditional, offering more streamlined and simple lines. This style helmet allows for the face, eyes and neck to be protected with visors, eye shields, and neck protectors. The jet-style helmet is becoming more popular on an international stage. This style looks more like a motorcycle helmet, wraps around the head with no extended brim and allows for greater integration of eye protection, communication devices, and breathing apparatus. This helmet provides greater comfort and many customization options for firefighters.
Conclusion
Whether the fire helmet is thermoplastic, fiberglass, or leather, styled to be traditional, contemporary, or jet-style, it has served as the firefighters’ first line of defense for more than 300 years when facing the hazards of the job. When the call comes in, the fire helmet is the first piece of equipment a firefighter grabs. It’s personal. It’s tradition.
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About the Author
Vincent Lee is the Head Sales Manager for Bullard Asia Pacific with more than 17 years of engineering and sales knowledge. His technical expertise of the emergency responder market has been instrumental in advancing the use of thermal imagers in the fire service. If you have questions about thermal imaging, you can email him at vincent_lee@bullard.com.
