Bruce Teele, senior emergency services safety specialist at the National Fire Protection Association (NFPA), points out that while all firefighters face the same basic hazards, the type of fire can determine which boot is most appropriate.
“Boots are designed differently for firefighters’ needs, and to reflect their environment,” he says.
When fighting wildland fires, for example, responders may have to deal with challenging terrain, such as steep mountainsides or uneven ground. These firefighters, Teele says, need boots that can help stabilize the foot without restricting movement. Wildland firefighters often favor a rugged, leather boot that allows them to feel sure-footed even on unpredictable terrain.
According to NFPA 1977: Standard on Protective Clothing and Equipment for Wildland Fire Fighting, wildland firefighting footwear must comply with at least 11 performance standards:
- Heat resistance – The boot should remain functional under heat tests without melting or delaminating;
- Corrosion resistance – Metal parts, including aluminum, brass, copper, stainless steel and zinc components, should remain functional and not show more than a light surface corrosion;
- Cut resistance;
- Puncture resistance;
- Abrasion resistance;
- Conductive heat resistance – The inside sole surface should not exceed 111 F in conductive heat tests;
- Slip resistance;
- Attachment strength – The boot’s eyelets and hooks must be tested for attachment strength;
- Flame resistance – Footwear should not ignite, melt or drip, and should not have an afterflame of longer than two seconds;
- Label legibility and durability – Footwear labels should be legible and remain in place; and
- Sewing thread heat resistance – All footwear sewing thread should be tested for resistance to heat and should not melt, char or ignite.
Proximity and Structural Fires
Fire personnel working with high-heat proximity fires require a different boot design from wildland firefighters. Teele explains that proximity fire responders “face large amounts of radiant heat given off from flammable liquids, gases and possibly metals.” A firefighter in this situation may need more protection to ensure that the high heat levels won’t penetrate the boot.
Structural and proximity firefighters often are well served with a combat-style, lace-up boot that fits snugly. As Teele points out, these responders may prefer the agility a combat-style boot can offer. “It gives them more ankle support for working on ladders and roofs,” he says.
While working inside buildings, firefighters may encounter pooled water. Protection from moisture is important for any firefighter’s boot, but those who encounter water more often may prefer footwear constructed with a higher percentage of rubber-like, waterproof material.
NFPA outlines a separate set of footwear standards for proximity and structural firefighters in NFPA 1971: Standard on Protective Ensembles for Structural Fire Fighting and Proximity Fire Fighting. In general, these standards are comparable to those required for wildland footwear, but also cover additional areas:
- Liquid penetration resistance – The footwear should be able to resist penetration of liquid for at least 1 hour;
- Pathogen resistance – The footwear’s seams and upper material must protect against liquid or blood-borne pathogens;
- Puncture resistance – The footwear’s soles, heels and uppers must be tested for resistance to puncture;
- Electricity resistance – Footwear must pass an electrical insulation test;
- Toe impact and compression resistance;
- Bending resistance – The footwear’s ladder shanks must be tested for resistance to bending;
- Water resistance; and
- Flex cracking resistance – The boot’s puncture-resistance device should show no signs of flex cracking.
In addition, NFPA outlines specific standards for proximity firefighting footwear, including passing a radiant reflecting performance test and a thermal insulation test, where the temperature of the upper lining (the surface that makes contact with the skin) should not reach 111 F in 10 minutes or less. Standards specific to structural footwear include a radiant heat resistance test and a conductive heat resistance test.
Treading Lightly
In addition to design, materials and construction, tread is also an important part of the boot’s makeup. Teele explains that determining the best type of tread for firefighters’ protective footwear can be tricky. He says that in general, many test methods evaluate slip resistance as it applies to other industries – such as food service employees working on smooth concrete floors – instead of considering environmental factors unique to firefighters.
According to Teele, the variation in what some firefighters might need in footwear treading makes it too difficult to prescribe one ideal type. In fact, he likens the options to car tires because each variety may serve a different purpose. Some car tire manufacturers, for example, make tires that can stop quickly from high speeds, while others boast best stopping ability in wet conditions in lower speeds. Firefighters, meanwhile, may require different types of tread based on their work conditions. A responder who works on pitched roofs will likely need a different type of tread from one who works on natural terrain.
In Teele’s experience, fire departments try various types of boots and determine what works best for them. “Fire departments tend to field test models [of various materials and tread design] to fit their needs,” he says.
Fit and comfort also are personal choices that can affect each firefighter differently. “Sizing of footwear is an important issue,” Teele explains. “We know that even with our everyday wear, an improper fit hobbles you considerably.” He says the NFPA recommends that each firefighter is individually sized to ensure a properly fitted boot.
Extreme Conditions
On Sept. 11, firefighters battling the blaze within the Pentagon faced an unexpected complication. The Pentagon’s heavy, enclosed construction allowed heat levels to soar. This high heat, combined with the long durations responders spent in the building, damaged some of the firefighters’ boots.
“The heat built up and caused a separation of the sole from the upper [part of the boot],” Teele says.
Other unusual conditions, such as the presence of large quantities of aviation fuel, created a unique firefighting situation, and one that posed a footwear problem Teele says he hasn’t witnessed at any other time. The circumstances that led to boot separation on Sept. 11 prompted the use of fire-resistant stitching to bind the sole to the upper.
The design, construction and makeup of protective footwear include many variables and do not produce a universal solution for every firefighter’s needs. Even when all standards are met, an unexpected situation, such as the events of Sept. 11, may cause safety personnel to rethink their boots. Firefighters therefore need footwear that complies with standards and offers comprehensive protection – while also meeting their own requirements and preferences.