3 Things that Make Globe Boots Safer and the Science that Proves Why

By Rob Freese, Sr. Vice President of Sales and Marketing at Globe

Boots

When we got into the leather fire boot business 10 years ago, people told me it was a mature and saturated market. Little did they know where our imagination would take us. That’s because we listen to what you, the firefighter, tell us you need to perform your duties effectively and safely. And then, as part of our product development process, we rely on science to study exactly how the human body moves.

Boot Construction

For years, all firefighter boots were made of rubber. They were waterproof, but they were also hot, heavy, and clunky. In the 80s, advances in materials made the development of a new kind of fire boot possible – constructed with leather on the outside and a waterproof, breathable bootie on the inside. They were lighter, more comfortable, and a huge improvement.

Some leather fire boots are made with Goodyear welt (stitched) construction. The end product is a boot that is flat as a pancake and stiff as a board. The stiffness is a consequence of the welt construction method in combination with the steel plate.

Boots made with athletic footwear (cement) construction are flexible like your feet. Your feet are designed to flex 50 degrees. If your boot doesn’t flex 50 degrees, then your movement will be restricted.

Other leather fire boots are made with a hybrid construction method. It starts with a cup outsole like athletic footwear construction but uses a creased steel plate along the bottom and then injects urethane foam. Again, these boots are stiff by the very nature of their construction.

The Science

NIOSH: Boot Weight and Sole Flexibility

The National Institute for Occupational Safety and Health (NIOSH) set out to quantify to what extent lighter weight fire boots would reduce exertion and physiological strain on firefighters. The three phases of study included men and women firefighters and tracked physiology and biomechanics during simulated firefighting tasks:

• Phase 1 – Effects of boot weight and material (leather vs. rubber)
• Phase 2 – Effects of sole type (stitched vs. cement)
• Phase 3 – Effects of weight, sole flexibility, and material on risk of slips/trips

A peer-reviewed article in Human Factors: The Journal of the Human Factors and Ergonomics Society proved that lighter weight and more flexible footwear isn’t just about comfort – it’s about safety. The NIOSH study found:

• Lighter weight = Less work
• More flexible (cement construction) = Less work
• More flexible = Less trip and fall accidents

SATRA TM 194: Flexibility

Weight is an obvious measure. But how do you measure flexibility? SATRA is the go-to independent testing service for the footwear industry and has developed most of the industry standard tests. Globe boots have been tested by SATRA (TM 194) for flexibility and are the most flexible firefighter boots you can buy.

SATRA TM 144: Slip Resistance

Slip resistance is also a critical safety issue. So how do you measure slip resistance? This is another industry standard test from SATRA (TM 144) that measures slip resistance on a variety of standard test surfaces.

This test rated Globe boots on wet and dry quarry tiles and frosted rough ice with results represented as a coefficient of friction. The numbers show that Globe’s unique VIBRAM® sole has high slip resistance on ice and slippery surfaces.

Our soles are made from a Neoprene-based compound to stay flexible and maintain grip in low temps, wet, and ice. Gasoline hoses are made from Neoprene because they stay flexible in the cold and resist water and a wide range of chemicals.

And because our boots are more flexible, you get more surface area in contact with the ground, so in the real world our results are even better than the flat conditions measured in the lab.

ASTM F 2413: Composites vs. Steel

How protective are composite penetration-resistant insoles?

Rather than create their own test methods and test values, NFPA 1971 (and 1951) adopted industry standard ASTM tests and test values that are used across all industries. For example, the construction industry faces similar hazards to those encountered by the fire service in residential, commercial, and industrial construction projects.

The core of the minimum requirements in ASTM F 2413 is:

• To flex 1.5 million times without cracking or delaminating; and
• To resist puncture by a test pin at 1200 Newtons (270 lbf).

Steel plates are engineered to meet the minimum standard. But the PunctureX composite we use in our Globe boots is engineered to exceed the standard by 25%.

The test results also indicate that there is a difference in how steel fails and how the composite fails. Steel resists for a short period of time and then fails all at once when it reaches a force just above the minimum requirement. It takes a longer period of time for the composite to fail, at a force significantly higher than the standard. And it continues to provide resistance to penetration even after penetration starts to occur.

The bottom line:

• Composites are more penetration resistant than steel.
• Composites are dramatically warmer in winter, as they are insulators rather than conductors.
• Composites allow us to make boots that are dramatically more flexible

3 Things that Make Globe Boots Safer

1. Athletic Footwear Construction. All Globe boots are built with an athletic footwear construction so they’re flexible like your feet. Every layer of the platform on which they’re built is cushioned and contoured like athletic shoes. And Globe boots fit so securely, you can even run in them. More flexible boots are safer.

2. VIBRAM® Contoured Cup Outsole. Our molded outsole wraps onto the leather upper for athletic shoe performance. The flame-, abrasion-, oil-, acid-, and slip-resistant compound is engineered for high traction and durability, even during prolonged exposure to extremes of heat and cold. The tread on all Globe boots feature siping – thin slits cut into flat areas across the sole – that opens up when flexed to provide additional traction on water and ice. The self-cleaning lugs and omnidirectional tread pattern is designed for superior performance in all terrains and when working on ladders. The result of these design features is that Globe boots grip like no other. Better gripping boots are safer.

3. Advanced Composite Components. Composites are lighter and stronger than steel. That’s why they are used increasingly as components in airplanes and cars. Globe boots use composites instead of steel for safety toe caps, shanks, and penetration protection. These composites are more than three times more expensive than steel so we are using them because they are critical for performance and safety. More penetration-resistant insoles are safer.

What you put on your feet really makes a difference. Our intention 10 years ago was not to enter the fire boot market with a “me too” product – and we didn’t. We are known for making boots that come the closest yet to feeling like your favorite sneakers. And more importantly, they are the safest fire boot on the market – inspired by what you need to perform your firefighting duties effectively, and backed by science.

Check out our complete line of NFPA-compliant athletic footwear for firefighters.