Firefighter PPE goes high performance
Reviewing the evolution of PPE fabrics and features
By Robert P. Avsec
The turnout gear that you use today is very unlike that used by your fire service predecessors from even the 1970s. The creation of Nomex by DuPont in the mid-1960s was the beginning of the end for the rubber raincoats worn by previous generations of firefighters in the United States.
But those first generations of turnout gear coats made from Nomex fabric were still a far cry from today’s PPE. At the time, the Nomex fiber was nearly twice the weight it is today. Those first coats were bulky and heavy because everything about the coat – the outer shell, the substrate, the corduroy collar – was constructed with Nomex fabric.
The evolution of fabric used for PPE
More than 50 years after its development, Nomex continues to be a workhorse fiber for the firefighter protective clothing industry because of its inherent properties for thermal protection and durability. The addition of other fire-resistive fibers in the construction of fabrics used for turnout gear (e.g., DuPont’s Kevlar) have provided greater strength and durability, while allowing fabric manufacturers to reduce the amount of Nomex. This has resulted in more durable fabrics, with reduced overall weight, while providing better thermal protection.
(Note: In a “tip of the hat” that just misses last month’s Women’s History Month, the DuPont chemist credited with inventing Kevlar was Stephanie Kwolek, the daughter of two Polish immigrants).
Today’s turnout gear and heat
Manufacturers of firefighter PPE tend to face two major challenges: 1. thermal protective performance (TPP) and 2. thermal heat loss (THL).
TPP measures how well the PPE’s three-layer system (outer shell, moisture barrier and thermal barrier) prevents heat from getting to the firefighter from a hostile fire environment (i.e., keeping the external heat out!).
THL measures how well that same three-layer system helps the firefighter wearing the protective ensemble to shed heat to the outside world (i.e., letting the internal heat out!).
While TPP has attracted the lion’s share of attention from PPE manufacturers in the past, today the greater challenge is how to improve the THL performance for turnout coats and pants. Heat stress – along with sudden cardiac events (SCE) prompted by heat stress – account for more firefighter line-of-duty deaths (LODDs) and line-of-duty injuries than any other cause.
New technologies, along with discovering new uses for existing technologies (e.g., CROSSTECH), have made it possible to give firefighter PPE better THL performance, while simultaneously reducing serious drops in thermal protection that can happen when a firefighter’s PPE gets wet, particularly from their own perspiration.
Turnout gear that stretches
Another contributing factor in firefighter heat stress and SCEs is how much a firefighter’s PPE works against them. The concept of firefighters as “tactical athletes” has gained the attention of PPE manufacturers when it comes to all elements of the protective ensemble, not just the coat and pants. As such, the fabrics developed for use in firefighter PPE have not only gotten stronger and lighter, but also more flexible. They have stretch!
Stretch fabrics are the foundation of athletic gear in almost every active pursuit, and finally, stretch fabrics have come to the fire service. PBI Stretch is the first outer shell fabric for firefighter PPE that’s compliant with NFPA 1971: Standard on Protective Ensembles for Structural Fire Fighting and Proximity Fire Fighting.
Using this new fabric, which is made from a performance stretch blend of PBI/ Kevlar, turnout gear manufacturers can now produce turnout coats and pants that have a body-contoured, less-bulky fit that provides an unprecedented range of motion.
Improved range of motion
Manufacturers have also improved range of motion for firefighters with features like articulation of the elbow, knee and shoulder areas of turnout gear, so that it works with the firefighter, not against them. Together with options such as longer coat backs, these enhancements add up to turnout gear coats and pants that minimize the potential for gaps in a firefighter’s thermal protection.
But what about firefighting boots? The past 10 to 15 years have seen more advancement in firefighter boot technology than in the previous 200 years combined! (Who’d have ever thought one could run comfortably in a pair of firefighter boots?).
Boot manufacturers haven’t just tried to improve the firefighting boot. No, they’ve “broken the mold” and started over! They’ve brought high-performance athletic shoe technology (e.g., basketball shoes worn by college and professional athletes) to the boot-design process.
The result? Boots that fit and function like those high-performance basketball shoes right out of the box because of features like:
- Continuous segmented flex panels;
- Cushioned and contoured outsole;
- Safety toe cap, penetration-resistant insole, and shank constructed with lightweight composite materials (instead of heavier steel components); and
- Water-resistant leathers (that are lighter than rubber) for use in high-flex areas of the boot.
Today’s firefighting boots not only fit and move better, but they’re more comfortable for long periods of wear. For that, boot manufacturers have followed the coat and pants manufacturers’ playbook, using new and existing fabrics and technologies to provide better protection from physical hazards (e.g., cuts, scrapes and punctures) while improving breathability.
Better than ever before
All this means is that today’s firefighter can be equipped with structural firefighting PPE that protects them from the thermal heat of interior firefighting better than ever before. And their turnout gear is designed better than ever to dissipate their body heat during structural firefighting. Definitely a win-win!
The views of the author do not necessarily reflect those of the sponsor.