Tools & Technologies: A Revolution in PPE: Filament Twill Technology

March 1, 2015
Firefighter protective clothing is continually evolving

Every so often, personal protective equipment (PPE) technologies are introduced to the fire service that are considered “revolutionary” or “breakthrough” innovations. In the years that follow, these innovations continually evolve with a focus on improved firefighter performance. From self-contained breathing apparatus (SCBA) to thermal imagers (TIs), from turnout gear to turnout gear materials, fire service PPE is always evolving.

For an innovation to be revolutionary, it must do a few things. One is to change the way firefighters think, behave and perform while doing their jobs. To be revolutionary, the market shift must occur quickly and on a large scale, like a tidal wave. Finally, to truly be revolutionary, the adoption of the innovation must be considered a "no brainer" by the overwhelming majority.

A revolutionary innovation bypasses the norms of a firefighting culture that doesn’t like change to one that can’t function without it. One example of a revolutionary innovation introduced just a few years ago is fabric design for turnout gear outer shells and thermal liners called filament twill technology. So what exactly is filament twill technology and why is it revolutionary?

What is filament twill technology?

The filament in filament twill technology: A way of designing and manufacturing fabric with the use of DuPont Kevlar filament, usually 20%-60% Kevlar filament, in addition to spun yarns.

The higher percentage Kevlar filament content in an outer shell utilizing filament twill technology will have much higher tear strength and much better tear resistance after UV exposure than traditional outer shells using 90%-100% spun yarns. Because Kevlar filament yarns are so much stronger than traditional spun yarns, the outer shell can also be made lighter and stronger at the same time. If rips and tears after UV exposure are an issue, and they eventually are at almost every fire department, filament twill technology helps solve a problem.

The higher percentage Kevlar filament content in a thermal liner face cloth will have better slickness/comfort for donning and doffing, as well as improved mobility compared to traditional thermal liner face cloths using 100% spun yarns. If heavy, wet thermal liners sticking to a firefighter’s skin are an issue, and they are with almost every firefighter who experiences it, filament twill technology helps solve a problem.

The twill in filament twill technology

The process of designing and manufacturing fabric with the use of a twill weave for better flexibility, mobility and comfort compared to the traditional rip-stop fabric weave that is more restrictive, stiff and uncomfortable.

Put these two concepts together and the result is filament twill technology: outer shells and thermal liners that are lighter, stronger and more flexible/comfortable. This description sounds simple, so one might wonder how a seemingly simple fabric design could be considered revolutionary. How does turnout gear utilizing fabrics made with filament twill technology meet the criteria of “revolutionary” laid out above?

Changing the way firefighters think

Most people like wearing new clothes. A new sweatshirt, sweat pants, jeans, T-shirt...everybody likes new clothes. This mindset, however, hasn’t been true with firefighters and new turnout gear. The norm for firefighters is to keep their old gear...the gear that has been washed, worn and “broken in.
 Firefighters like their gear to fit like a “broken in” baseball glove and dread the idea of having to “break in” new turnout gear. With filament twill technology, the “break in” period is nonexistent. Without washing the gear, without wearing the gear, the gear feels broken in the first time the firefighter puts it on. The gear feels lighter and more comfortable due to the way the fabrics are constructed ‒ filament twill technology.

When turnout gear constructed with filament twill technology is worn in a wear trial against turnout gear constructed with conventional rip-stop technology, the gear with filament twill technology is chosen 100% of the time. More importantly, when the department makes the switch to gear with filament twill technology, firefighters embrace the change to new gear and actually look forward to receiving their new gear: the mindset has changed. The proof of this is seen with the large number of departments listed below who have switched to filament twill technology. Filament twill technology becomes a “no brainer.”

Changing the way firefighters behave

It should be well known that comfort, or lack of comfort, has a direct impact on whether or not PPE is worn properly. OSHA states the following in the Hazard Assessment document for selecting PPE (OSHA 3151-12Rf): “Employers should take the fit and comfort of PPE into consideration when selecting appropriate items for their workplace.”

The reason for OSHA’s position and statement: PPE that is uncomfortable is significantly less likely to be worn in a manner that protects the user from the various hazards the user will encounter. For example, if a bunker coat is stiff and uncomfortable, firefighters may not zip up properly or clip all the hook and dee closures as specified in the department’s standard operating procedure (SOP), they may not flip their collar up if it is too high/long or too stiff, etc. Firefighters are going to find ways to be more comfortable ‒ this behavior is part of human nature. By using more flexible and more comfortable outer shells and thermal liners like those that fall under filament twill technology, turnout gear is more comfortable and more likely to be worn as specified in the department’s SOP. Filament twill technology becomes a “no brainer.”

Changing the way firefighters perform

The improvement in lighter weight flexibility not only enhances the perception of comfort, it also improves the firefighter’s mobility. Filament twill technology allows firefighters to bend, crawl and flex with less restriction, less effort and less stress.

Better mobility leads to better performance by firefighters as they are able to stretch farther, crawl through entanglements more efficiently and squeeze through small openings easier. All of these tasks become necessary when firefighters are trying to save lives. Filament twill technology improves the firefighter’s performance, again making it a “no brainer.”

A market shift is occurring quickly and on a large scale. Consider this: Prior to 2013, there were no fire departments wearing outer shells with filament twill technology. Prior to 2013, almost every fire department in North America was wearing turnout gear with outer shells constructed with traditional rip-stop technology.

Fast forward to 2015, where almost every large metro department that has evaluated turnout gear and turnout gear materials over the last two years has chosen an outer shell with filament twill technology over one with traditional rip-stop technology. The same is true with thermal liners.

The list of large metro fire departments that have made the switch to turnout gear outer shells made with filament twill technology includes, but is not limited to: Houston, Philadelphia, Phoenix, Pittsburgh, San Diego, Montreal, Seattle, Portland, OR, Baltimore City, Mobile, Montgomery, Kansas City, (MO, Wichita, Tucson, Nashville, Honolulu, Broward and Palm Beach counties, FL, Raleigh/Wake County FD, Cobb and Dekalb counties, GA, Orange County, CA, and the list goes on. Add all of this up and you have a tidal wave of change.

Like every innovation, turnout gear outer shell and thermal liner fabrics will continue to evolve. What is done today will become the past, what is imagined today will become the future. As we wait for the next “revolutionary innovation” in PPE fabrics, it is safe to say filament twill technology has become the standard for many years to come.

GUY LUCAS, director of sales and marketing for Safety Components, has worked in the flame resistant (FR) textile industry for 15 years. Having sold FR fibers, FR fabrics and FR garments (turnout gear), he has acquired countless contacts and a wealth of knowledge in the world of flame-resistant materials.

Connect with Guy

Blog: firehouse.com/contact/11116938/guy-lucas

Website: safetycomponents.com

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