Posted October 4, 2017

 

By Devin Steele

 

Editor’s note: This article originally appeared in AATCC News on August 8.

 

Technology and innovation in the flame resistant (FR) and protective textiles arena continue to improve as the industry responds to the wishes and needs of first responders, the military and other sectors where people such as lab scientists and electric and gas employees are often exposed to potentially hazardous conditions or situations.

 

For years, a demand for clothing that provides protection AND comfort has increased, and a growing need for garments that provide multi-hazard protection (FR, arc flashes, chemical splashes, steam or hot liquid, etc.) has been seen. Comfort, it is reported, is often a major factor in employees choosing not to wear FR/protective clothing compliantly.

 

As such, fiber and fabric manufacturers are constantly seeking better ways to improve properties such as flex or stretch, breathability, moisture transfer, feel/softness, drape and suppleness – while providing protection against various hazards and meeting regulatory standards.

 

Trends and developments

 

In the FR arena, as the industry continues to increase focus on comfort, much research and development lately has been aimed at helping to provide solutions for workers, whether it’s battling the heat, cold or inclement weather, according to Craig Tutterow, technical director of FR Fabrics for Mount Vernon FR, Trion, Georgia, USA.

 

“FR fabrics have historically been perceived as uncomfortable to wear as daily workwear,” Tutterow said. “Much of the R&D is geared toward increasing comfort while maintaining protection and performance demands. The goal is getting workers to wear Flame Resistant Clothing (FRC) correctly and consistently.”

 

In recent years, Steve Lucas, senior FR technologist & development Engineer, Westex by Milliken, Spartanburg, South Carolina, USA, said he has also seen major improvements in this area. His company has especially made enhancements to clothing for people who work in certain settings such as laboratories. Most of those developments are comfort or lifestyle oriented, he said, and another is related to durability, he said.

 

“The comfort and the styling of FR fabrics have both made huge strides in the last decade,” Lucas said. “In my opinion, it is driven in part by the desire to offer FR work wear that is multi-use, meaning you can wear it beyond a job setting. It also is championed from a user standpoint, because wearers are more likely to wear FR apparel that is comfortable and suited to their lifestyle. Durability has also absolutely increased, which makes sense from a technical and longevity standpoint. The more durable the fabric is, the longer it can be safely worn.”

 

Among firefighters, the leading cause of death for years has been heat stress-related injuries or illnesses, so many companies are striving to create lighter weight turnout gear to address this issue, according to Brian Shiels, senior development engineer and group leader, PBI Performance Products, Inc., Charlotte, North Carolina, USA, which specializes in firefighter protection. Lightweight turnout gear that doesn’t compromise thermal protection has been the biggest improvement Shiels has seen in his area of specialty, he said. In a recently released study on U.S. firefighter fatalities, 2016 saw the lowest number of heat stress/overexertion firefighter fatalities (or Line of Duty Deaths, “LODDs”) since the annual studies began in 1977, but heat stress/overexertion remains the leading cause of LODDs.

 

“It’s certainly too early to attribute this to the lightweight protective ensembles, but it’s a good possible indicator that we’re making real change,” Shiels said.

 

Beyond comfort in firefighting protection, concerns over cancer and other diseases resulting from exposure to contaminants are rising, he added. A number of newly developed FR protective flash hoods that primarily provide heat and flame protection to the head, neck and face are incorporating some means of blocking particulate contamination from contacting vulnerable skin. Blocking particulates in smoke and soot may provide some protection against carcinogens, Shiels said.

 

Developments

 

For comfort and durability, one of Mount Vernon FR’s most distinct developments of late is AMTEX TC, a cotton/Tencel or cotton/Tencel/nylon blend. Incorporating Tencel into the blend increases both comfort and durability without sacrificing protection, the company touts.

 

“Tencel is a cellulosic fiber similar to cotton, but with added strength to create protective fabrics that are more durable,” Tutterow said. “Despite its strength, the addition of Tencel allows AMTEX TC fabrics to feel lighter than they actually are, which enhances the comfort of garments made with the fabric, especially in the heat. Enhanced comfort increases the probability that workers will wear garments correctly, and reduces risk of injury due to improper wear.”

 

Mount Vernon FR also developed FlexTex fabrics, which include an elastomeric fiber that allows the fabric to flex up to 14 percent, with a 97 percent recovery, Lucas said. The fiber addition adds mobility to fabric with no reduction in FR protection, he added. The FlexTex collection was expanded this year.

 

Related to durability, INVISTA’s CORDURA® brand recently teamed up with European specialist in military, workwear and industrial protective fabrics, Carrington, Lancashire, U.K., to offer a flame-retardant fabric engineered with CORDURA® NYCO technology to enhance durability. Designed to protect against multiple hazards in extreme industrial environments, Carrington Flametougher 280AS made with CORDURA® NYCO fabric technology for enhanced tensile, tear and abrasion resistance offers a multi-norm flame retardant treated solution that meets electric arc performance of 13.5 cal/cm2 (EN 61482-1-1), according to INVISTA.

 

What’s unique about Carrington’s 280AS fabric is it’s not just designed to meet a singular spec,” said Cindy McNaull, Invista’s global Cordura brand and marketing director. “As a multi-norm, flame-retardant fabric, you have some great features and benefits built into it. And you not only get flame-retardant protection, you get electric arc protection too.”

 

With Cordura, INVISTA has been involved in the fiber and fabric durability arena for many years, particularly for military and workwear applications, so it comes at the protection market from a solid foundation, McNaull said. Based on customer feedback and working with global partners, the company has taken the same kind of rigor and discipline into the protective-wear market, she added.

 

As a result, INVISTA developed a whole collection of Cordura NYCO fabric technologies to bring comfortable, durable protection that offers not only durability but comfort and next-to-skin benefits such as breathability, stretch and moisture management, she said.

 

In addition, INVISTA debuted tactical gear and apparel featuring No Melt No Drip CORDURA® NYCO uniform fabric and Solution-Dyed Nylon (SDN) CORDURA® Classic fabrics for enhanced Near-Infrared protection, and, just this year, unveiled its strongest nylon 6,6 staple fiber designed to enhance the core strength of CORDURA® fabrics. The INVISTA T420HT fiber has a mission to create a new generation of durable, yet lightweight fabrics, to be used in many applications such as military uniforms, outdoor apparel and workwear, McNaull said.

 

“It's really all angles of protection, with high visibility and the FR pieces being what you typically think of when you think of protection,” she said. “But there are other forms of lightweight comfort protection as well as protection from your infrared.”

 

A lot of Westex by Milliken’s R&D efforts have stemmed from filling a need in the marketplace, Lucas said. For example, Westex ShieldCXPTM sought to fill a major gap in comprehensive personal protective equipment (PPE) for university and commercial laboratory workers. Until Westex ShieldCXPTM, lab coats did not provide multi-hazard protection for both flame resistance and inadvertent chemical splash, he said.

 

Layering multiple pieces of PPE to protect against these hazards also presented a challenge of comfort, and therefore, consistent use of appropriate products was an issue, Lucas added. But the innovation created a breathable, comfortable fabric with both flame and inadvertent chemical splash resistance as an answer to market need, he said.

 

PBI Performance Products has developed and continues to develop lighter weight PBI fabrics to combat the heat stress issues in the fire service, Shiels said. Because PBI will always put protection as a top priority, PBI’s Lightweight Gold System™ provides protection without compromise, he added.

 

“In other words, our developments are geared towards providing lighter weight solutions with no negative impact on protective properties,” Shiels said. “Together with various partners throughout the fire service industry, PBI Performance Products is also engaged in development of Particulate Blocking Hoods to combat potential cancer risk of smoke/soot particles contacting the skin around the head and neck. PBI Performance Products also participates on various collaborative research efforts to study and improve cleaning and decontamination of firefighters protective clothing.”

 

Testing, testing …

 

Testing against standards and product specifications is a major part of Westex by Milliken’s processes, as well as Milliken & Company’s, Lucas said. Data from these tests reinforce the viability and the reliability of its products, and various testing is a core part of our quality control process, he added.

 

Using Westex ShieldCXPTM as an example, Westex by Milliken came across a significant challenge in the development stages of this fabric, according to Lucas. A lot of liquid repellency testing standards are written for either primary protection or impermeable fabrics such raincoats or slickers, he said.

 

So since Westex ShieldCXP™ is for secondary protection, the company modified the AATCC 193 test method, Aqueous Liquid Repellency: Water/ Alcohol Solution Resistance Test, in order to account for the various inadvertent chemical splashes the fabric resists and the breathability the fabric provides, he said. Westex by Milliken ran the test method with the same timing and the same scale of permeation as the original AATCC 193 method to create a modified version that could easily be replicated for future data and training uses, he pointed out.

 

Mount Vernon relies on unique test methods developed by the University of Alberta to evaluate products used for protection against hot fluids, steam or flash fires, Tutterow said. These methods will be incorporated in the new edition of the CGSB 155.20 standard, expected to be released later this year, he said.

 

In the Canadian oil sands, hot water and steam are used to extract bitumen, so workers need protection, he noted. “Steam and hot liquids are capable of transferring energy much more efficiently than other thermal hazards, requiring different protective fabrics,” Tutterow said.

 

At PBI Performance Products, no widely accepted solution exists for testing the new particulate blocking firefighter hood materials, Shiels said. NFPA 1971 is considering adopting an alteration to ASTM F2299, which is a medical facemask filtration efficiency test, and it would be used to evaluate the particulate blocking hoods, he noted. 

 

“Another exciting and constantly evolving area of testing is full-ensemble testing,” Shiels said. “There are several old and new technology-based test systems to evaluate full protective clothing ensembles (as opposed to just fabrics). There are instrumented flash-fire manikins to evaluate whole ensemble thermal protection; there are instrumented sweating thermal manikins to evaluate protective clothing comfort; there are both manikin and human-subject systems that can be used in the MIST test to evaluate whole ensemble protective clothing for chemical protection. With so many aspects of FR protective clothing required to work together, ensemble level testing is becoming more and more important.”

PBI Performance Products uses a wide variety of AATCC/ASTM/ISO test methods on a daily basis, he added.

 

Efforts to preserve life and limb continue

 

As people unfortunately continue to get hurt on the job, dozens of companies in addition to these four are also working diligently to improve the inherent and multi-hazard qualities of protective garments while increasing the comfort level. Much improvement has been made in recent years, but R&D in this area is an ongoing effort that will continue to preserve life and limb of those who work almost daily in vulnerable conditions.