The sun has barely started to peer over the horizon when one of Casper’s dozens of hardworking linemen awakens to begin his day. Once at work, he views his work orders and realizes that he and his team are being called out to address a power outage in another region. He knows he must already endure a ten-hour workday today. But, this callout could easily mean that the lineman won’t be able to return home to his family until well into the night.
Long days aren’t even the worst of his worries. On any given day, linemen must combat severe weather conditions, confined space work, extreme fall hazards, and even potential fire and arc flash hazards. One wrong move may cause them to fall victim to shocks, explosions, burns, falls, and more.
- High-voltage contact
- Working at height
- Challenging weather conditions
- Welding, cutting and burning
- Confined spaces
- Fires and explosions
A diverse array of hazards makes having the right protective gear even more crucial. In many cases, this means fire-resistant (FR) clothing. Working around high-voltage materials and fire hazards, or performing work as a welder are just some examples of occupations that require FR clothing.
If you work in one of these industries, you already know the purpose and importance of flame-resistant gear. But, what actually makes FR clothing fire-resistant? What materials contribute to that protective factor?
No, you’re not watching the Discovery Channel, and this isn’t an episode of “How It’s Made.” But, having an insight into the science behind FR clothing will help you be more informed about what products work. A better understanding of this unique type of PPE will help you make smarter buying decisions.
If you’re simply curious about how and why your FR apparel works, that’s great too. The more you know, the safer and more successful you’ll be on the job. Now, it’s time to answer the burning question…
What makes FR Clothing fire-resistant?
Before we talk about what’s in FR clothing, it’s important to know what it’s not. Though not the only industry to wear this type of PPE, the electric power industry is one who has a substantial need for fire-resistant protection. One of these workers’ most serious threats is electric arcs. Hazards from arc blast or flash include:
- High temperatures over short periods of time,
- Hot gases,
- Intense pressure waves from explosions, and
- Shrapnel from vaporized and molten metal particles.
It’s easy to see the potential lethality of these dangers. That’s why OSHA introduced the "269" standard (1910.269(l)(6)). “269” states that workers must be trained in the potential hazards of electric arcs. Returning to the topic of FR clothing, the standard also prohibits workers from wearing PPE that may amplify the potential of injury in the presence of an arc.
Clothing that may ignite, that will continue to burn, or that may melt on the skin is out of the question. So, FR apparel is not crafted from synthetic materials such as acetate, nylon, polyester, or rayon. This means you probably won’t want to wear your “dri-fit” athletic apparel under your FR coveralls while welding.
OSHA provides a general explanation for what may be considered FR clothing. This requirement states, “Clothing made from 100% cotton or wool may be acceptable if its weight is appropriate for the flame and electric arc conditions to which a worker could be exposed.” (There are many conditions to this rule though, so check the link for more information.) This basic work shirt is a great example of 100% cotton FR gear. Keep in mind, it may not adhere to the protection rating required by your job.
But, let’s dive deeper.
Ultimately, the fabric your FR clothing is constructed from determines its protection level, comfortability, and value. But, unfortunately, there aren’t many naturally occurring fibers. Even 100% cotton will ignite and burn when exposed to an ignition source. So, the majority of the fibers in your FR gear have been engineered to be fire-resistant.
Treated Vs. Inherent
When assessing FR apparel, know that over-simplified or vague terms, such as “treated,” may mean that the product’s protection will not be up to par. Many “treated” FR clothing items only offer topical and/or temporary protection. With repeated wear and washes, your 100% cotton gear may lose its fire-resistance, durability, and comfortability.
The same is true for FR garments labeled “inherent.” According to Westex, “what is commonly marketed as ‘inherent’ could actually be synthetic fibers that begin as naturally occurring flammable substances.” Many inherent fabrics, as well as treated fabrics, will char rather than burn.
FR “treatment” is a process, while the term “inherent” refers to the garment’s input fiber or material. An effective piece of FR gear undergoes a lot of science and engineering to provide you with the proper protection. That’s why it’s essential to be informed. Choosing your FR PPE based on one factor may not mean that it has the performance results you need. Instead, you must look at the bigger picture. Some of today’s most advanced FR fabrics are crafted from a combination of both treated and inherent fibers. For example, this hooded sweatshirt is constructed from a blend of fibers that allow for its effective protection.
PPE Protection Categories
If you use or are familiar with FR gear, you’re aware of the hazardous risk category levels, numbered one to four. Category 1, or CAT 1, has the lowest amount of risk, while CAT 4 has the greatest level of hazard. The levels are rated to have a certain level of fire-resistance, measured in cal/cm2. Depending on your risk category level, your PPE is required to have a specific arc rating. For example, CAT 3 hazards require PPE with a minimum arc rating of 25. Wearing multiple layers of FR clothing can help increase your arc rating.
The National Fire Protection Association (NFPA) and their 2112 standard provide performance criteria for FR clothing. This standard in particular details numerous guidelines for a garment’s design, performance, certification, and test methods. Bulwark products that are NFPA 2112 compliant have been certified by Underwriters Laboratories (UL) or other third party laboratories to meet the necessary requirements of NFPA 2112. Various other manufacturers offer products that comply to this standard as well. It’s important to look for 2112 compliance, as well as the appropriate arc rating, when selecting FR products for your team or for yourself.
So, what is my FR gear made out of?
The short answer: it depends on the hazardous risk category level and the minimum required arc rating for your job. When it comes to fire-resistance, there is no “one size fits all” approach. Different jobs have different protection requirements, meaning each FR fabric has unique properties that may either help or harm the end user. However, blending different fibers can allow for maximum protection and performance.
Two common FR fabrics include 100% cotton and an 88% cotton/12% nylon blend. Bulwark’s line of EXCEL-FR® 100% apparel has been permanently treated to provide fire-resistance for the extent of the garment’s life. The brand’s ComforTouch® line uses a practical 88% cotton/12% nylon blend, and is engineered to provide guaranteed fire-resistance for the life of the garment. These fabrics are treated to provide fire-resistance. This treatment involves the application of a flame retardant. Some flame retardants are phosphonium salt precondensates that have been polymerized with gaseous ammonia. They may also be a heat-cured dialkylphosphonamide. The process used has minimal impact on the fabric’s performance.
- 100% cotton
- 88% cotton/12% nylon
- Tecasafe® PLUS
- CXP Nomex®
- Excel-FR® ComforTouch®
The various types may have different combinations of fibers, or may have undergone different flame retardant treatment processes. Still, the FR PPE you select will depend on the hazards of your workplace and the minimum required arc rating you need. It is not enough to consider only one facet when choosing FR gear. A comprehensive view is needed.
Stay Informed, Stay Protected
It’s not strange or unnecessary to want to know more about what goes into the making of your PPE. FR gear can only do its job if it has been engineered effectively, and if the right products are chosen for the job.
There are so many factors that go into choosing FR garments that meet your performance and protection requirements. Having a better understanding of the level of fire-resistance you need, as well as which products can offer that protection, will only keep you safer on the job.
Navigating the numerous FR products and fabrics on the market can be flat-out confusing. Don’t hesitate to reach out to us if you have any questions. Most importantly, do your research. Learn what level of FR protection is really needed for your specific job, and find products that will live up to those needs. Don’t be uninformed when your safety is at stake.