Flame resistant (FR) apparel refers to any clothing items that are designed and specifically manufactured to protect wearers from potential intermittent flames and thermal exposure.
Flame resistant apparel is appropriate for the flame and electric arc conditions to which a worker could be exposed. As heat levels increase, these materials will not melt, but they can ignite and continue to burn.
Flame resistant clothing is made from inherently non-flammable fabrics and materials. The materials have a chemical structure that is naturally resistant to flames. These types of fabrics may catch fire, but they will either self-extinguish or burn extremely slowly. The most important function of these materials and fabrics is to prevent the further spread of fire.
Fire resistant is a term synonymous with flame-resistant. If you hear this term used in place of flame-resistant, don’t be confused. They mean exactly the same thing, and it is correct to use them interchangeably.
Fire retardant fabrics, on the other hand, are those that have undergone chemical treatment to acquire some of the same properties that flame resistant fabrics have inherently. As a result of these chemical procedures, flameretardant fabrics become selfextinguishing and slow-burning. Any type of fabric may be used, but it must undergo this treatment before it can be considered flame retardant.
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. As heat levels increase, these materials will not melt, but they can ignite and continue to burn. The amount of heat required to ignite these materials is dependent upon a number of factors, including the weight, texture, weave, and colour of the material. This type of clothing does not comply with the “269” standard if it can ignite (and continue to burn) under the electric arc and flame 79 exposure conditions found at the workplace. If they do not choose FR clothing, employers need to make a determination of whether or not the clothing worn by the worker is acceptable under the conditions to which he or she could be exposed. FR clothing is acceptable with respect to the OSHA apparel requirements (OSHA, 2018).
Primary hazards
There are three broad categories of workers who should wear flame-resistant clothing for protection, based on the type of hazard to which the worker will be exposed while completing their work. Here are the three primary hazards.
Electric arc
People who are exposed to electric arc hazards include electricians, as well as certain utility workers and others.
Flash fire
This category includes pharmaceutical and chemical workers, as well as those who work in refineries and more.
Combustible dust
The category of combustible dust covers workers in food processing plants, the paper and pulp industry, etc.
“detailed information in the International Standard ISO 2801:2008, covers recommendations for selection, care and use of protective clothing”
Protection levels
Primary protection refers to flameresistant clothing that is designed to be worn during activities where the wearer will constantly be exposed to flames, radiant heat and potential molten substance splash. An example would include firefighter’s gear. The firefighter will be exposed to extreme conditions and will need the additional measures offered by primary protection gear.
Secondary protection is designed for situations where the wearer may encounter exposure to intermittent hazards. This may still include radiant heat, molten substance splash and flames, but the odds are that these will not be constant hazards. Rather, they may appear briefly before disappearing again. In other words, the wearer of secondary protection is not likely to be in as much constant danger as the wearer of primary protection.
FR fibres
Most flame resistant clothing is made from fabrics that are a blend of several different materials. These materials are almost always synthetic. They have been carefully engineered and designed to be self-extinguishing and slow to ignite. Not all fire resistant clothing is made from the same fabrics. There are multiple choices available, and no choice is perfect. Each comes with different benefits and hazards. Each company is best served by choosing the fabric that will be most suited to their needs and working environment. What keeps an employee safe in one location may not be exactly what keeps an employee safe in another location.
Here are a few of the common fibres with inherent flame-resistant qualities commonly used to create FR clothing.
Modacrylic
Modacrylics are the most popular and common option available today. These fibres are often used as part of a blend to create several different flame resistant fabrics. These various combinations of fibres work together to create fabrics that can easily stand up to several types of standards and regulations.
Nomex
Nomex is another type of fibre that has inherent flame resistant qualities. Unlike modacrylic fibres, Nomex can create FR garments on its own. It doesn’t have to be a standalone, however, since it can also be combined with other materials such as Kevlar.
Kevlar
Kevlar fibres are certainly flame resistant, but have many other additional properties such as high strength. Kevlar can create flame-resistant clothing, as well as many other different items. When used to make FR clothing, Kevlar is often combined with Nomex.
Each type of flame resistant fabric will come with its own pros and cons. Kevlar, for instance, is extremely heavy duty, but comes with a high price tag because of it. There are no specific flame resistant clothing dangers, however, and all are designed to protect the wearer from hazardous heat based conditions.
There are numerous avenues of exploration and investigation out there for anyone seeking an FR programme solution. The most important aspects to be considered should be based on your own hazard and risk assessment.
Initial criteria should examine the following:
- Make sure that the FR garment/ fabric you choose is compliant and/ or certified to all of the appropriate standards and OSHA regulations
- Choose the style and weight of FR garment that will best suit your environment and the needs of your workers
- Think about the overall wear life of the garment and what the cost will mean long term
Summary
FR garments and fabrics are not one size fits all, so be sure to choose the one that will make you feel the most confident in terms of protection, comfort, and durability. There is also extensive guidance material available with more detailed information in the International Standard ISO 2801:2008, which covers clothing for protection against heat and flame with general recommendations for selection, care and use of protective clothing.