Historically, the flame resistant properties of flame resistant fabrics could be separated into two categories: Inherent and treated. Once upon a time, this was a relevant distinction. It meant the difference between FR properties that were durable, and those that were not. However, these terms ceased to provide information to safety managers looking to evaluate FR fabrics way back in 1987.
Broadly speaking, ‘inherent’ fabrics are those whose engineering does not involve addition of flame retardant chemistry – their FR properties are “inherent” to the fiber; while ‘treated’ fibers and fabrics that are engineered from a flammable base fiber and flame retardant chemistry. When these terms were co-opted for use in the FR world over 30 years ago, they reflected the durability of flame resistant technology at that time. But advancements in FR engineering and manufacturing have blurred or eliminated the lines between the two sides. Today, ‘inherent’ and ‘treated’ are, essentially, marketing terms with little to no basis in FR science, and are used regularly with little to no consistency of application from fiber to fiber, fabric to fabric, or year to year. Basically, they’re useless when it comes to helping any objective person to evaluate many of the flame resistant fabric products on the market today.
The properties most important to wearers of flame resistant apparel are protection, comfort and value. Durability of these properties is critical. What matters most is that garments are made from an FR fabric that retains its flame resistant properties for the life of the garment –– and that the fabric has a proven track record of success. Evaluate factors such as independent lab test results, time on market and brand reputation — these areas will offer greater insight into a fabric’s quality than clever marketing ever could.