EVALUATING FR FABRICS
Keys to Evaluating and Comparing FR Fabrics
The first step when deciding on your best choice for FR is to search out and evaluate information that was generated using the following three criteria. By doing this you can evaluate different types of FR fabrics on a level playing field and ensure that you’re comparing “apples to apples.”
- Identify your potential hazard. Exposures such as electric arc flash and flash fire are unique hazards with vastly different characteristics and the test results do not directly correlate to one another. The results from flash fire testing should not be substituted for electric arc flash testing when evaluating products. Be wary of fiber and/or fabric producers that attempt to draw comparisons between these two hazards.
- Identify industry consensus standards for the exposure. Industry standards have been developed for electric arc flash and flash fire testing. For electric arc flash, ASTM has developed F1959, which produces an ATPV (Arc Thermal Performance Value). NFPA 2112 was created for employees that work in environments where a potential flash fire hazard exists.
- Make sure the testing is conducted at independent laboratories. This will help ensure that unbiased and scientifically valid data is being produced. While it is often helpful and interesting to witness testing conducted by a company that has a vested interest in the FR business, there is no substitute for information generated at an independent laboratory.
Engineered Flame Resistant Fabrics
Engineering flame resistance into fabrics can be achieved either through the application of a flame retardant chemical, as with Westex engineered fabrics, or as a property of a synthetic fiber, such as Nomex®. Since passing the vertical flammability requirements is an essential criterion for protective clothing fabrics, viable flame resistant fabrics should remain flame resistant throughout their useful service life. Westex UltraSoft®, UltraSoft AC®, Indura® and Nomex® fabrics are acceptable for protective clothing because they each self-extinguish and pass the vertical flame test throughout their service life. Therefore, more specific tests should be further employed to assist in comparing the protective characteristics of each fabric. The performance of UltraSoft® and Indura® to electric arc and flash fire exposures will be compared to Nomex® elsewhere on the website.