Evaluating flame-resistant garments
Answered by Scott Margolin, international technical director, Westex Inc., Chicago.
You are right; it is unwise to permit any fabric or garment that simply passes industry consensus standards such as 1506 and 2112. Many different flame-resistant fibers, fabrics, blends and weights are available in the United States. Each one provides different levels of thermal protection, comfort, durability and cost. Sorting out all the marketing claims can be a time-consuming and frustrating process, leading some people to elect to accept any fabric that meets the appropriate standard.
These and other performance standards are excellent diagnostic tools and provide independent and quantifiable pass-fail results. However, it is critical to understand that these standards were designed to represent minimum performance criteria. They are intended to be used as the starting point when evaluating flame-resistant clothing. Compliance is an excellent qualifier to see what products "make the race," but it does not show winners; thermal protective performance data and years of market-proven performance define winners.
Flame-resistant products worn for arc flash or flash fire protection that cannot pass these standards do not belong on-site or on your employees. On the other hand, many products will easily pass that, upon more thorough review, may not be among the best options to protect your people.
Durability of FR properties to laundering over time also is a consideration. For instance, 1506 requires that fabrics pass vertical flame tests when new and after 25 wash/dry cycles. However, 25 laundering cycles represents six months to a year of use, while most FR garments worn for arc flash protection will be in service for three to four years. Thus, while compliance ensures a minimal level of FR durability, it does not indicate flame resistance for the service life of the garment. Significant additional testing is necessary to definitively demonstrate truly durable FR properties.