By Jeffrey O. Stull

Many clothing problems, such as tears, charring and heat damage, are fairly obvious. However, some areas of clothing are not easily inspected. For example, it’s hard to determine when the trim on clothing has diminished nighttime reflectivity (NFPA 1851 prescribes a simple check of clothing trim with a flashlight to determine the relative intensity of the clothing trim).

Particular problems have occurred with some liner materials. A couple of years ago, concerns arose over the use of a specific moisture barrier. Because the film side of the moisture barrier is positioned so that it faces the thermal barrier and the two materials are sewn together (forming the liner), it is especially difficult to inspect the condition of the barrier film. In this case, unexplained deterioration in the form of color changes, flaking and eventual disintegration often went unnoticed, leaving the firefighter without an effective moisture barrier. NFPA 1851 provides a recommended test involving the use of a water-alcohol mixture that allows end users to evaluate parts of their moisture barrier, but this test is difficult to apply uniformly over the entire moisture barrier. Given the magnitude of this specific problem, Texas required all career fire departments using the moisture barrier in question to replace the liners or their clothing.

A similar situation has arisen with the use of PVC-based cellular foam materials in firefighter protective clothing, which likewise face the liner interior. These materials are susceptible to early stiffening, embrittlement, cracking and flaking from high heat exposures or permanent compression without the firefighter realizing any change in their clothing and overall protection. Although you may be able to feel stiffness and crumbling, you would have to remove the liner’s stitching to definitively prove damage. However, a liner, once opened, would then require professional repairs.

Jeffrey O. Stull is President of International Personnel Protection, Inc., which provides expertise on the design, evaluation, selection and use of personal protective clothing and equipment and related products to end users and manufacturers. He has been a member of the NFPA committees on Protective Clothing and Equipment for the past 18 years.