Commentary: Are moisture barrier “failures” really failures?

Since the NFPA 1851, 2008 edition was published, testing moisture barriers and moisture barrier failures have been hot topics. Many fire departments are concerned that they will be subject to large moisture barrier replacement costs if their moisture barriers are regularly tested and fail. However, I wonder if the test and the reported test results have gotten a bad rep due to the fast and loose use of the word “failure”. Does a single water droplet produced by a pinhole leak mean that the moisture barrier has failed? In my opinion, a single water droplet doesn’t mean the moisture barrier has failed, but it needs to be repaired.

I don’t want to minimize the importance of moisture barriers within the composite construction of turnout gear. Each composite – outer shell, thermal liner and moisture barrier – plays a vital role in the protection of fire fighters.  In fact, it is the combination of characteristics provided by each composite layer that provides the protection required by NFPA 1971. The whole is greater than the sum of its parts. But I do wonder why we say moisture barriers fail when they leak, but a rip or tear in an outer shell, which protects the liner system, isn’t perceived as an outer shell failure.

In truth, I believe there are at least three factors that have caused us to look at any leakage as constituting “failure” in a moisture barrier:

First is the Pass/Fail rating used on most inspection forms to judge moisture barrier performance in the Water Penetration Barrier Evaluation. No water passing through earns a Pass.  Water passing through gets a Fail. There is no scale to differentiate between a water droplet squeezed through a pinhole under pressure and deterioration that allows water to pass through the membrane. The rating system is particularly misleading because it gives no indication between repairable and non repairable damage.

Which leads to the second point, there seems to be a blurring in definition between the words repair and replace. Is there a misunderstanding that fail doesn’t mean unable to repair? The Water Penetration Barrier Evaluation requires testing in three moisture barrier material areas and three areas with a seam. If there is leakage in any one of the areas, the moisture barrier has failed the test although 99% of it may be intact.  If the failing test area has a pinhole, puncture, rip or tear, or abrasion has caused weakness in that specific area, the moisture barrier can be repaired with a patch. Replacement is required when water is passing through the membrane or there are so many leaks that it is more economical to replace than repair.

Last is the misperception that all components used in the construction of turnout gear ages at the same rate and subsequently has the same wear life. Of course, there are a lot of contributors to this misperception from competitive marketing by component suppliers to the NFPA 1851 ten year retirement requirement. But if you think about it, turnout gear is made with a variety of materials ranging from a thin membrane to Kevlar® which is reported to be 5 times as strong as steel. So there are parts in gear that most likely will never reach ten years of age, but with proper use, care and maintenance including repair and replacement of some parts gear can conceivably last 10 years.  Moisture barriers, of course, often show signs of wear before other composite layers; therefore maybe they just “fail” to live up to our expectation.

This commentary was written by Vicki Smith, director of services marketing for Lion Apparel.