Studies in the performance of fire-resistant woven fabrics for Australian firefighting station wear

Unlike Turnout Gear, the significance of Station Wear (i.e. daily work wear) and the protection that is provides, has been largely overlooked by researchers, Fire Services and firefighters. Station Wear refers to the middle clothing layer in the protective ensemble worn by Structural or Wildland firefighters. It should provide protection from hazards encountered during non-primary firefighting operations. An evaluation of the current materials used in Australian Station Wear confirmed inconsistencies in their fire-protective performance. Other studies have also highlighted the need for improved heat and moisture transfer capabilities through protective clothing materials worn next-to-skin, to assist human thermoregulation and reduce firefighter activity-related hyperthermia and fatigue.<br> <br>The purpose of this research was to develop a new fabric suitable for firefighting Station Wear to improve heat and flame resistance, durability, strength, and thermal comfort performance properties in a light-weight alternative to current commercial choices.<br> <br>Eight Station Wear woven fabrics were developed using a common aramid warp and different weft yarn blends of Nomex®, FR Viscose and merino to achieve a range of desired properties. Because no performance-based Australian Standards specifically apply to Station Wear materials, the quality and performance of the eight Experimental fabrics were evaluated against a selected Commercial Control fabric (MCA), using selected Standard tests intended for outer-shell (Turnout) materials. These identified the best-candidates for Station Wear or work applications where fire-protective capability is important.<br> <br>A variety of strength, flammability and comfort tests were performed before and after UV irradiation. Results indicated that fibre composition, yarn strength, weave structure, and fabric weight mainly influenced these properties. Two of the eight best-performing Experimental Station Wear fabrics progressed to further testing. Those identified as B1W2 and B3W2 were selected because they exhibited very good-to-excellent fire-resistance, tear strength and thermo-physiological comfort properties superior to those of the Commercial Control.<br> <br>Replacing Station Wear based only on the number of years in-service unnecessarily places the firefighters at risk of injury, especially since such protective work wear is worn daily and laundered frequently. Therefore, effective user-friendly Station Wear required consideration of durability and service life.<br> <br>Subsequent UV irradiation of the Commercial MCA, B1W2, and B3W2 fabrics, subjected to a single, 14 day exposure using an artificial light source (500 W, MBTF), was followed by two significant assessments of the tear and flame performance of these three fabrics. It was confirmed that UV radiation negatively impacted not only the mechanical properties of the Commercial, and the two Experimental aramid-blend fabrics tested, but also their flammability performance. Generally, UV-induced degradation increased in fabrics with higher meta-aramid blends. Prior to UV irradiation, B1W2 and B3W2 outperformed the Commercial MCA fabric. Post-exposure analysis confirmed the premature mechanical failure of all three fabrics, which fell below the minimum Standard requirements for Turnout Gear. Therefore, the need for a new Work Wear Standard specifically developed for Station Wear materials was recommended to clearly define fabric performance requirements, and expectations once in use.