W.L. Gore & Associates Inc. – Managing moisture in structural PPE
Today’s specialist structural fire kit is designed to protect the wearer from extreme heat and flame. In addition to thermal protection certification tests, whole garment ensembles are regularly tested on manikins equipped with sensors in flashover conditions to evaluate protection performance and resistance to serious burns. These tests are carried out in special test facilities and normally involve the ensembles being exposed to the flashover flames for eight seconds at temperatures in excess of 1000 degrees. Composite swatches of the fabrics used in the garment are also tested in laboratory conditions.
It is a modern day paradox of firefighter protection that the gear which will protect in the extremes of a flashover, does not always protect from burn injuries that can occur in sub flashover conditions. That is the type of injury that can occur when energy within the layers of the protective clothing is suddenly transferred to the firefighter, resulting at times in burns, but with no sign of any damage to the PPE or outer fabric.
While it’s essential that PPE is designed to protect from extreme conditions, firefighters do not face them every day. In normal fire-ground conditions it is possible that a firefighter can be exposed to radiant heat for relatively long periods of time, which transfers through a complex thermal energy mechanism inside the layers of their protective clothing. When clothing is then compressed against the skin, for example when a firefighter crouches or flexes an arm that energy transfers through and can result in a burn. In such scenarios, moisture plays an important role which is not taken into consideration in the different testing.
The presence of moisture within structural kit, accumulated from water spray or sweat has been associated with low energy transfer or “steam burn” phenomena.
While moisture captured in the outer layers of an ensemble takes heat away from the garment in intense heat exposure, if the garment is wet inside as well then the risk of burn injury increases.
Similarly, structural firefighting suits and fabrics are always tested in dry conditions. They are not tested wet, which doesn’t take account of the risks of burn injuries associated with low energy transfers.
The GORE® PARALLON™ System has been developed to specifically combat the risks associated with moisture and heat stress by introducing a unique new solution that incorporates a highly breathable Gore thermal barrier combined with a GORE-TEX® or CROSSTECH® Moisture barrier.
This is a unique use of two membranes encapsulating a layer of thermal protection that maintains breathability while wicking moisture away from the skin and out through the suit, simultaneously preventing liquid penetration from the outside.
Internal moisture is efficiently moved through the layers, keeping the thermal protective fabric dry and reducing the risk of steam or wet compression burns. Comfort and breathability is high, reducing the risk of heat stress and keeping the wearer cooler for longer.
In tests undertaken in wet conditions, the GORE® PARALLON™ System consistently maintained thermal protection, allowing more time to escape and reducing the risk of burns in extreme and emergency levels of energy as well as in sub-flash over situations.
The GORE® PARALLON™ is the result Gore’s multimillion dollar investment in research, testing and quality to always live up to the promise that its products are fit for purpose – without fail.
Gore operates a comprehensive quality assurance programme. That process starts in-house with product testing and extends throughout the supply chain to ensure that garments manufactured with Gore fabrics meet stringent performance standards.
Gore associates are experts in their field and have a detailed understanding about the environment that a garment will be worn in, taking into account the way it will be worn and all the environmental factors that may affect comfort and protection.
Firefighters have never had better protection, however there is no room for complacency and fabric specialists at Gore continue to research and develop new solutions to reduce the risk of injury.
For more information, go to www.gore-tex.co.uk