Thermal Liners Perform Better When Dry

The key difference between isodri® Protective Systems and other systems is isodri’s ability to manage moisture in the thermal barrier of your bunker gear. The thermal liner operates like the insulation in your house — it traps air inside of millions of tiny pockets. The trapped air creates a barrier to heat flow. If the air pockets are compressed or filled with moisture, the thermal liner’s ability to block heat is compromised.

Keeping moisture out of the protective envelope takes place on two fronts. The outer shell and moisture barrier keep water from penetrating into your thermal liner from outside sources such as hose water or rain. The other battle is between your thermal liner and moisture generated by perspiration.

How Fibres React to Moisture

When comparing thermal liners, it’s helpful to understand how different fibres react to contact with moisture. Fibres absorb, wick, or shed moisture. Here are the differences:

Absorbing

— Some fibres, such as cotton, draw moisture into their cells and retain it.

Wicking

— Synthetic fibres, such as nylon, draw moisture into their cells and pass it along.

Shedding

— Treated fibres, such as Nomex® with Teflon® F, will not draw moisture into their cells at all. The moisture succumbs to gravity and drops.

Because heated water is unstable and unpredictable, any fibre that absorbs moisture is not suitable for use in a thermal liner.

Fibres that wick do provide some moisture management, however they are not the most advantageous solution. A fire fighter can sweat up to four pounds of water an hour in
the course of normal operations. At this rate of perspiration, there will likely always be water in the thermal barrier.

Every fire fighter knows that heated water is volatile and can release explosive energy in the form of dangerous steam. But water can, and frequently does, cause burn injuries without warning at temperatures well below steam conditions.

isodri® Delivers Optimum Moisture Management

Optimum moisture management comes from a thermal liner that both wicks and sheds water. isodri® Protective Systems feature a face cloth that wicks perspiration away from undergarments. The moisture is channeled to a layer(s) of DuPont™ Nomex® E-89™ treated with Teflon® F. This layer refuses to draw in the moisture and sheds it, allowing the thermal barrier to function as designed. DuPont™ Nomex® E-89™ based thermal liners are made from lightweight and durable nonwoven fabrics available only from DuPont™ using pure virgin fibres.

In addition, isodri® thermal liners using apertured AraFlo® promote higher air permeability than other systems and complement state-of-the-art moisture barriers such as CROSSTECH® Moisture Barriers.

Tough and Durable

There’s even more to isodri® than dry! Each set of isodri® gear is engineered to deliver truly exceptional abrasion resistance, tear strength, colour consistency, and overall
wear life value.

isodri® Protective Systems are available with a wide variety of components, including the latest Fusion™, Advance Ultra™, and PBI® Matrix outer shells; and your choice of CROSSTECH® or Gore RT7100™ moisture barrier.