Chem-Bio Protective Garments: Making Them Lighter, Tougher.

• Author: Tiron, Roxana
• Position: Joint Service Lightweight Integrated Suit Technology

Researchers at the U.S. Army Soldier and Biological Chemical Command in Natick, Mass., ate working on new technologies that, in the distant future, could provide an alternative to the current carbon-based chemical, biological protective suit, the JSLIST (Joint Service Lightweight Integrated Suit Technology).

All military services have used JSLIST since 1997. It replaced the old battledress overgarment (BDO).

Natick project engineer George Costas said that one of the most promising technologies for future protective garments is the selectively permeable membrane.

JSLIST is today's suit of choice by all the military services, Costas explained. "For the next 10 years, they will stay with the design, and all the changes made will be in the fabric." The JSLIST overgarment is a universal, lightweight, two-piece, front-opening suit that can be worn as an overgarment or as a primary uniform over underwear. It has an integral hood, bellows-type sockets, high-waist trousers, adjustable suspenders, adjustable waistband and a waist-length jacket that enhances system comfort, improves system acceptance and maximizes compatibility with the individual user equipment.

Apart from the integral hood, on the waist-long coat, a flap fastened with Velcro covers the zipper. The sleeves also have Velcro wrist-closure adjustment tabs, and the left sleeve has an outside expandable pocket with flap.

The JSLIST liner consists of a non-woven front, laminated to activate carbon spheres and bonded to a knitted back that absorbs chemical agents. Previously, the BDO liner consisted of charcoal-impregnated polyurethane foam and nylon tricot laminate. The BDO foam deteriorated as the soldiers rubbed against it, and that could become messy.

The durability of the JSLIST is 45 days, compared to 22 days for the BDO. While the old suit was not washable, the JSLIST can be washed six times. Costas said the suit nor only feels a lot cooler, but it is one pound lighter than the BDO, and when packaged, it is 60 percent less bulky.

But Gene Wilusz, a developer of the selective permeable membrane, explained that a suit that uses the membrane system, instead of charcoal, is actually half the weight of the current JSLIST.

"Quite a lot of charcoal is needed to provide the necessary protection and that results in a suit that is heavier and builder than ideal," said Wilusz. "Activated charcoal has worked very well so far as a universal absorbent, but we are trying to reduce the dependence on...