Emergency responders working in encapsulated protective suits may soon be more comfortable, thanks to a new portable cooling system under development by an Oklahoma State University apparel team with input from the U.S. Army Soldier Systems Center in Natick, Mass.

The goal of the project is to improve protective clothing for firefighters, police officers and medical personnel responding to hazardous scenes such as bioterrorist incidents. The researchers have come up with a portable cooling system for work in areas affected by chemical, biological or nuclear weapons that reduces the effects of heat stress on emergency responder performance.

“Today's [weapons of mass destruction] suits are bulky, heavy and hot,” said Donna Branson, professor and head of the Department of Design, Housing and Merchandising at Oklahoma State University. “Heat stress is a serious practical problem for individuals wearing these types of protective clothing while performing critical tasks.”

Branson's team is developing a thinner, lighter and cooler protective system. “We're designing a cooling garment to be worn under a Level A suit that will be interfaced with an innovative cooler unit,” she said.

Some current commercial personal cooling garments use ice pack inserts. Although ice packs are an improvement over no cooling at all, they tend to cool unevenly.

At the core of the OSU system is a technology called adsorptive carbon-based cooling, a new kind of cooling system to solve coolant distribution problems.

“Micro-climate cooling is difficult to accomplish,” Branson said. There are serious technical challenges to be overcome, primarily associated with demanding power requirements.

According to the researchers, the portable, integrated cooling system will include a liquid-circulating garment developed in Natick and powered by a battery capable of supporting a one-hour mission. Average body heat dissipation is pegged at 200 watts in an 80°F environment.

“At this time, we have a prototype garment interfaced with a prototype cooler,” Branson said. “Both prototype components have been extensively tested in our individual laboratories for a variety of tests with promising results. Next, we'll interface the two components and start thermal manikin testing on the whole system.”

The three-year project is just entering its third year. By next spring, Branson plans to have a next-generation system ready for first responder field testing.

“Our ultimate goal is to have the system commercially available for the first responder community,” she said.