Accession Number:

ADA276446

Title:

A Review of Microclimate Cooling Systems in the Chemical, Biological, Radiological Environment

Descriptive Note:

Corporate Author:

NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA

Personal Author(s):

Report Date:

1993-09-22

Pagination or Media Count:

29.0

Abstract:

Soldiers may work in hot environments and under conditions posing a biological, chemical, or nuclear threat. Chemical protective overgarments are worn to prevent contact with toxins however, they prevent dissipation of body heat. This review addresses the effectiveness of microclimate cooling systems in alleviating thermal strain in personnel encapsulated in protective overgarments during exertion in the heat. Air, liquid, and passive ice cooling systems are primarily reviewed, but other methodologies are also discussed. Air cooling can increase tolerance time fourfold, but high ambient temperature air cooling may be dangerous. Liquid cooling is effective in reducing heat strain at light to moderate work loads and is beneficial when applied to the thighs during lower- body exercise. Overcooling and discomfort can occur with a liquid-cooled system due to cutaneous vasoconstriction. Liquid-cooled systems are heavy, require excessive maintenance, and tube compression can result in interrupted coolant flow. Air cooling is inefficient compared to liquid cooling because of airs lower specific heat. Ice cooling may only be suitable for short-term work and is generally less effective than either air or liquid cooling although the wearer can move about untethered. The best cooling system design approach may he indicated by consideration of the unique cooling needs of personnel performing specific tasks in various environments. Microclimate cooling CBR Environment.

Subject Categories:

  • Stress Physiology
  • Chemical, Biological and Radiological Warfare
  • Human Factors Engineering and Man Machine Systems

Distribution Statement:

APPROVED FOR PUBLIC RELEASE