Operational and Thermophysiological Needs for Metabolic Heat Dissipation: Ways, Deviations, and Progress

Abstract

The thermophysiological regulation of body temperature is partially or completely inhibited by protection suits especially when several qualities of protection are needed. The result of an insufficient thermophysiological response is heat stress with decreased mental and physical performance of the human being. To get an idea about the amount of heat stress different physiological values are measured: metabolic rate, heat frequency, mean skin and core temperature, sweat rate, psychological performance tests, loss of energy in W/sq cm, etc. This variety of different data demonstrats the difficulty to get an exact picture how much heat stress can be tolerated under different circumstances. Nobody doubts that technical cooling devices are necessary to keep the human performance tolerable and to avoid a collapse that may lead to death: heat reflecting clothes, cooling jackets filled with water or carbon dioxide snow, two-layered protection suit with cool pressurized air, etc. The best solution is the natural one: (1) allow the body to sweat and transport the humidity away to keep the environment as dry as possible to avoid a saturation of humidity surrounding the human body. (2) Clothing must not be close to the body in order to allow circulation of air to get rid of the evaporated sweat (chimney-effect).

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 2002
Accession Number
ADP012420

Entities

People

  • Hans-joachim Knoefel

Tags

Communities of Interest

  • Biomedical

DTIC Thesaurus Topics

  • Air
  • Air Force
  • Aviation Medicine
  • Body Temperature
  • Carbon Dioxide
  • Clothing
  • Compressed Air
  • Hard Copy
  • Heat Energy
  • Human Body
  • Humidity
  • Mobility
  • Motor Skills
  • Performance Tests
  • Protective Clothing
  • Regulations
  • Technical Information Centers

Readers

  • Educational Psychology
  • Exercise and Sports Science.
  • Thermal Physics or Thermal Science.