Accession Number : ADA310451

Title :   The Effects of a Passive Microclimate Cooling System on Human Thermoregulation in the Heat at Rest.

Descriptive Note : Technical rept. Apr-Aug 90,

Corporate Author : NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA

Personal Author(s) : Heaney, J. H. ; Banta, G. R. ; Bulbulian, R. ; Buono, M. J. ; Burr, R. G.

PDF Url : ADA310451

Report Date : 03 NOV 1995

Pagination or Media Count : 19

Abstract : U.S. Navy personnel are often subjected to extreme thermal environments that may produce marked thermal strain. The purpose of this investigation was to evaluate the effectiveness of a passive microclimate cooling vest in reducing thermal strain during 4-hours of seated rest in a hot environment. Eleven male volunteers completed a 4-hour heat exposure on four consecutive days in a climatic chamber with a thermal environment of 43 deg C dry bulb and 45% relative humidity. The activity level consisted of seated rest. A passive microclimate, cooling garment was worn during two of the heat exposures. Physiological variables measured included heart rate, rectal temperature, mean skin temperature, mean arterial pressure, whole-body sweating rate, forearm blood flow, and skin blood flow. Heart rate, rectal temperature, mean skin temperature, and whole-body sweating rate were significantly- lower in the vest condition compared to the non-vest condition by 17 bpm, 0.3 deg C, 2.6 deg C, and 0.27 L/hr respectively. The remaining variables did not differ by vest condition. The ice vest was effective in reducing thermal strain and use of this ice vest will provide a safer work environment for naval personnel exposed to high-heat conditions by reducing the potential for heat-related injuries.

Descriptors :   *COOLING AND VENTILATING EQUIPMENT, *THERMAL STRESSES, *MICROCLIMATOLOGY, *HEAT STRESS(PHYSIOLOGY), NAVAL PERSONNEL, HUMANS, VOLUNTEERS, RATES, PASSIVE SYSTEMS, ICE, PHYSIOLOGICAL EFFECTS, MALES, RANGE(EXTREMES), HEAT, HEART RATE, HEAT BALANCE, SKIN(ANATOMY), BLOOD CIRCULATION, ARMS(ANATOMY), BLOOD PRESSURE, BODY TEMPERATURE, VESTS, RECTUM.

Subject Categories : Medicine and Medical Research
      Stress Physiology
      Air Condition, Heating, Lighting & Ventilating

Distribution Statement : APPROVED FOR PUBLIC RELEASE