Accession Number:

ADA209089

Title:

Human Biophysical Evaluation of a Permeable Hood Attached to a Chemical Protective Overgarment

Descriptive Note:

Corporate Author:

ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA

Report Date:

1989-04-01

Pagination or Media Count:

28.0

Abstract:

This report focuses on the physiological and biophysical evaluation of a prototype 70-mil permeable hood integrated into the standard 90-mil chemical protective overgarment and its potential in reducing heat strain during continuous exercise. Each of 14 CB-trained Marines in two groups of seven did treadmill exercise heat production, M470W in six randomized environmental sequences ambient air temperature Ta32 deg C80 rhV1 ms and 5 ms, 35 deg C50 rhV1 ms and 5 ms, and 43 deg C20 rhV1 ms and 5 ms. Each group used a similar uniform configuration each day until completion of the above environmental exposures, then altered the uniform configuration for additional runs. Uniform configurations were permeable attached hood integrated to 90-mil standard overgarment OG in the closed configuration with underwear and MX-40 respiratory mask, P-40 standard butyl rubber hood with OG and either the MX-40, B-40 or the M17A respiratory mask B-17. In general, use of a 70-mil permeable hood integrated hood integrated to a standard overgarment gave no significant advantages compared to a standard OG in reduction of heat strain, improvement in vapor permeation to a given clo insulation and extension of endurance times. Although carbon-lined hoods offer optimal chemical protection for the head region, the use of a butyl hood with the M-40 mask suggests a preferable heat transfer option because of the reduced thickness of the hood about 9 times less than the permeable hood which offers an augmented imclo with high wind speeds.

Subject Categories:

  • Stress Physiology
  • Chemical, Biological and Radiological Warfare
  • Protective Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE