Probability of Hyperthermia in a Hot Environment While Wearing a Liquid Cooling Garment Underneath Firefighters’ Protective Clothing

Details

• Personal Author:
  Aljaroudi AM ; Bhattacharya, Amit ; Quinn TD ; Strauch AL ; Williams WJ ; Yorio P
• Description:
  Firefighters' protective clothing (FPC) can limit human thermoregulation due to limited water vapor permeability and insulation. This study investigated the effect of cooling on the physiological responses and probability of hyperthermia in subjects wearing FPC during exercise in a hot environment. Twelve males participated in this study. A maximal graded treadmill exercise test was performed to measure maximal oxygen uptake (VO2max) and to assess subjects' capacity to perform the assigned exercise. Exercise included treadmill walking at 40% VO2max in warm (30 degrees C) and humid (70% RH) conditions for 40 min while wearing FPC. Subjects participated in two randomly counterbalanced assigned experimental protocols: control (no cooling) and intervention (cooling). The experimental intervention consisted of a cooling garment infused with cooled water (18 degrees C) through silastic tubing sewn into the fabric and worn underneath FPC. Each subject served as their own control and, therefore, completed both the control and intervention of the protocol. A logistic regression model was used to analyze the interaction effect of cooling on the probability of progression to hyperthermia (Tc ≥38 degrees C). Subjects' physiological responses increased during exercise in a warm and humid environment. Active cooling decreased (p < 0.05) the thermal stress thereby reducing the probability of hyperthermia while exercising in hot and humid conditions. The results indicate that when cooling was used each subject, on average, was 91% less likely to reach the lower threshold limit of hyperthermia. Exercise in hot environments while wearing FPC results in significant physiological strain, which may lead to hyperthermia. Utilization of a cooling garment reduced physiological strain and the probability of hyperthermia. [Description provided by NIOSH]
• Subjects:
  Firefighters Heat Stress Disorders Hot Temperature Humidity Occupational Health Personal Protective Equipment Protective Clothing Safety
• Keywords:
  Author Keywords: Continuous Cooling Cooling Systems Fire Fighters Firefighters Heat Stress Hot Environments Hyperthermia Personal Protective Equipment Physiological Response PPE Protective Clothing Thermoregulation Work Physiology

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• ISSN:
  1545-9624
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  District of Columbia ; Ohio ; OSHA Region 3 ; OSHA Region 5 ; OSHA Region 6 ; Pennsylvania ; Texas
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  NPPTL - National Personal Protective Technology Laboratory
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  203-211
• Volume:
  18
• Issue:
  4
• NIOSHTIC Number:
  nn:20062490
• Citation:
  J Occup Environ Hyg 2021 May; 18(4-5):203-211
• Contact Point Address:
  W. Jon Williams, National Personal Protective Technology Laboratory (NPPTL), NIOSH/CDC 626, Cochrans Mill Road, Pittsburgh, PA 15236, USA
• Email:
  aun7@cdc.gov
• Federal Fiscal Year:
  2021
• NORA Priority Area:
  Public Safety
• Performing Organization:
  University of Cincinnati
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Journal of Occupational and Environmental Hygiene
• End Date:
  20260630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:63be1dd40b4a140439d7e62a8be458c0f8352d63b6a8ea35be8f54ed5e9ca3bc66b8e8d2bf3fee00704e1b85c528a3096eb334007c335faed5705c63a0340716
• Download URL:
  https://stacks.cdc.gov/view/cdc/225725/cdc_225725_DS1.pdf
• File Type:
  [PDF - 1.39 MB ]