Work in a warm or hot environment coupled with high metabolic loads and/or work in protective clothing can bring about considerable heat strain (e.g. increased heart rate and core body temperature). Acclimation via increasing exposure to work in a hot environment is one potent control used to reduce the level of heat stress and decrease the signs of heat strain. Documented physiological responses of acclimation include improved circulatory efficiency and thermoregulation. Once workers are acclimated to work in the heat, physiological adaptations will persist as long as workers remain in the hot environment. However, workers may be absent from the hot environment due to training, vacation, illness or normal shift change, and some adaptations may be lost requiring some degree of re-acclimation. However, the rate of decay of acclimation is uncertain. In addition, re-acclimation will be dependent on the degree of decay. The basic philosophy of the experimental design is to determine the rate of decay of physiological adaptations of acclimation and the time to re-establish the physiological changes of acclimation. The first goal is to determine loss pattern of acclimation in 7-day increments over a period of approximately 6 weeks. The second goal of the study is to identify the decay pattern from the previous data collected. Based on this information, the loss pattern for 1/3 and 2/3 of total loss of acclimation will be determined. These time periods will be used for the planned decay periods and the time to full re-acclimation will be determined for each. These goals can be accomplished with an experimental design that systematically determines loss of acclimation and time to re-establish acclimation.

Agency
National Institute of Health (NIH)
Institute
National Institute for Occupational Safety and Health (NIOSH)
Type
Small Research Grants (R03)
Project #
1R03OH007836-01
Application #
6575377
Study Section
Safety and Occupational Health Study Section (SOH)
Program Officer
Robison, William
Project Start
2003-09-30
Project End
2005-09-29
Budget Start
2003-09-30
Budget End
2004-09-29
Support Year
1
Fiscal Year
2003
Total Cost
$72,500
Indirect Cost
Name
University of South Florida
Department
Miscellaneous
Type
Schools of Education
DUNS #
069687242
City
Tampa
State
FL
Country
United States
Zip Code
33612
Ashley, Candi D; Ferron, John; Bernard, Thomas E (2015) Loss of heat acclimation and time to re-establish acclimation. J Occup Environ Hyg 12:302-8