Monitoring heat strain in physically challenging environments
Year: 2012
Type: dissertation
Abstract: Individuals working in physically demanding occupations can experience high levels of heat strain due to the physical demands of the job, harsh environmental conditions and/or the wearing of personnel protective equipment (PPE). The ability to monitor body core temperature (Tc) could reduce the risk of heat illness. The main purpose of this thesis was to examine non-invasive methods of Tc measurement. Studies 1, 2 and 3 investigated the validity of insulated skin temperature (Tis) as a non-invasive measure of Tc, in emergency service (ES) and military personnel. In Study 1, a model including Tis and micro-climate temperature (Tmc) was developed to predict rectal temperature (Tre) for ES personnel wearing PPE. The resulting standard error of the estimate (SEE=0.20 °C) was within the a-priori pre-defined SEE limit (0.20 °C), providing encouragement for the further investigation of Tis as a surrogate measure of Tc. Studies 2 and 3 sought to determine the validity of Tis in predicting Tre in military personnel, wearing PPE in temperate conditions (Study 2) and in a desert environment (Study 3). Although the SEE was outside the acceptable SEE in Study 2 (0.22 °C), the sensitivity (97 %) for predicting Tre values over 38.5 °C provided scope for a military application for Tis to predict Tc. In Study 3, Tis could not predict Tre in a desert environment, with simulated solar radiation directly affecting Tis and invalidating the prediction (SEE = 0.29 °C). Study 4 involved a series of experiments performed under six conditions in a thermal chamber with two clothing types, to determine whether the addition of other physiological and/or environmental factors might improve the prediction of Tre. A model including Tis and Tmc resulted in an SEE of 0.26 °C; with heart rate (HR) and work significantly reducing the SEE (0.23 °C) (p
Author: Victoria L. Richmond
Language: English
Subfield: Physiology (medical)
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W788837891