title: Relationship of Environmental, Physiological, and Perceptual Heat Stress Indices in Iranian Men.
abstract: BACKGROUND
  Heat stress is a known occupational hazard, which cause reduced exercise capacity. The purpose of this study was to evaluate the relationship among environmental, physiological, and perceptual heat stress indices in Iranian men.
  
  
  METHODS
  This analytical study was carried out on 24 healthy men (age 23.34 ± 1.64 years) with normal body weight (body mass indices 21-25 kg/m(2)) in low workload for 120 min under hot climates (22-32°C, 40% relative humidity). Physiological strain index (PSI), wet-bulb globe temperature (WBGT), oral temperature, heart rate (HR), and heat strain score index (HSSI) questionnaires were simultaneous measurements taken at any 5 min during the exposure and resting state the initial measurements.
  
  
  RESULTS
  The results showed that the range of WBGT index was 20.47-31.40°C. Significant correlation were found among WBGT and HSSI (r = 0.995), PSI (r = 0.990), oral temperature (r = 0.991), and HR (r = 0.972) indices. Also, significant correlation were found among HSSI and oral temperature (r = 0.983), HR (r = 0.978), and PSI (r = 0.987).
  
  
  CONCLUSIONS
  The results have shown that simultaneous with the increase in valid indices of heat stress such as WBGT and PSI indices, the amount of HSSI has also increased with high power. Therefore, when there is no access to a reliable heat stress method such as WBGT, or PSI indices, HSSI, an observative and subjective heat strain method, can be used as a simple, fast in least 5 min, and inexpensive for evaluating the heat strain in Iranian men.
authors.affiliation: Department of Occupational Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Peymaneh
authors.initials: P
authors.lastname: Habibi
authors.affiliation: Department of Engineering Occupational Health, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Momeni
authors.affiliation: Department of Occupational Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Habibollah
authors.initials: H
authors.lastname: Dehghan
keywords: Heat strain score index; physiological strain index; wet-bulb globe temperature