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Heat Stress Level among Construction Workers.
Aliasghar Farshad1, Saideh Montazer1, Mohammad Reza Monazzam2
11. Occupational Health Research Center, Iran University of Medical Sciences , Tehran, Iran.
Iranian Journal of Public Health
|May 26, 2015
Summary
Construction workers in Iran experienced allowed heat stress levels. Thermal Work Limit (TWL) and Wet Bulb Globe Temperature (WBGT) indices, along with Urine Specific Gravity (USG), were used to assess heat exposure, with TWL showing merit for intervention classification.
Area of Science:
- Occupational Health
- Environmental Science
- Physiology
Background:
- Heat stress poses significant risks to construction workers.
- Assessing heat stress is crucial for worker safety in demanding environments.
- Existing indices require validation for specific climatic conditions.
Purpose of the Study:
- To evaluate heat stress in Iranian construction workers.
- To compare the efficacy of Thermal Work Limit (TWL) and Wet Bulb Globe Temperature (WBGT) indices.
- To assess hydration status using Urine Specific Gravity (USG).
Main Methods:
- A comparative experimental study was conducted in Tehran, Iran.
- Sixty construction workers were divided into sun-exposed and non-exposed groups.
- Measurements included TWL, WBGT, and USG across work shifts over two days.
Main Results:
- Significant differences in TWL, WBGT, and USG were observed between groups (P<0.01).
- Mean WBGT was higher in the exposed group (27.5 ± 1.2 °C) versus control (22.6 ± 0.9 °C).
- Mean TWL was lower in the exposed group (144 ± 9.8 W/m²) versus control (215.8 ± 5.2 W/m²).
Conclusions:
- Construction workers in this study were within allowed heat stress limits.
- TWL, WBGT, and USG measurements were significantly correlated.
- TWL demonstrated advantages over WBGT for classifying heat stress and guiding interventions.
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