Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments
Abstract
1. Introduction
2. Methods and Materials
2.1. Experimental Equipment
2.2. Participants
2.3. Experimental Program
- (1)
- Investigating the effects of different temperatures (23 ± 0.2 °C, 32 ± 0.2 °C, and 38 ± 0.2 °C) in a high-humidity (RH 75 ± 5%) environment on the physiological parameters of individuals wearing shielding clothing.
- (2)
- (Investigating the effects of different humidity levels (RH 30 ± 5%, RH 50 ± 5%, and RH 75 ± 5%) in a high-temperature (38 ± 0.2 °C) environment on the physiological parameters of individuals wearing shielding clothing.
- (3)
- Investigating the changes in physiological parameters of individuals wearing shielding clothing and regular work attire (e.g., electricians’ typical short-sleeve shirts and long pants) under high-temperature and high-humidity conditions (38 ± 0.2 °C, RH 75 ± 5%).
2.4. Experimental Procedure
2.5. Parameter Measurement
2.6. Statistical Analysis
3. Results
3.1. Core Temperature
3.2. Skin Temperature
3.3. Thermal Sensation
3.4. Sweat, Heart Rate and Blood Oxygen
3.5. Error Rate and Response Time of Cognitive Tests
3.6. Variation in Physiological Parameters of the Human Body Under Different Clothing Conditions
4. Discussion
4.1. Effect of Different Temperatures and Humidity on Body Temperature
4.2. Effect of Different Temperature and Humidity on Physiological Responses
4.3. Effects of Different Temperatures and Humidity on Cognitive Performance
4.4. Limitations and Future Study
5. Conclusions
- (1)
- With the increase in temperature and humidity, the core temperature, heart rate, and thermal sensation scores of participants wearing high-voltage-shielding clothing significantly increased, and were higher compared to participants wearing standard workwear. In cognitive testing, high temperature and humidity conditions significantly reduce task accuracy and response speed. Moreover, more complex tasks exhibit even more significant negative effects.
- (2)
- A heat sensation prediction model for live-line workers based on environmental temperature under high humidity conditions was established to predict human heat sensation through environmental temperature. In the neutral heat sensation range (−0.5~+0.5), the environmental temperature should be within the range of 20.8–25.8 °C.
- (3)
- Another prediction model for heat sensation is based on the average skin temperature under high humidity, aimed at predicting the average skin temperature through human heat sensation. In the neutral heat sensation range (−0.5~+0.5), the average skin temperature should fall within the range of 33.4–34.1 °C.
- (4)
- The shielding clothing significantly inhibits the heat dissipation of the participants, leading to increased heat accumulation within the body compared to normal work clothing. Consequently, live-line workers face higher physiological and cognitive burdens. Therefore, effective cooling measures are urgently needed to ensure their occupational safety and work efficiency. The results of this study provide a theoretical basis for the development of personal protective equipment for live-line workers.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Ambient Temperature | Relative Humidity | |||||
---|---|---|---|---|---|---|
RH 75% | 38 °C | |||||
Experimental conditions | 23 °C | 32 °C | 38 °C | RH 30% | RH 50% | RH 75% |
Average skin temperature (°C) | 34.8 | 35.6 | 36.8 | 36.1 | 36.4 | 36.8 |
Standard deviation (°C) | ±1.91 | ±1.23 | ±0.92 | ±1.12 | ±0.99 | ±0.92 |
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Wang, S.; Gui, X.; Ding, L. Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments. Int. J. Environ. Res. Public Health 2025, 22, 387. https://doi.org/10.3390/ijerph22030387
Wang S, Gui X, Ding L. Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments. International Journal of Environmental Research and Public Health. 2025; 22(3):387. https://doi.org/10.3390/ijerph22030387
Chicago/Turabian StyleWang, Shengwei, Xiaohong Gui, and Li Ding. 2025. "Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments" International Journal of Environmental Research and Public Health 22, no. 3: 387. https://doi.org/10.3390/ijerph22030387
APA StyleWang, S., Gui, X., & Ding, L. (2025). Thermophysiology and Cognitive Performance of Live-Line Workers in High-Temperature and High-Humidity Environments. International Journal of Environmental Research and Public Health, 22(3), 387. https://doi.org/10.3390/ijerph22030387