Work in high temperatures and protective measures

Updated: 2022-07-22
Basics on high temperature 
High-temperature weather in China refers to days when the highest temperature reaches above 35 ℃. China's meteorological authorities stipulate that if the high-temperature weather lasts for more than three days, it can be called a heat wave.
 
In the field of occupational health, high-temperature work refers to working in an environment where the average Wet Bulb-Globe Temperature (WBGT) index is ≥ 25 ℃. WBGT is a basic parameter for comprehensive evaluation of the heat load on the human body, and its unit of measurement is ℃.
 
Types of high-temperature work
Type 1: Work in high temperature and strong thermal radiation, such as metallurgy, ceramics production, glass-making and casting.
Type 2: Work in high temperature and high humidity, such as textile work, printing and dyeing, as well as downhole operation, where the relative humidity can reach 80% - 90%.
Type 3: Outdoor work in summer. This includes agricultural labor, field investigation, open-air loading and unloading, construction, takeout delivery, environmental sanitation work and military training. In addition to high temperature, the work is often accompanied by thermal radiation from the sun and the ground, so the workers may be exposed to a higher temperature.
 
Protective measures for high-temperature work
For employers:
1.Establish and improve the working system of heatstroke prevention, take effective measures to strengthen the protection of workers in high-temperature environment, and ensure their safety.
2.Arrange the production site reasonably, improve the production and operation process, and adopt heat insulation, ventilation and cooling measures to ensure that the workplace meets the requirements of national occupational health standards.
3.Pregnant and underage workers should not be engaged in outdoor work during hot weather above 35 ℃ or work in any environment where the temperature is above 33 ℃.
4.Adopt flexible working hours, rotation of work, increase the rest time of workers in high-temperature working environments and reduce workloads during high-temperature periods.
5.Adjust working hours according to the forecast temperature released by the meteorological authorities at or above the prefecture level for the day:
(1) If the highest temperature of the day reaches above 40 ℃, outdoor work should be suspended;
(2) When the highest temperature reaches 37 ℃-40 ℃, employers should arrange workers to work outdoors for a total of no more than six hours throughout the day, and no outdoor work should be arranged during the three hours when the temperature is  the highest;
(3) When the highest temperature reaches 35 ℃-37 ℃, employers need to shorten the continuous working hours, and should not arrange outdoor workers to work overtime. 
6. Provide sufficient cooling drinks and necessary heatstroke prevention medicine, for which money or other goods cannot be distributed as substitutes. If any worker is found to have heatstroke symptoms, the employer should to take treatment measures immediately, and send the worker to a hospital in serious cases.
 
For employees:
1.Get enough sleep and keep a good work-life balance. 
People who engage in high-temperature work should reduce the time of outdoor operation in hot weather and take with them heatstroke prevention medicine, electrolyte drinks or drinking water.
2.When symptoms like dizziness, nausea, confusion, or shortness of breath occur, they should immediately move to a cool place to rest, and drink some cold water to cool down.
3.They need to drink light salt water from time to time during working hours. 
Intake of drinking water can be varied according to working intensity and perspiration. When the amount of sweating is more than 3 L/ day, electrolyte carbohydrate drinks should be supplemented. 
Increase the intake of vegetables and fruits to supplement the vitamins lost in sweat.