High heat in the summer is an issue at many workplaces

Employers must limit employees’ exposure to high heat even if a workplace has not set an upper limit for acceptable temperatures. Employers have to make sure that the temperature, humidity, airflow and radiating surfaces in working environments do not pose a risk to the health and safety of workers. According to the Occupational Safety and Health Act, employers must minimise the harm caused by heat and cold. Work at temperatures above 28 degrees Celsius is considered to be hot work. Employers must strive to keep temperatures below 28°C by technical means, for example by insulating heat sources or making ventilation more efficient.

If the temperature exceeds 28°C, the length of working cycles has to be limited. Workers can perform light or medium work for 50 minutes per hour at 28–33°C and for 45 minutes per hour in temperatures exceeding 33°C. Employees must be allowed to take breaks in a cooler environment.

For heavy work or very high temperatures, it is necessary to take special protective measures, such as using protective equipment and taking frequent breaks. The primary way for reducing thermal load is technical solutions, such as insulating heat sources and improving ventilation.

For protection against heat:

- If the temperature conditions at your workplace do not comply with recommendations, notify your employer and the occupational safety and health representative. If the employer is unable to reduce the thermal load by technical means, breaks have to be taken regularly.

- You can personally reduce heat stress by wearing light and loose clothing that is appropriate for your work and by drinking enough fluid several times an hour. In physical work, the recommendation is to drink 1–2 dl of water or diluted juice 3 to 4 times every hour. Insufficient hydration may result in dehydration or, in the worst-case scenario, heatstroke. Breaks should be taken in a cool or shaded place if possible.