A comfortable work environment is the result of a balance between temperature, humidity, and air distribution. Whenever temperature differences exist between two or more objects, heat can be transferred. The net heat transfer is always from the object of the higher temperature to the object of the lower temperature.
The ambient environment is important because it influences the rate at which a person’s body heat is exchanged with the environment and consequently, the ease with which the body maintains a normal temperature. At times, people must work in situations where there are extremes of cold or hot temperatures.
Scope
This section applies to employers that have employees exposed to extreme temperature conditions. Although OSHA doesn’t have requirements regarding temperatures, the General Duty Clause protects workers from recognized hazards in the work place. Understanding temperature hazards can reduce injury, illness, and health problems in the work place.
Regulatory citations
- 29 USC 654 — Duties of employers and employees (including Pub. L. 91–596 “OSH Act of 1970” 5(a)(1), the “General Duty Clause”)
Key definitions
- Heat stress: The body’s reaction to excess heat as a result of overexertion, high external temperatures, and the bodies inability to release heat through blood flow. Heat stress can cause symptoms including:
- Heat disorders: Stroke, mental confusion, delirium, loss of consciousness, convulsions or coma, and hot dry skin which may be red, mottled, or bluish.
- Heat exhaustion: A result of from loss of fluid through sweating when a worker has failed to drink enough fluids or take in enough salt or both.
- Heat cramps: Painful spasms of the muscles, are caused when workers drink large quantities of water but fail to replace their bodies’ salt loss.
- Heat rash: A rash caused by hot and humid environments where sweat is not easily removed from the surface of the skin by evaporation.
- Cold-related stress: The bodies reaction to colder temperatures including but not limited to, low temperatures, high/cool winds, dampness and cold water in the work place. The bodies inability to sustain a safe temperature can cause cold-related stress with symptoms including:
- Trench foot: Tingling and/or itching sensation, burning, pain, and swelling, and blistering to the feet.
- Frostbite: A result of the skin freezing, causing ice crystals to form between cells and draw water from them, which leads to cellular dehydration.
- General hypothermia: The body’s inability to produce heat, causing normal muscular and cerebral functions to be impaired.
Summary of requirements
Cold stress:
- Train employees on cold hazards and prevention.
- Provide engineer controls including radiant heaters.
- Move workers to warmer areas if there is a risk for hypothermia.
- Ask workers to change to dry clothes if their garments are wet.
- Provide blankets and cover employees’ neck and head to block the cold.
- Apply heat packs to employees if they begin suffering from cold stress.
- Instruct employees to remove and place damp shoes in a dry area.
- Ensure that employees suffering from trench foot maintain their feet at an elevated level and avoid walking.
- Monitor workers throughout the day.
Heat stress:
- Train employees on heat hazards and prevention.
- Provide engineer controls such as air conditioners, fans, and other cooling equipment.
- Establish a complete heat illness prevention program.
- Provide training about the hazards leading to heat stress and how to prevent them.
- Provide cool water to workers close to the warm work area. At least one pint of water per hour is needed.
- Modify work schedules and arrange frequent rest periods with water breaks in shaded or air-conditioned areas.
- Gradually increase workloads and allow more frequent breaks for workers new to the heat or those that have been away from work to adapt to working in the heat (acclimatization).
- Designate a responsible person to monitor conditions and protect workers who are at risk of heat stress.
- Consider protective clothing that provides cooling.
