Workers are sometimes required to work for long periods in hot environments both indoors and outdoors. The body normally cools itself by sweating. During hot weather, especially with high humidity, sweating isn’t enough. Body temperature can rise to dangerous levels if precautions are not taken such as drinking water frequently and resting in the shade or air conditioning. When the human body is unable to maintain a normal temperature, heat illnesses — ranging from heat rash and heat cramps to heat exhaustion and heat stroke — can occur. Heat stroke requires immediate medical attention and can result in death.
Any worker exposed to hot and humid conditions is at risk of heat illness, especially those doing heavy work tasks or using bulky protective clothing and equipment. Some workers might be at greater risk than others if they have not built up a tolerance to hot conditions.