Humidity:
Understanding humidity and taking the necessary precautions can help prevent the risk of your body overheating and experiencing heat-related illnesses. A humidity inex is used as a measure of perceived heat that results from the combined effect of excessive humidity (moisture in the air) and high temperature. The body attempts to maintain a constant internal temperature of 37° at all times and in hot weather sweat is produced, which cools the body when it evaporates. As the humidity in the air increases, sweat does not evaporate as readily, and stops entirely when the relative humidity reaches about 90%. Under these circumstances, the body temperature rises and may cause illness.
The development of heat related illnesses depends on many factors in addition to air temperature and humidity. Wind speed or air movement, work load, radiant heat sources, and a person’s physical condition are important.

List of Hazards on Heat Stress:
Heat Rash:
Heat rash, or prickly heat, occurs when blocked sweat glands become inflamed. This painful rash reduces the body’s ability to sweat and to tolerate heat.
Heat cramps
Heat cramps are painful spasms of the muscles. The muscles used in doing the work are most susceptible. The spasms are caused by the failure of the body to replace its lost body salts and usually occur after heavy sweating.
Heat exhaustion
Heat exhaustion results when the body loses large amounts of fluid by sweating during work in hot environments. The skin becomes cool and clammy. Symptoms include profuse sweating, weakness, dizziness, nausea, and headaches.
Heat Stroke
Heat stroke is the most serious condition and requires immediate attention; the body temperature becomes very high (even exceeding 41°C). Complete or partial loss of consciousness is possible. Sweating is not a good warning sign of heat stress as there are two types of heat stroke:
“classical” where there is little or no sweating (usually occurs in children, persons who are chronically ill, and the elderly), and
“exertional” where body temperature rises because of strenuous exercise or work and sweating is usually present.
Precaution to be consider on summer season:
Workers should be trained to recognize the signs and symptoms of heat stress and how to avoid them. An emergency action plan which includes procedures for providing affected workers with first aid and medical care should be in place.
Understanding humidity and taking the necessary precautions can help prevent the risk of your body overheating and experiencing heat-related illnesses. A humidity inex is used as a measure of perceived heat that results from the combined effect of excessive humidity (moisture in the air) and high temperature. The body attempts to maintain a constant internal temperature of 37° at all times and in hot weather sweat is produced, which cools the body when it evaporates. As the humidity in the air increases, sweat does not evaporate as readily, and stops entirely when the relative humidity reaches about 90%. Under these circumstances, the body temperature rises and may cause illness.
The development of heat related illnesses depends on many factors in addition to air temperature and humidity. Wind speed or air movement, work load, radiant heat sources, and a person’s physical condition are important.
List of Hazards on Heat Stress:
Heat Rash:
Heat rash, or prickly heat, occurs when blocked sweat glands become inflamed. This painful rash reduces the body’s ability to sweat and to tolerate heat.
Heat cramps
Heat cramps are painful spasms of the muscles. The muscles used in doing the work are most susceptible. The spasms are caused by the failure of the body to replace its lost body salts and usually occur after heavy sweating.
Heat exhaustion
Heat exhaustion results when the body loses large amounts of fluid by sweating during work in hot environments. The skin becomes cool and clammy. Symptoms include profuse sweating, weakness, dizziness, nausea, and headaches.
Heat Stroke
Heat stroke is the most serious condition and requires immediate attention; the body temperature becomes very high (even exceeding 41°C). Complete or partial loss of consciousness is possible. Sweating is not a good warning sign of heat stress as there are two types of heat stroke:
“classical” where there is little or no sweating (usually occurs in children, persons who are chronically ill, and the elderly), and
“exertional” where body temperature rises because of strenuous exercise or work and sweating is usually present.
Precaution to be consider on summer season:
- Monitor environmental conditions and allow self-limiting of exposure when necessary. If this is not possible, adjust work/rest cycles accordingly.
- Avoid sun exposure. Take frequent breaks in a cool or well-ventilated area to get out of the sun and heat.
- Don’t be afraid to sweat. Sweating is the body’s most effective cooling mechanism.
- Take time to acclimatize to new working conditions and temperatures.
- Stay hydrated. Drink plenty of water in hot weather conditions, on average, one litre every hour.
- If possible, postpone strenuous work to a cooler time of day.
- Wear light clothing.
- Consider the use of cooling vests.
Workers should be trained to recognize the signs and symptoms of heat stress and how to avoid them. An emergency action plan which includes procedures for providing affected workers with first aid and medical care should be in place.