Heat Stressors
There are a variety of effects the human body can exhibit when exposed to heat stress. The results can be mild to life threatening.
Heat Sources and Effects on the Body
The sun is not the only heat source, there are various types of equipment that put out a lot of heat such as welding. The type of clothing and PPE can put further strain on the body’s regulation system. The human body has a temperature regulation system that allows it to cool itself under normal conditions. When it becomes overwhelmed from extreme factors, the body can no longer compensate. Some factors that may impede the process are decrease hydration, humidity, age, clothing, workload, physical health, and acclimatization. Acclimatization is coming accustomed to a new climate or condition and can take anywhere from 5 days to 2 weeks
Heat Stroke
Heat stroke is the most serious heat related illness. Body temperatures can rise above 40°C and mental state can decrease rapidly. Heat stroke develops when all the water and salt available for sweating has been used up. The skin becomes hot, dry, and red. The person may act strange, be weak, confused, have a fast pulse rate, headache, or be dizzy. In later stages the person may become faint or have convulsions. Anyone in this condition should seek medical attention immediately, move to a cool area, remove any excess clothing, fan or spray their body with cool water, and offer sips of salted water.
Heat Exhaustion
Heat exhaustion often occurs when workers become dehydrated due to excess sweating. It occurs when the body’s cooling system cannot keep up with the heat stress. Sweat contains a balance of important fluids and salts. If lost water and salt are not replaced, the body becomes dehydrated. Dizziness and fainting are just two signs of heat exhaustion. Other more common signs include heavy sweating, cool, moist skin, body temperature greater than 38°C, weak pulse, and normal or low blood pressure. The worker may also be tired, weak, clumsy, upset, or confused. They are also usually very thirsty, panting, or may have blurred vision. The worker should be moved to a cooled area, given salted water to drink, and have their clothing loosened. Medical attention is required if the workers condition deteriorates and cooling them down does not work.
Heat Syncope
Heat Syncope often occurs when someone has been standing in a static position in the sun or other hot area for an extended period. Blood pools in the lower part of the body causing individuals to faint. If heat syncope occurs move the person into a seated position, with their legs elevated and have them drink cool, salted water.
Heat Cramps
Heat cramps are painful cramps in the stomach, arms, and legs and can result if heavy sweating drains a person of their body’s salt. Cramps may develop suddenly at work or after work and can be a warning sign for a more serious condition if the heat stress continues. When they occur, have the worker moved to a cooler area and drink salted water.
Heat Rash
Heat rash is inflamed sweat glands that can become infected. The rash may take time to go away, but it does not require medical intervention.
Controls to Prevent Heat Stress
Some controls to limit effects on the body related to heat stress are:
- Air conditioning and cooling fans
- Becoming acclimatized to the working conditions
- Increasing ventilation or shade barriers
- Cooling towels
- Drinking plenty of water to replenish the body and drinking before you feel thirsty
- Eat foods with salt to maintain and replenish salt levels
- Drink fluids with electrolytes such as Gatorade
- Avoid excessive caffeine
- Wear light clothing
- Avoid excessive caffeine
