As temperatures rise to potentially record highs, Worksafe offers some words of warning about heat stress, and offers ways to avoid it and advice on what to do to keep workers safe in extreme heat.
Bodies naturally maintain a temperature between 36 C and 38 C. Sweating cools the body, but this might not be enough for people working in a hot environment. If the body heats up faster than it can cool itself down, a person can experience heat stress that can lead to serious heat disorders and potential injury.
The harder a person works, the more heat the body generates and the more fluids and salt are lost to sweat.
The worker’s physical conditioning also matters, as people who regularly work in hot environments are less prone to heat stress. Poor health, obesity, advanced age and medical conditions can also affect how the body responds to overheating.
Environments where radiant heat from direct or indirect sunlight (such as reflection from pavement) can also be a factor in heat stress.
Workers in a hot environment should be aware of the warning signs of heat stress including excessive sweating, dizziness and nausea.
If heat stress is not recognized and treated early it can lead to heat disorders, which can have serious effects on the body. Symptoms include painful muscle cramps that can lead to heat exhaustion if left untreated. Heat exhaustion symptoms include shallow breathing; increased heart rate; a weak, rapid pulse; cool, pale, clammy skin; sweating; weakness; fatigue; dizziness; headache and nausea; fainting; muscle cramps. All these can lead to heat stroke if left untreated.
Heat stroke symptoms may include hot, dry, flushed skin, no longer sweating, agitation and confusion, decreased level of consciousness and awareness, headache, nausea and vomiting, seizures, increase in breathing rate, irregular pulse, shock and ultimately cardiac arrest.
The most effective way to reduce the risk of heat stress is to eliminate the source of exposure but that’s not always possible.
Examples of key steps that employers can take as part of a heat stress exposure control plan include the following:
- Determine whether it’s necessary to work in hot conditions.
- Monitor environmental conditions.
- Make modifications to facilities, equipment, and processes to reduce heat exposure.
- Assign workers to work in pairs or groups where feasible.
- Change work practices and policies to limit the risk. For example, consider whether work can be done during cooler parts of the day.
- Determine appropriate work-rest cycles. When a worker feels ill, it may be too late.
- Rotate work activities or use additional workers to reduce exposure.
- Establish cooling areas with shade and water.
- Educate and train workers at risk for heat stress. Workers need to know how to recognize signs and symptoms of the early stages of heat stress and what to do in response.
- Ensure there is adequate first aid coverage and that emergency procedures are in place.
In case of an extreme heat emergency, Worksafe advises that employers should consider stopping work if they cannot protect workers from the risk of heat-related illnesses.
