Working in high temperatures — whether in sunny outdoors or in hot smelting plants — can be dangerous. Canadians working in hot environments, such as mines, agriculture fields, roofs, construction sites and bakeries, are particularly at risk in the summer months.
Many workers may not know that an increase in body temperature of just a few degrees could affect their mental functioning. An increase of a few more degrees can result in serious injury or death. Heat may also be the underlying cause of a workplace accident, a fall or a heart attack.
Heat stress is a buildup of body heat generated either internally (by muscle use) or externally (by the environment) that affects the body's natural cooling system. Without proper precautions, this heat buildup can develop into heat exhaustion or heat stroke, a potentially fatal condition. As the internal heat increases, the worker's body temperature and heart rate rise and the body becomes overwhelmed. When it comes to heat illness, prevention is key.
Tips for employers
Every year, Canadian workers die on the job because of heat-related causes. Employers must manage this risk — evaluate the situation and determine appropriate controls. Depending on the workplace, a heat stress control program may be necessary. Help reduce the risk by arranging work activities that match the employee's physical condition and the temperature.
Provide training. Take time to train the workers on the serious health risks of heat illness, how to avoid it, how to recognize the symptoms and what to do if it happens.
Keep workers cool. Demonstrate the employer’s commitment to worker health by allowing some flexibility in work arrangements during hot conditions. If possible, schedule heavy tasks, and work that requires PPE, for cooler times such as early mornings or evenings. Keep the work area cool or provide air-conditioned rest areas. For workers on duty in the heat, provide plenty of water and encourage them to drink even if they don't feel thirsty, and to take frequent rest breaks.
Tips for workers
Do not expect to tolerate the heat right away. It can take up to two weeks for a person to build up a tolerance for working in hot conditions. Adapt your work and pace to the temperature and how you feel.
Take breaks. A simple but potentially life-saving practice, taking a break to cool off in the shade helps prevent your body from overheating. Look for shade or take breaks in an air-conditioned building or vehicle. If there is no shady or cool place to rest, reduce physical efforts.
Keep cool. Stay out of the sun as much as possible. If the job includes some physically demanding tasks, try to save those for the early morning or late afternoon hours when the sun is less intense. Wear lightweight clothing. The risk of heat illness can be greater when wearing certain types of personal protective equipment. If necessary, consider also wearing a cooling vest to help keep the body temperature down.
Stay hydrated. This is essential. As a general guideline, drink one cup of water every 15 to 20 minutes.
Avoid alcohol and drugs. The effects of heat illness may be worse if drugs or alcohol is ingested. If on medication, read the label or talk to a doctor to understand how it might cause the body to react to the sun and heat.
Recognize the symptoms of heat stress in yourself and your co-workers. These symptoms include rash, cramping, fainting, excessive sweating, headache and dizziness. You may not see or feel the effects so always use the buddy system to monitor one another.
The warning signs of heat exhaustion include heavy sweating, moist, clammy skin, dizziness, nausea, vomiting, headache, muscle cramps, extreme weakness or tiredness, fainting and pale or flushed complexion.
Anyone with these symptoms should be moved to a cool place to rest. Remove or loosen excess clothing (hard hat, boots, shirt, coveralls) and cool the victim with cold packs or wet cloths such as towels or sheets. If they are conscious, give them half a cup of cold water to drink every fifteen minutes.
Heat stroke is one of the most serious types of heat illness. Unless the victim receives quick and appropriate treatment, they can die as a result of heart failure, kidney failure or brain damage caused by excess body heat.
Warning signs may vary but may include red, dry, hot skin (no sweating), a very high body temperature (above 41°C), dizziness or confusion, breathlessness and complete or partial loss of consciousness.
Any person with signs or symptoms of heat stroke is in danger and needs to be hospitalized. Get immediate medical help. Meanwhile, move the victim to a cool place, remove heavy clothing, apply ice packs or cold, wet cloths to the neck, armpits, wrists and ankles, and vigorously fan the body to increase cooling and reduce body temperature.
Heat illness is a serious but easily preventable health risk. By following these basic rules workers can enjoy a safe, healthy summer.
The Canadian Centre for Occupational Health and Safety (CCOHS) is Canada's national resource for the advancement of workplace health and safety. CCOHS promotes the total well being — physical, psychosocial and mental health — of working Canadians by providing information, training, education and management systems and solutions that support health and safety programs and the prevention of injury and illness.