Environment Canada has been issuing heat warnings… Quebec construction workers halted a job on a hospital for a day … some city pools are extending their hours and community centres are offering ‘cool places’ where people can take a break.
A heat dome from the Midwest of the United States recently brought scorching hot temperatures to much of Canada, with daytime highs hitting a humidex rating of around 40. Environment Canada uses humidex ratings to inform the general public when conditions of heat and humidity are possibly uncomfortable. When the humidex rating range is 40-45, it’s very uncomfortable and you should avoid exertion. Above 45, conditions are considered dangerous.
The agency issues heat warnings when it’s concerned about those who are most at risk from heat. These include very young children, the elderly and those with chronic diseases. In the worst case scenario, people can die.
If you are an employer, you have a legal obligation under Occupational Health and Safety Regulations to take every reasonable precaution to protect your workers from the heat. This includes developing policies and procedures to protect employees who work in surroundings that are hot due to processes or the weather.
Heat-related conditions can occur in many work environments, but particularly at risk are construction workers and others who work outdoors, as well as employees in kitchens, bakeries, boiler plants, smelters, foundries and those who work with heavy equipment.
For outdoor workers, direct sunlight is the main source of heat. In mines, geothermal gradients and equipment contribute to heat exposure.
You can’t predict heat illnesses by the temperature on the thermometer. That only measures air temperature. To get an accurate view of the heat load, also consider:
The two most common heat-related conditions are heat stroke and heat exhaustion. Here are their symptoms and treatments.
This is the most serious heat-related health problem for workers. Signs include:
|High body temperature (usually higher than 40C)||Lack of sweating, although with exertional heat stroke there may be profuse sweating|
|Red, hot and dry skin||Nausea or vomiting|
|Rapid heartbeat||Rapid shallow breathing|
|Confusion, disorientation or staggering||Seizures|
|Dizziness or light-headedness||Muscle weakness or cramps|
Treatment: Immediate medical attention is required. Victims of heat stroke can die unless treated promptly. After calling for medical help, Health Canada recommends the victim be moved to a cool area. Soak clothing with cool water and fan vigorously to increase cooling. Prompt first aid can prevent permanent injury to the brain and other organs.
This results from loss of fluid through sweating when a worker has failed to drink enough fluids or take in enough salt. The worker still sweats but experiences extreme weakness or fatigue, giddiness, nausea or headache. The skin is clammy and moist, the complexion pale or flushed, and the body temperature normal or slightly higher.
Treatment: The victim should rest in a cool place and drink an electrolyte solution (a beverage used to quickly restore potassium, calcium and magnesium salts). In severe cases, victims vomit or lose consciousness and require medical assistance.
For both of these conditions, prevention is critical. Here are 5 tips to help keep your workers from suffering in the heat:
1. Provide engineering controls at points of high heat production, such as general ventilation and spot cooling by local exhaust ventilation. Shielding is required as protection from radiant heat sources. Evaporative cooling, mechanical refrigeration and cooling fans can also reduce heat. Modifying equipment, using power tools to reduce manual labor, eliminating steam leaks and wearing protective clothing can also help.
2. Provide plenty of drinking water — at least a quart per worker per hour. Train first aid personnel to recognize and treat heat-related disorders and make the names of trained staff members known to all workers. Employers should also consider an individual worker’s physical condition when determining his or her fitness for working in hot environments. Older and obese workers as well as those on some medications are at greater risk.
3. Alternate work and rest periods with longer rest periods in a cool area. Whenever possible, heavy work should be scheduled during the cooler parts of the day. Train supervisors to detect early signs of heat stress and permit workers to interrupt work if they’re extremely uncomfortable.
4. Acclimate employees to the heat through short exposures followed by longer periods in the hot environment. New employees and workers returning from an absence of two weeks or more should be allowed to acclimate for five days. This should begin with 50% of the normal workload and time exposure the first day, gradually building up to 100% on the fifth day.
5. Keep a first aid kit handy. Stock electrolyte drinks and ice packs, which need no refrigeration and become cold when the cylinder within the pack is broken. Also keep emergency medical numbers.
Educate workers so they’re aware of the need to replace fluids and salt lost through sweating. Make sure they recognize symptoms of dehydration, exhaustion, fainting, heat cramps, salt deficiency, heat exhaustion and heat stroke. And encourage workers to look out for each other in the sweltering heat.
Stay Cool Away from Work
It’s just as important to avoid the heat at home as it is at work.
Here are some tips:
And remember, never leave children or pets alone in closed vehicles. Temperatures in a car can become life threatening within minutes.