Heat Waves

Do you know how to spot the difference between heat cramps, heat stroke, and heat exhaustion? Read our safety tip to find out how to keep cool this summer as the temperature rises.

Anyone can experience heat stress. The health risks are greatest for those over the age of 65, infants and young children, people with chronic illness such as breathing or heart problems, those who work or exercise in the heat, and those who are overweight. Heat illnesses are preventable.

During Heat Waves:

Common symptoms and treatment of hot weather illnesses:

Heat Cramps

Symptoms include sharp pains in the muscles caused by salt imbalance resulting from the failure to replace salt lost with excessive sweat.

Treatment: Move person to cool, shaded area to rest, and apply firm pressure to cramping muscles. Give person two glasses of salty water (mix 5 milliliters of salt to 1 liter of water) at 10 to 15 minute intervals between each glass if cramps persist.

Heat Exhaustion

Symptoms include heavy sweating, weakness, dizziness, headache, diarrhea, muscle cramps, cold and clammy skin, low blood pressure, disorientation and possible vomiting. These are caused by excessive loss of water and salt.

Treatment: Move patient to cool area to rest, provide salty water, and cover person if shivering. The person should rest in bed until recovered. Seek medical attention immediately.

Heat Stroke

Symptoms include a core body temperature greater than 40ºC, complete or partial loss of consciousness, reduced cognitive function and cessation of sweating (hot and dry skin), dilated pupils, and elevated blood pressure. Skin may be flushed at first, later ashen or purplish.

Treatment: Heat stroke is very serious. Call 911 immediately and while waiting for the ambulance, move the person to a cool place and sponge body with cool water while letting the water evaporate to reduce body temperature.

Sun Safety for Children

Your child can sunburn in as little as 15 minutes. During a heat wave, limit outdoor activity to cooler morning and evening hours and never let infants or young children play or sleep in the sun in a playpen, stroller, or carriage.

If out in the sun, limit their exposure time as much as possible and apply sunscreen with an SPF 15 or higher. Pay particular attention to the areas that are most exposed, such as the face, lips, ears, neck, shoulders, back, knees, and the tops of their feet. Apply sunscreen at least 20 minutes before going out in the sun and reapply every two hours or more frequently if your child has been involved in vigorous activity that could potentially remove the product, such as swimming, toweling or excessive sweating.

Don't forget to put a wide-brimmed hat and sunglasses on your child. When deciding on sunglasses, look for a label that says ANSI or CSA approved for sun protection and that are labeled as "UVA and UVB blocking", "100% UVR protection" or "UV 400". They will provide almost complete protection against eye damage from the sun.

Dress children in tight woven, light-weight, light-colored, and loose-fitting clothing, preferably in cotton to absorb sweat. Give small amounts of water frequently.

This safety tip was prepared by Public Safety Canada in collaboration with Environment Canada and Health Canada.

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