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Extreme Heat

Extreme temperatures and high humidity pose a significant health risk to Ontarians. Anyone can suffer heat-related illness when their bodies are unable to properly cool. It's important to be aware of who is at greatest risk and what actions can be taken to prevent a heat-related illness or death.

Are You at Risk?

During a heat wave, everyone is at risk, but some groups are more vulnerable than others. They include:

Please see the Ministry of Labour's Website for further advice

Health Risks of Extreme Heat: Know When to Get Help

You can become ill when you are exposed to too much heat, especially if you are doing too much for your age and physical condition.

Adverse health effects that can occur as a direct result of exposure to excessive heat include:

Increases in other health problems can also be seen, especially for those with other chronic medical conditions such as heart conditions.

Consult your physician, a healthcare provider or call Telehealth Ontario (1-866-797-0000 or TTY at 1-877-797-0007) if you experience any of the above symptoms. Call 911 or your local emergency number immediately if you are caring for a someone, such as a neighbour, who has a high body temperature and is either unconscious, confused or has stopped sweating.

Things You Can Do to Protect Yourself

Prepare for the heat in advance

Protect your health during extreme heat

Watch for symptoms of heat illness:

If you have any of these symptoms during extreme heat, immediately move to a cool place and drink liquids. Water is best.

Stay hydrated:

How to stay cool

Dress for the weather

Take a break from the heat

Keep your home cool

If your home is extremely hot

Avoid exposure to extreme heat when outdoors

Find or bring shade to avoid being exposed to the sun

Check up on friends, family and/or neighbours regularly who may be at high risk during a heat event

Do not leave people or pets in parked vehicles as they can get very hot!

Contact your local public health unit for more information.

Useful Heat-Related Links:

For More Information

Call ServiceOntario, Infoline at 1-866-532-3161
In Toronto, 416-314-5518
TTY 1-800-387-5559
In Toronto, TTY 416-327-4282
Hours of operation : 8:30am - 5:00pm