Step 1 – Prepare for the heat

  • Tune in regularly to local weather forecasts and alerts so you know when to take extra care.
  • Arrange for regular visits by family members, neighbours or friends during very hot days in case you need help. Visitors can help identify signs of heat illness that could be missed over the phone.*
  • Find ways to keep cool before the hot weather starts. If you have an air conditioner, make sure it works properly. If you have ceiling fans or other fans they can help as long as the humidity isn’t high. Find an air-conditioned spot close by where you can cool off for a few hours on very hot days. This will help you cope with the heat.
  • Have cool drinks in your vehicle and keep your gas tank topped up

Step 2 – Pay close attention to how you – and those around you – feel

  • Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you are caring for someone who has a high body temperature and is either unconscious, confused or has stopped sweating.
  • Watch for symptoms of heat illness, which include:
    • dizziness or fainting
    • nausea or vomiting
    • headache
    • rapid breathing and heartbeat
    • extreme thirst (dry mouth or sticky saliva)
    • decreased urination with unusually dark yellow urine
    • behaviour changes in children (like sleepiness or temper tantrums)
  • If you have any of these symptoms during extreme heat, move to a cool place and drink liquids right away. Water is best.
    • While waiting for help – cool the person right away by:
      • moving them to a cool place, if you can
      • applying cold water to large areas of their skin or clothing
      • fanning the person as much as possible

Step 3 – Stay hydrated

  • Drink plenty of cool liquids (especially water) before you feel thirsty to decrease your risk of dehydration (not having enough fluids in your body). Thirst is not a good indicator of dehydration.
    • Drink water often throughout the day.
    • Keep water nearby when you are at work, school, or out and about by carrying a reusable water bottle. 
    • Drink water before, during and after physical activity.
    • Remember to drink more during hot weather. 
    • Eat more vegetables and fruits as they have a high-water content.

Step 4 – Stay cool

  • Your body is not used to (not acclimatized to) extreme heat at the beginning of the summer. If you are physically active, you are also not acclimatized if you don’t exercise regularly during hot weather.
  • Dress for the weather
    • Wear loose-fitting, light-coloured clothing and a wide-brimmed hat made of breathable fabric.
    • When you buy sunglasses, make sure they provide protection against both UVA and UVB rays.
  • Take a break from the heat
    • If you must do physical activity in extreme heat, take extra breaks, remove gear to let your body cool off and drink lots of water. Don’t expect your usual performance in hot weather. Give your body time to recover after being in the heat.
  • Keep your home cool
    • Make meals that don’t need to be cooked in an oven.
    • Block the sun by closing awnings, curtains or blinds during the day.
    • If safe, open your windows at night to let cooler air into your home.
    • If you have an air conditioner with a thermostat, keep it set to the highest setting that is comfortable (somewhere between 22ºC/72ºF and 26ºC/79ºF). This will reduce your energy costs and provide you with needed relief. If you are using a window air conditioner, cool only one room where you can go for heat relief.
  • If your home is extremely hot
    • Take cool showers or baths until you feel refreshed.
    • Use a fan to help you stay cool and aim the air flow in your direction.**
    • Spend a few hours in a cool place. It could be a tree-shaded area, swimming facility or an air-conditioned spot like a shopping mall, grocery store, or public library.

Step 5 – Avoid exposure to extreme heat when outdoors

  • Sunburned skin loses its sweating efficiency. This makes it harder for your body to regulate its temperature.
  • Never leave people or pets inside a parked vehicle or in direct sunlight.
    • When the outside air temperature is 23ºC/73ºF, the temperature inside a vehicle can be extremely dangerous – more than 50ºC/122ºF.
  • Reschedule or plan outdoor activities during cooler parts of the day.
    • Before heading out, check the Air Quality Health Index  in your area, if available. Air pollution tends to be at higher levels during very hot days.
    • Plan strenuous outdoor activities for cooler days or choose a cooler location like a place with air conditioning or with tree shade.
  • Avoid sun exposure. Find or bring shade when possible
    • Tree-shaded areas can be as much as 5ºC/9ºF cooler than the surrounding area.
    • Shade yourself by wearing a wide-brimmed, breathable hat, or using an umbrella.
    • Wear loose-fitting, light-coloured clothing made of breathable fabric.
    • Wear sunglasses that have UVA and UVB protection.
    • Use a sunscreen with sun protection factor (SPF) 15 or higher and follow the manufacturer’s directions. Don’t use sunscreen on a child less than 6 months old.
  • Remember! Sunscreen will help protect against the sun’s ultraviolet (UV) rays, but not from the heat.

Copied with permission from: Health Canada

Extra Tips

* Arranging for regular visits by family members, neighbours or friends during very hot days is especially important, particularly if you live alone and might need assistance accessing help.

** The City of Toronto12 recommends the following tips for using fans properly:

  • Place fans in or next to a window to bring in the cooler air from outside
  • Do not use fans when the temperature in a room is 34°C or higher as it creates a “convection oven” type of effect. This is especially a concern for older adults and people taking certain medications since their ability to sweat is decreased.

8 Toronto Public Health, Protecting Vulnerable People from Health Impacts of Extreme Heat. Toronto, Ontario: July 2011. Available at: http://www.toronto.ca/health/hphe

9 Climate Change in Canada: Climate Atlas of Canada [Internet]. Climateatlas.ca. 2018 [cited 30 October 2018]. Available from: https://climateatlas.ca/

12 City of Toronto. (2019). Beat the Heat. Retrieved from: https://www.toronto.ca/community-people/health-wellness-care/health-programs-advice/hot-weather/beat-the-heat/