Heatwave Safety: Recognizing and Preventing Heat Exhaustion

Heat exhaustion usually happens when you lose too much water and salt through sweating. It can happen to anyone, even people who are usually active and healthy. Some people just need to be a little more careful, including older adults, babies and young children, outdoor workers, athletes, people without reliable air conditioning, and anyone taking medications that can affect hydration or body temperature. It may build slowly over a few hot hours, or it may come on quickly after exercise, yard work, or even a long walk in the sun.

Too Hot? Here’s What to Watch For.

So, what should you look for? Heavy sweating, weakness, dizziness, headache, nausea, muscle cramps, a racing pulse, cool or clammy skin, or feeling faint can all be signs that the heat is getting to you. Someone may also seem unusually tired, mixed up, or cranky. Think of these signs as your body’s way of saying, “I need to cool down now.” Most of the time, quick action helps. But if someone becomes very confused, passes out, has a very high body temperature, or stops sweating despite the heat, call emergency services right away.

If you think someone may have heat exhaustion, start by getting them somewhere cooler. Move them into the shade, an air-conditioned room, or any spot that is out of the heat. Encourage them to sit or lie down, loosen tight clothing, and sip cool water or an electrolyte drink if they are awake and able to swallow. Cool cloths, a fan, a gentle mist of water, or a cool shower can also help. If they vomit, faint, become confused, have chest pain, or don’t improve within about an hour, it’s best to get medical help.

Stay Cool When the Heat Is On.

The best plan is to stay ahead of the heat. Sip water throughout the day, even before you feel thirsty. If you can, save errands, exercise, gardening, or outdoor chores for the morning or evening, when it’s usually cooler. Choose lightweight, loose-fitting clothes in light colours, and add a wide-brimmed hat and sunscreen if you’ll be outside. And give yourself permission to slow down. Heatwaves are not the time to push through fatigue or squeeze in “just one more thing.”

At home, a few simple habits can make a real difference. Close curtains or blinds during the hottest part of the day, and open windows only when the air outside feels cooler. Fans can help you feel more comfortable, but if your home is getting too hot, consider spending time somewhere air-conditioned, such as a library, community centre, shopping centre, or cooling centre. Local public health updates can also point you toward heat alerts and nearby cooling options.

Staying safe in the heat is also something we can do for one another. During a heatwave, check in on neighbours, friends, and family members who live alone, have limited mobility, or may not have a cool place to go. Never leave children or pets in parked vehicles, even for a quick errand, because the temperature inside a car can climb dangerously fast. If you work, exercise, or play sports outdoors, use a buddy system so someone can spot early signs that the heat is becoming too much.

A holistic approach to heatwave safety comes down to listening to your body, respecting the weather, and looking out for each other. Rest, water, shade, and cooling off are not luxuries during extreme heat—they are simple, practical ways to protect your health. With a little planning and quick action when something feels off, we can move through hot days more safely, more comfortably, and with a lot less stress.