Heat Alert

Image of young child playing in the sand We all enjoy the hot days of summer, but care needs to be taken on days when the temperatures are extreme.

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A Heat Alert is issued when the combination of high heat, high humidity and other weather conditions can be hazardous to your health.
Environment Canada issues humidex advisories when the maximum daily humidex is expected to reach or exceed 40.
If a humidex advisory is issued, then Halton Region Health Department will issue a Heat Alert.
Smog can often accompany extreme heat.
High smog and high heat levels can increase health risks by adding more stress to the body.
A Smog Alert is called when smog conditions reach dangerous levels (Air Quality Index reaches or exceeds 50).

Those especially at risk during heat and smog related weather conditions include:
- Older adults (over the age of 65)
- Infants and young children
- Those with chronic heart or lung disease, including asthma
- People taking certain medications (consult your doctor or pharmacist)
- People who exercise vigorously outdoors (play sports, cyclists, gardeners)
- Outdoor workers (depending upon length or time and exertion levels)
Other risk factors include:
- obesity
- fever
- dehydration
- poor circulation
- sunburn.
Parents, coaches and others supervising children should be aware of the health risks during a heat or smog alert.

If you have the following symptoms of heat-induced illness, seek medical attention right away:

When you exercise or do hard physical work, you breathe harder and bring more dirty air deeper into your lungs. You also breathe through your mouth, bypassing your nose (which acts as a filter).
For those who have heart or lung conditions, exercising outdoors during these extreme weather events could worsen their condition.
If you exercise outdoors during a heat alert, you may:
- Get heat cramps – muscle pains in the legs, arms or abdomen.
- Suffer from headache, nausea, dizziness, confusion, and/or weakness.
- Have a high body temperature that could damage vital organs.

You can avoid heat related illness by doing the following:

Stay out of the hot sun or heat.
If you do go outside, stay in the shade and limit activity to morning/evening.
Where possible, go to air conditioned sites (e.g. malls, community centres).
If you don’t have air conditioning, keep shades drawn and blinds closed.
Fans keep you cool by evaporating sweat. Use fans in or next to your window. But remember that fans alone may not provide enough cooling.
Keep electric lights off or turned down low.
Avoid heavy meals and using your oven.
Take a cool bath or shower periodically or cool down with wet towels.
Avoid strenuous outdoor physical activity.
Reschedule sports practices and jogging times.
Plan ahead – ask for policies to reschedule sports events during heat alerts.
Exercise/workout indoors in an air conditioned area.
Drink lots of water and natural fruit juices (avoid alcohol, coffee, cola).
Wear loose-fitting clothing that allows for evaporation of sweat.
Wear a hat and use sunscreen (of at least SPF 15).
Spend some time near the lake or waterfront where it is cooler.
Never leave children or pets unattended in a car.
Control your pet’s exposure to sun – limit time and provide water and shade.
Call or visit friends/neighbours who are at risk, check on them 2-3 times daily.
Take it easy and rest as much as possible.
Consult your doctor or pharmacist about side effects of medications.

Halton-Peel Heat Alert Totals to Date presented in a bar graph.