Health Protection

What is heat?

The effect of heat on the body is a result of three factors: humidity level causing 70% of heat stress, sun radiation causing 20% and the air temperature causing 10% of heat stress. Therefore, the humidity level plays the most important role in heat induced stress and illness. This measurement is referred to as the HUMIDEX.

How does heat affect the body?

Generally, humans can control their internal temperature in the heat by sweating. However, under extreme heat and humidity conditions the body cannot keep up and will suffer from heat stress including heat exhaustion and even heat stroke which can be very dangerous. The elderly and children, as well as those with chronic respiratory and heart conditions, are more susceptible to heat induced injury.

Why children are more susceptible to heat?

Children's bodies have greater surface area to body mass ratio, so they absorb more heat on a hot day (and lose heat more rapidly on a cold day). Also, children have considerable lower sweating capacity than adults, so they are less able to lose body heat through sweating and cooling.

When the humidex level approaches 30°C (86°F), please consider the following:

1. Keep doors and windows open, and lights off.
2. If funds are available purchase fans for all classrooms.
3. Remind parents / students to wear light weight and light colored clothing.
4. Remind parents / students to always wear visors, hats, and sunscreen when outside.
5. Allow water bottles at student desks or more frequent water breaks, especially during lunch hours.
6. Where there is air conditioning in libraries or classrooms consider rotating groups of students into those rooms.
7. Consider indoor or modified recesses and lunch hours.
8. Check weather network link www.weatheroffice.ec.gc.ca regarding smog advisories and other weather conditions.
9. Use PA announcements to advise students not to overexert themselves during recess periods.
10. If funds are available create shady areas (build gazebos or plant trees) on the school property.

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Provided courtesy of Health Protection    www.publichealthgreybruce.on.ca

Offices:    Owen Sound 376-9420 or 1-800-263-3456

Walkerton 881-1920