To advise faculty, staff and students of precautions to follow when their work area reaches about 30°C or 86°F.

Reduce Exposure

  • Postpone nonessential tasks
  • Permit only those persons acclimatized to heat to perform the more strenuous tasks
  • Provide additional persons to perform the tasks keeping in mind that all persons should have the physical capacity to perform the task and that they should be accustomed to the heat
  • Know signs and symptoms of heat stress and what to do in hot weather

Reduce the Heat

  • Open windows in hot work areas
  • Use fans and other methods of creating airflow such as exhaust ventilation or air blowers
  • Wear lighter loose fitting clothing

Rest Breaks

  • Take breaks in a cooler area (outside in the shade or in an air conditioned area)
  • The number and duration of rest breaks is determined by the type of work being done. For example persons working in a warm office would need fewer breaks than those working in a food service kitchen

The Occupational Health Clinics for Ontario Workers recommends using a humidex-based format for determining when work should stop or when to increase the number or duration of work breaks.  

OHCOW's Humidex based heat response plan (PDF)


  • Do not depend on thirst to signal when and how much to drink. Drink plenty of water (about a cup every 20 minutes)

For further information refer to Ontario Ministry of Labour Guideline for Heat Stress