Heat stress is mainly an issue during the summer months because of the higher seasonal temperature and higher humidity levels. Direct sun exposure can also be a problem. Employees who work in industries where heat sources are present such as ovens, molten metals, steam, etc. can be exposed to high levels of heat, plus the added effect of the summer heat. Health effects from heat stress can range from discomfort and fatigue, to heat stroke. Transmission of heat to employees can be through several routes of exposure including convection (i.e. air movement), radiation (i.e. radiative heat transfer), and conduction (i.e. body contact).

In Ontario, there are no regulations covering the amount of heat an employee can be exposed to during the workday. However, the American Conference of Governmental Industrial Hygienists (ACGIH) has guidelines that can be used to assess employee heat exposure. These guidelines are a function of physical activity and temperature on the WBGT index.

A heat stress survey can help you to evaluate employee heat exposure. Personal exposure monitoring or area monitoring can be conducted. Heat stress is measured in units of degrees C on the WBGT index.

Where a heat stress survey identifies that employees are exposed to levels of heat that may cause stress, a "Heat Stress Protection Program" should be instituted. Elements of the program include:

	a work/rest regimen
	air conditioned areas
	cold water supply
	proper clothing
	engineering controls
	acclimatization
	work-shift adjustment

Call us today if you believe your company may have a heat stress situation at the workplace. We can conduct a heat stress survey and design a "Heat Stress Protection Program" when needed to control heat stress amongst your employees.