Final answer:
Controlled products exempt from WHMIS include those regulated under the Pest Control Products Act, such as pesticides, due to their specific and alternate regulatory framework. This ensures proper handling and safety measures are in place separately from WHMIS directives.
Step-by-step explanation:
A controlled product which is exempt from WHMIS (Workplace Hazardous Materials Information System) would be materials regulated under the Pest Control Products Act. The rationale behind this is that specific legislation like the Pest Control Products Act already regulates these substances, providing a framework for their safe handling, use, and disposal. Products such as pesticides, herbicides, and insecticides fall into this category and have specific guidelines separate from WHMIS.
The WHMIS system is designed to provide information on hazardous products used in the workplace in Canada. It uses classifications, labels, and safety data sheets (SDS) to communicate danger. However, items like pesticides are governed by separate regulations due to their specialized nature and the public's as well as professionals' widespread use of them.
For example, a can of pesticide with a label warning "Store only at temperatures below 120 °F (48.8 °C). Do not incinerate." indicates that pesticides need to be stored safely to prevent decomposition or combustion that could lead to health risks or environmental harm. In terms of physical chemistry, this type of warning is related to the concept of supercritical fluids, as excessive temperature can create conditions where the substance exceeds its critical temperature and has properties of both liquid and gas, harbouring potential risks.