OSH Answers Fact Sheets

What is measles? Measles is a contagious infectious disease caused by the measles virus. It infects the respiratory tract and spreads throughout the body. Measles can cause severe illness, complications, and death. Although it is most common in children, anyone can become infected.  Measles can be prevented with vaccination. Cases in Canada usually occur when unvaccinated or non-immune people travel abroad to countries where measles is circulating, become infected, and bring measles...

What is crowd management? Crowd management is the process of planning, organizing, and monitoring the gatherings of people, with the goal of maintaining a safe and secure environment.  This document addresses managing occupants or attendees at events or assembly venues. The size of these venues may vary from a small number of people to thousands of people. Examples include fairgrounds, festivals, theatres, concert venues, and sports stadiums. Other events may include gatherings or parades...

What are wildland fires? Wildland fires are any fires that occur in forests, brush, shrubs, and grasslands. They are a natural part of the ecosystem and help maintain forest diversity and health. They may also include prescribed burns and cultural fires.  What causes wildland fires? Wildland fires are most often started by lightning strikes or by human activity. Between early April and late October, many regions of Canada enter wildland fire season. Hundreds of fires may be burning at one...

What is heat stress? "Heat stress" is the "net [overall] heat load to which a worker may be exposed from the combined contributions of metabolic heat, environmental factors, and clothing requirements. As the heat stress approaches human tolerance limits, further increases may lead to unacceptable heat strain and possibility of heat-related disorders." [Reference: 2024 TLVs and BEIs: Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati,...