And even if you don’t feel any discomfort on your run, it doesn’t mean there’s no harm being done. The pollutants can have long-term effects such as reduced lung function, increased risk of respiratory infections and can be linked to countless other health issues.

Canada had some of the worst air quality in North America on Tuesday morning according to waqi.info, the website for the World Air Quality Index project. See how your community ranks.

With various air quality indexes available, and as wildfire smoke becomes an increasing health risk, here’s what often goes into the decision to play sports or not — and how to make sense of air quality indexes when making your own decision.

The poor air quality that has blanketed swaths of central and Western Canada is not only infiltrating the lungs, but also distressing the mind.

Unhealthy air quality is forecast, with periods of Very Unhealthy air quality possible for several hours. Folks should expect to see and smell smoke, and Air Quality Alerts are in effect. Conditions will improve slightly tonight through Sunday.

The heat warning issued last Friday for the Ottawa-Gatineau region should last until Thursday night, according to Environment Canada. Special air quality statements also linger Tuesday in western Quebec.