Air pollution: Five things to do when air quality is unhealthy

Wildfires in Canada and Minnesota are currently causing hazardous, hazy air to blanket the Midwest and Northeastern United States. The poor air quality in many areas of Canada and the U.S. is expected to last into the weekend.

So, what should you do if you live in one of these areas with “bad air days”?

How we measure air quality

Air quality measuring sites like the Environmental Protection Agency’s AirNow website measure air quality with the metric of AQI, or “air quality index.”

This index looks at pollutants like particulate matter in the air and ozone.

When AQI reaches 100 or more, that’s an unhealthy rating, especially for people with certain vulnerabilities such as pre-existing respiratory conditions (COPD, asthma, etc.) or who are pregnant, elderly or very young. When AQI reaches 150 or more, air is considered dangerous for everyone, not just those considered vulnerable.

More: The dos and don’ts of home air quality, and why it matters

How to protect yourself when outdoor air reaches hazardous levels

1. Reduce your outdoor activity, especially if it involves exercise or exertion. When you exert yourself, you breathe quicker and deeper, which increases your body's exposure to air pollutants.
2. Check your air filters in your home. Ensure they’re HEPA filters that will effectively filter out particulate matter, and change them regularly.
3. When AQI is above 100, keep your loved ones who are susceptible to more breathing problems indoors when possible.
4. When AQI is above 150, everyone should avoid being outside as much as possible.
5. Consider wearing a mask outdoors to limit the amount of particulate matter that makes it into your lungs. You'll need a tightly fitting N95 mask to filter out this smallest particulate matter – surgical masks, scarves, bandanas and other simple face coverings won't be effective.
6. Keep an eye on the air quality with sites like AirNow.gov.