Factsheet: Protecting your indoor air from outdoor pollutants

Download the alternative format
(PDF format, 52 Kb, 1 page)

Organization: Health Canada

Date published: November 2020

Poor outdoor air quality can involve many different pollutants, including particulate matter and gases, and can come from many different sources, including industrial and vehicle emissions, road dust, and agriculture, as well as both controlled and uncontrolled burning.

When outdoor air quality is poor, Health Canada recommends that individuals, particularly children, the elderly and those with pre-existing health conditions, such as asthma and heart disease, remain indoors as much as possible. Therefore, while challenging, ensuring good indoor air quality is especially important during periods of poor outdoor air quality.

Here are some strategies to reduce sources of indoor air pollutants:

  • Do not smoke indoors.
  • When possible, limit the use of any combustion source, such as incense, candles, and wood stoves. Consider choosing a low-emission wood stove.
  • Make sure you use cleaning products properly. Some products may emit high levels of volatile organic compounds (VOCs).
  • Install and maintain at least one carbon monoxide alarm in the home located near bedrooms, and preferably one on each floor.
  • Maintain humidity levels between 35 and 50% to avoid mould growth.
  • Avoid using ozone generators, as exposure to ozone can be harmful to your health.
  • Use a vacuum cleaner with a high efficiency particulate air (HEPA) filter that traps small particles. Settled dust can be removed by wiping and wet mopping during a pollution episode.
  • Portable HEPA filtration units may also reduce indoor particulate levels. Filters may have to be changed or replaced more often, depending on use and conditions.

These are some strategies to reduce infiltration of outdoor air pollutants:

  • Keep windows and doors closed, and use air conditioning if the weather is warm.
  • Properly seal windows and doors with weather stripping.
  • Set your heating, ventilation and air conditioning (HVAC) system to recirculate when the outdoor air is poor, and bring in fresh air when the outdoor air has improved.
  • In homes with forced air ventilation, install a high quality air filter to help remove particulate matter from the incoming air.

How do I know if the outdoor air quality is poor?

In order to know the quality of the outdoor air in your community, refer to the Air Quality Health Index (AQHI). The AQHI provides local and real-time information in regards to the quality of outdoor air, and recommends specific advice based on the health risk posed by air pollution levels. Further information on the AQHI, as well as current conditions and forecasts, can be found at www.airhealth.ca.

Where do I go for more information?

To learn more about air quality and health, please visit our website at Air quality and health or contact us at HC.air.SC@canada.ca.

Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: