Breathe Easy: Ventilation

We spend 80-90% of our time indoors, so the air we breathe at home has a big impact on our health and wellbeing.

Exposure to pollutants commonly found in indoor air have been shown to cause a range of health issues, including respiratory illness, cardiac disease, cognitive impairment and cancer.

But don’t worry! As you navigate this story, you’ll see how different activities can impact the quality of the air you breathe.

Whether you live in the city, country, or in-between; an apartment or house; old home or new home - there are simple actions that you can take to improve ventilation and reduce your risks.

Ventilation is the movement of air into or out of homes. 

It can be used to improve indoor air quality by removing pollutants from the home and by bringing in fresh air.

Try the sniff test. When you first enter your home from the outside, it should smell fresh/neutral. If you can smell residual cooking odours, garbage, perfumes or mustiness, you may need better ventilation! 

That includes opening doors and windows to let fresh air in, regularly using bathroom and kitchen exhaust fans to let stale air out and using fans to circulate air in and out of rooms. 

Even if your home smells fresh, if you aren’t regularly opening windows or using bathroom or kitchen fans, you should consider increasing ventilation as a way to improve indoor air quality. 

You are going to need fresh clothes for the weekend, so you decide to tackle that pile of laundry that has been sitting in the basket all week. Maybe THAT’s where that musty odour is coming from?

You empty out the basket and sort it into piles. There is already a load in the machine – Jamie must have put it in this morning. You move it to the dryer so you can start a new load.

Many of our activities like cooking add moisture to the air, which in turn can lead to mould and mildew.

Keep your home well ventilated to keep moisture from building up.

Keep doors between rooms open to allow air to move freely and use the range hood every time you cook. It will help draw out moisture, as well as remove odours from the kitchen.

Did you know that particulate matter (PM), nitrogen dioxide (NO₂) and carbon monoxide (CO) get released in the air when you cook, especially when using a gas stove?

Cooking on the back burner and using the range hood (preferably on high) will help reduce particles and gases by more than 80%. 

So, get into the habit of using your range hood or fan, every time you cook!

Run the bathroom fan while you bathe or shower, and keep it on for at least 15 minutes afterwards to help pull the moist air out of the bathroom and avoid mould issues. 

Don’t have a fan, or need a new one? Look for the EnergyStar logo - you’ll be sure to get one that is energy efficient, and quieter too!

Find certified products using the EnergyStar product finder (note, you’ll be directed to the US website – just select “Canada” as your market.)

As you dry off, you notice some dark spots in the caulking around the tub, and some on the tile grout as well. Looks like mildew.

Better deal with that right away!

You reach under the cabinet for your spray bottle. No need for bleach or harsh chemicals – you made your own solution by dissolving a tablespoon of baking soda into water! You spray it on, scrub the area, then spray it again and let it dry. Done!

Mould and mildew love damp spaces. The longer it's left untreated, the more damage it can do to your home, and the greater the risk to your health, especially for those sensitive to mould. Clean up mould and mildew as soon as you see it.

Many cleaning products can release irritating chemicals. Use non-toxic household cleaners or make your own. To help keep your home free of mould and mildew, common household products such as unscented detergent, vinegar, hydrogen peroxide or baking soda will do the trick!

Carbon monoxide (or CO) has no colour, taste or smell. The best way to protect yourself is to keep all your fuel-burning appliances well maintained, and have at least one certified CO alarm in the home, preferably close to bedrooms.

Want to learn more about ways you can reduce your risks of exposure to CO? Visit our carbon monoxide guide.

As you push open the bedroom door, you hear a welcoming purr.  Your cat Ginger is in her usual spot, curled up on the chair by the window.  She stretches lazily and you go over to give her a scratch.

You notice that the sky outside is a bit hazy. You don’t want to risk triggering your asthma so you check the Weather Network or WeatherCAN app on your phone.

All good!  Thankfully, the AQHI reading is low and there are nothing in the forecast to be concerned about.  You open the window a crack to let the breeze in.

Allowing fresh air into the home is important, but not if the air quality is bad outside. 

The Air Quality Health Index (AQHI) provides local and real-time information, and recommends specific advice based on the health risks posed by air pollution levels in your area. 

Check out the Air Quality Health Index in your area.

Odours can linger in closed rooms. 

Get into the habit of opening windows and leaving inside doors open to let air circulate freely throughout your home when weather and outdoor air quality permits. 

Overhead and stationary fans are another great way to help move air in and out of rooms. 

Avoid using scented candles, incense or air fresheners. They don’t clean the air- they just mask the underlying odours, while releasing dangerous gases such as VOCs and particulate matter.

Building and renovation materials like flooring, paints, varnishes and glues can release gases and other contaminants in the air such as formaldehyde and other volatile organic compounds (VOCs). Off-gassing from new furniture or carpeting can also be hazardous.  

Choose low-VOC products wherever possible, and make sure all potentially hazardous products are sealed, labelled and stored safely.

Keep the area well ventilated by opening up windows and letting fresh air in.

You walk into the living room. Jamie should be home soon so you decide to build a fire in the fireplace while you wait.

You pick out some kindling and a couple of nice dry logs. Oops – almost forgot to open the flue!

Inadequate ventilation of the fireplace can lead to dangerous levels of carbon monoxide. Without proper airflow, this dangerous gas can build up in your home. So, before you light that fire, make sure the damper is open and the chimney is clean.

Have your fireplace inspected annually to make sure it is functioning properly and free of debris such as leaves or nests. Never burn plastics, newspapers or magazines.

Different hobbies like arts and crafts use products that release gases and particles can cause health problems, like shortness of breath, dizziness, or an allergic reaction.  

Check labels and choose low-VOC materials where possible. Keep your workspace well ventilated.

A bit of the glitter has gotten on the carpet, and some sawdust from the logs have made a mess by the fireplace. The place could use a quick clean, so you move all the furniture out of the way and sweep up.

Your efforts are rewarded: under the sofa you find $17 in change, and a cat toy!

Regular cleaning will help reduce the presence of dust, allergens and other particulate matter that can impact your health. 

Make sure to regularly clean out the lint trap to make sure your dryer is ventilating properly. 

Don’t forget to check for lint build-up on the outside vent.

Radon is a radioactive gas that can lead to lung cancer.

For more information on radon and how to test your home, visit Health Canada's Radon information page.

Humidity levels in the home should stay between 30-50%. You can use a hygrometer to measure the level of humidity in the air – they are inexpensive and easily available online and at hardware stores.

Thanks for joining us in this story. As you saw, there are lots of things that impact the air quality of a home, including the number of occupants and their activities. This means that there isn’t a one-size-fits-all solution.

Your best strategy? 

1. Recognize and change the activities that contribute to bad air quality in your home
2. Eliminate sources of pollution in and around your home
3. Improve ventilation

Have questions or want to know more about indoor air quality and your health? Connect with Environmental Health Protection staff at Health Canada, either by phone at 1-833-223-1014, or you can send an email to AIR@hc-sc.gc.ca.

Due to the volume of calls and emails, most requests are responded to within one week.

Please note that Health Canada does not:

• advise on individual situations, including medical and health concerns; For medical problems, questions or concerns, contact your health care provider, e.g., family doctor or public/community health clinic.
• set or enforce regulations for air quality or intervene in local air quality issues
• test air quality or interpret test results; or
• advise on specific brands or models of air quality tests or air purifiers