Indoor Air

It is possible for the air in our houses (indoor air) to contain chemicals that can be harmful and affect our health. In the winter time we spend so much time in our houses, which are sealed up to protect us from the weather, that it is possible for our indoor air to get stale and build up with unwanted substances. These can include tobacco smoke, dust particles, mould spores and other chemicals found in carpet, plywood, paints, glue, and ceiling tile.

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What are the possible health effects?

Some possible health effects from this stale indoor air can include things like:

  • wheezing
  • coughing
  • sneezing
  • sore eye, runny nose, and scratchy throat
  • asthma attacks

However, there are things you can do to avoid or remove these chemicals from the air that you and your family breathe. Here are some other simple steps for maintaining good indoor air quality and minimizing these health risks.

Tips - What can you do?

One of the best and easiest ways to protect the air in your home is through adequate ventilation. This will remove stale indoor air and reduce the amount of pollution inside your home.

  • Use kitchen and bathroom exhaust fans if you have them.
  • Use and maintain your ventilation system according to manufacturer guidelines. a
  • Air out your house from time to time by briefly opening windows and doors when weather permits.

Even small actions--like taking off your shoes or boots when you come inside or changing out of work clothes when you get home--may reduce the chances of letting dirt that may contain various chemicals into your home. These habits are even more important if you work in or travel through areas where you might come into contact with products or materials that pose a health risk.

1 - Tobacco Smoke

One of the biggest problems in many of our homes is tobacco smoke which can pass through cracks under and around doors, so no place in your home or car is safe from tobacco smoke. Toxic chemicals found in tobacco smoke can also stick around even after the smoker has put out the cigarette, cigar, or pipe. This is called third-hand smoke.

Why are we concerned?

Chemicals from third-hand smoke can get trapped in hair, skin, fabric, carpet, furniture, and even toys. It builds up over time and each time another cigarette is lit, more smoke gets trapped and gets into people's lungs and bodies.

Tips - What can you do?

  • Make sure your home and car are as smoke free as possible.
  • Protect yourself and your family from cigarette smoke exposure, and ask those who smoke to smoke outdoors well away from doors and windows of your home.
  • Install a smoke-detector in your home.

2 - Mould

Mould is a type of fungus that comes in a variety of colours and can grow in damp areas inside your home. Mould grows where there is too much humidity from water leaks, cooking, showering, flooding, etc. It can grow on wood, paper, fabrics, drywall, insulation, inside walls or above ceiling tiles. When mould finds a damp place to grow, it can contribute to poor indoor air quality.

Since mould needs moisture to grow, reducing moisture in the air and on surfaces in your home is the best way to reduce potential health risks from moulds.

Why are we concerned?

  • When moulds are growing inside the home, there may be health concerns. Moulds release chemicals and spores. The health effects of mould can range from being insignificant to causing allergic reactions and illness.
  • Pregnant women, infants, the elderly and those with health problems, such as respiratory disease or a weakened immune system, are more at risk when exposed to mould. Consult your health care provider if you believe there is someone who may be at risk

Tips - What can you do?

  • The problem starts when mould grows inside the home. Be sure to inspect your homes for signs of mould.

  • Sometimes moulds are hidden and cannot be seen. A musty or earthy smell often indicates the presence of moulds. But a smell may not be present for all moulds. Even when you don't notice a smell, wet spots, dampness or evidence of a water leak are indications of moisture problems and mould may follow.

  • Keep the home dry.

  • Find and fix water leaks.

  • Instead of leaving clothes on the floor, install hooks so you can hang them to dry.

  • Raise your bed off the floor to let air circulate under the mattress.

  • If you discover mould on hard surfaces in your home:

    • Clean up small areas of mould with soapy water and dry the surface completely. You can clean up "small areas" of mould (fewer than three patches, each smaller than a square meter) yourself. The minimum protective wear needed :

      • Safety glasses or goggles.

      • A disposable dust mask.

      • Household rubber gloves.

    • Infants and other family members with asthma, allergies or other health problems should not be in the work area or adjacent room during the cleaning.

  • If your home has them, turn on fans that vent to the outdoors.

  • Get help from an appropriate authority (such as your community or hamlet) when the mould covers areas larger than one square meter.

3 - Dust and Dust Mites

House dust mites are found in most homes. Dust mites are so small they are not visible to the human eye. They live in beds, carpets, furniture, pillows and blankets. Reducing dust and dust mites in your home will help reduce irritants, which can cause allergic reactions and aggravate asthma and other breathing problems.

Why are we concerned?

The concern about dust mites is that some people are allergic to them. Symptoms associated with dust mite allergies include sneezing, itchy, watery eyes, nasal stuffiness, runny nose, stuffy ears, respiratory problems, eczema and (in severe cases) asthma. Many people notice these symptoms when they stir dust during cleaning activities.

Tips – What can you do?

  • Dust your home regularly from top to bottom. Use a damp cloth to avoid raising dust into the air.
  • Reduce clutter so dust will have fewer places to settle and to make cleaning easier.
  • Vacuum carpets and any fabric-covered furniture to reduce dust build-up. Vacuuming will also remove pet dander, which may cause allergic reactions in some people. Where possible, keep pets out of bedrooms and off furniture to reduce your family's exposure to pet dander.
  • Vacuum mattresses to minimize dust mites. Wash sheets regularly in hot water.

4 - Chemical Products

Why are we concerned?

Some of the products that we buy and use in our homes can also affect our health, if not used according to directions. These products include household cleaners, personal-care products, and pesticides approved for indoor use. Protect everyone in your home, including those with sensitivities, young children and pregnant women by following these tips.

Recognize these warning symbols

  • Poison - the contents of containers with this symbol are poisonous if swallowed, touched or inhaled.

  • Corrosive - the contents of containers with this symbol will burn skin or eyes and can also burn the stomach if swallowed.

  • Flammable - the contents of containers with this symbol catch fire easily if near heat, flames or sparks.

  • Explosive - containers with this symbol can explode if heated or punctured.

Each warning symbol also has one of these words under it.

  • CAUTION - means a temporary injury may occur from improper use of the product. Death may occur after extreme exposure.

  • DANGER - means that the product may cause temporary or permanent injury, or death.

  • EXTREME DANGER - means that being exposed to even a very low quantity of the product may cause death, or temporary or permanent injury. Be very, very careful.

Tips - What can you do?

  • Follow directions on the labels that tell you how to use, store and dispose of products safely.

  • Always wear protective clothing (e.g. gloves, masks, eye protection) when using and handling chemical products.

  • Open your windows, weather permitting, when using any product with ingredients that may pose a risk. If possible, use the product outside or in a ventilated area.

  • Teach children the symbols for DANGER!

  • Make sure chemical products are stored properly:

    • Keep all chemical products out of sight, away from food and out of reach of children (such as in a high cupboard or closet and not under the kitchen sink).

    • Store household chemicals preferably in locked cabinets and in their original containers. Do not remove or cover up the symbols and labels on containers.

    • Store fuels and oils in proper containers. Make sure that these products and any machinery containing these products are properly stored outside of your home.

    • Make sure that insect repellents are stored away from children's reach.

    • Read the label before each use. If there is anything in the label instructions that you do not understand, ask for help.

    • Never mix chemicals together. Some mixtures can produce harmful gases (such as bleach and toilet bowl cleaner).

    • Make sure that child-resistant containers are being used.

      • Child-resistant does not mean child-proof. Close the cap on the container all the way even if you set it down for just a moment and make sure that these child-resistant caps are working properly.

  • If there are people in the home who suffer from allergies, avoid the use of deodorizers, air fresheners or scented household cleaners. The chemicals in these contain irritants, which can cause allergic reactions and aggravate asthma and other breathing problems in people who are susceptible. You can use a solution of white vinegar and water as an alternative to clean your home.

5- Carbon monoxide

Carbon monoxide (CO) is a harmful gas that has no colour, smell or taste. It is impossible to detect without a carbon monoxide alarm. It can come from unvented kerosene and gas space heaters; gas water heaters, charcoal burners, gas stoves; exhaust from generators and other gasoline powered equipment like cars or snowmobiles; and tobacco smoke.

Why are we concerned?

Even at low levels of exposure, CO can cause breathing problems and headaches. The health effects at higher levels can be much more serious and can even cause death.

Tips - What can you do?


    Install at least one carbon monoxide alarm in your home certified by a certification body that is accredited by the Standards Council of Canada.  The alarm will have a certification mark on it, such as CSA, Ul, Intertek ETL, etc.. It is important to place the alarm close to the floor as CO is heavier then air. If you install the alarm too high, it will not be able to detect the proper levels of CO in your home. Follow instructions for where the alarm should be placed .This type of alarm will alert you early if there is too much CO in your home.
  • Maintain appliances such as furnaces, gas stoves and water heaters so they work properly. Have them inspected by a professional at least once a year.
  • Never use barbecues or outdoor/camping stoves indoors. Do not use a kerosene or oil lamp, or a space heater, in an enclosed space unless the label clearly says they are made specifically for indoor use.
  • Do not start cars, trucks, snowmobiles or other vehicles or let them idle near open doors or windows.
  • Never run gas powered machinery in unventilated areas.
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