Dampness is one of the most common causes of poor indoor air. Moulds, which are microscopic fungi, are some of the most widespread living organisms. They reproduce by releasing spores into the air, and use warmth and high humidity to grow. Watch out for mould in the basement, bathroom, kitchen and laundry room – rooms that are most likely to create and hold in dampness.

How does mould affect health?

Mould can cause all kinds of illnesses, like the flu or the common cold, and can also set off allergies or asthma. There are also many more serious illnesses that you can get through the air, and you should know how to protect yourself.

What can you do?

• Check air conditioners, humidifiers, dehumidifiers and air filters, where moulds can collect.
• Keep your home clean and dust-free.
• Always make sure there is plenty of ventilation in your home. This will prevent moisture from building up on walls and windows.
• Turn on exhaust fans, especially when bathing, showering, cooking and doing laundry.
• Use a hygrometer (a tool that measures humidity) to see if you need a de-humidifier. (The relative humidity in your home should be below 50% in the summer and 30% in the winter.)
• Fix leaky roofs and walls.
• If you find a mouldy surface, clean it with a detergent.
• Limit the number of fish tanks and indoor plants in your home; these can raise the humidity level.

BC Lung Association: Clean Air Videos

Canada Mortgage and Housing Corporation: Fighting Mold – The Homeowner’s Guide

Canadian Centre for Occupational Health and Safety: Moulds and Fungi

Canadian Construction Association: Mould Guidelines for the Canadian Construction Industry

Health Canada: Dampness, Mould and Indoor Air

Ministry of Labour: Mould in Workplace Buildings

Toronto Public Health: Mould Fact Sheet