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Mould Exposure

Mould can grow indoors all year and outdoors from spring to fall. Mould can be found almost anywhere there is moisture.

Mould grows indoors in damp places such as:

  • Basements
  • Bathrooms
  • Around windows where moisture collects
  • Air conditioners
  • Humidifiers

If you have too much moisture in your home, it is important to take steps to reduce it.

Outdoor mould levels are higher during damp periods in the spring, summer and fall, and in damp locations such as in the forest.

How to reduce exposure to mould

  • Keep the indoor humidity level less than 50 per cent—humidity can be measured by a hygrometer (an instrument that measures humidity) available at hardware stores
  • If your basement is damp, use a dehumidifier
  • Stay indoors when mould levels are high
  • Avoid or reduce activities such as cutting grass, raking leaves, camping and working with compost
  • Use an air conditioner to filter out mould spores and to reduce dampness indoors. Replace the filter regularly.
  • Reduce clutter in your home, especially in the basement. Allowing air to move freely will reduce the chance that mould will grow.


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