Healthy places Air Quality Mould


What is mould?

Moulds are fungi, a group of organisms that occur naturally in the environment. Moulds release spores into the air that can be carried into our homes and buildings. If the growth conditions are right, these spores will act like seeds and form new mould.

What does mould need to grow?

Mould needs three things to grow: 

  1. Temperature
  2. A growth medium such as drywall, wood, paper products, damp products, etc.
  3. Moisture

Mould growth is often caused by a moisture problem as most homes and buildings already provide the right temperature and nutrients. 

What are some common sources of moisture?

Common sources of moisture in buildings include:

  • Flooding, leaks or damp basements
  • Steam from the bathroom, kitchen or laundry
  • Condensation from poor or improper insulation or ventilation
  • Humidifiers
  • Poor or improper ventilation of combustion appliances

What are the health effects of mould?

The potential health effects that may associated with mould exposure include: 

  • Eye, nose and throat irritation
  • Runny nose and congestion
  • Increased asthma attacks
  • Allergic reactions

If you are experiencing these symptoms, please consult a physician.

Who is most at risk for health problems from mould exposure?

Some individuals may be at a higher risk of experiencing health problems from mould exposure, including:

  • Older adults 
  • Pregnant women
  • Infants and young children
  • Individuals with allergies, chronic respiratory illness and/or chemical insensitivities
  • Individuals with weakened immune systems

How can I prevent mould from growing in my home?

There are a number of steps you can take to prevent mould growth in your home: 

  • Control humidity. Avoid high humidity in your home, especially for a prolonged period of time. Use a dehumidifier if necessary.
  • Ventilate your home. Use exhaust fans when bathing, showering, cooking and doing laundry. Open windows when necessary.
  • Control moisture. Repair any leaks, and thoroughly clean and dry water-damaged materials. Remove any materials that cannot be properly cleaned and dried.

Should I test for mould?

Because mould is a natural part of the environment and there are always mould spores in the air, it is not recommended that you test for mould in your home. 

What should I do if I have mould?

The methods for removing mould vary and are dependent on the size and number of mould patches present in the home. 

Small areas or areas with fewer than 3 patches, with each patch less than 99 cm in size may be cleaned using soap and water. Always use unscented detergent (not bleach) and be sure to dry the area thoroughly.

The following personal protective equipment should always be used when removing mould:

  • Disposable dust mask (3M 8210 or equivalent)
  • Eye protection
  • Household rubber gloves

Large areas or areas with more than 3 patches, with each patch greater than 99 cm in size should be cleaned by professionals.

In all cases, it is important to find the source of moisture and correct it, or else mould will continue to grow.

What should I do if I am concerned about mould in my rental unit?

For small areas of mould:

  • Clean the area with soap and water.

For large areas of mould or recurring mould: 

  • Increase the ventilation in the home by opening windows or using fans.
  • Notify your landlord or property manager in writing.
  • Give your landlord or property manager a reasonable amount of time to remediate the problem.

If you need further assistance, please contact your local by-law office or call Oxford County Public Health and ask to speak to a Public Health Inspector: 519-539-9800 or 1-800-755-0394.

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