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Blog by tomjoneshomes.ca | June 1st, 2006

Health & Structural Risks from Molds in Your Home

What is it?

Molds are fungi that reproduce by releasing tiny spores into the air.  Spores that land on moist objects may begin to grow.  There are thousands of different types of mold, ranging from the non-toxic to toxic mold, and we encounter many of them every day in our homes and outside.

Toxic mold is a type of mold that produces hazardous by-products, called mycotoxins.  The most common toxic mold is a slimy, greenish-black mold that grows on moisture-laden materials that contain cellulose, such as wood, paper, drywall, clothes and other similar products.


What are the Risks?

The toxins found in toxic mold are believed to cause memory loss, severe lung problems in infants and the elderly.  Many types of mold trigger health problems in healthy individuals, especially those with asthma and other respiratory problems.

Even if the mold in a household is most likely not toxic mold, it can still be a problem, because mold growing on organic materials will in time destroy them.  Too much mold of any type not only smells bad, it also degrades air quality.


Where is it?

Mold only grows on moist objects; hence, it thrives in damp, humid conditions.
- Bathrooms with poor ventilation; hence, install an exhaust fan if possible.

- Leaky water pipes.  Repair them immediately, scrub mold off the hard surfaces and dry all items completely.

- Roof leaks.  Repair them right away.

- Flood cleanup should be handled as soon as possible

- Clothes dryers and exhaust fans should always vent to the outside, never under the house or back into a room.


How to Clean It?

When cleaning the mold, make sure the room is well ventilated before you begin.  You can clean visible mold with detergent and water.  Allow to dry, then apply solution of ½ cup bleach per gallon of water to help kill the remaining spores.  However, please be aware that you should never combine bleach and ammonia because the mixture produces a toxic gas.


What to Wear When Cleaning Moldy Areas?

 - Avoid breathing in mold or mold spores.  In order to limit your exposure to airborne mold, make sure you wear an N-95 respirator which is available for purchase in Home Depot.  In order to be effective, the respirator or mask must fit property, so carefully follow the instructions supplied with the respirator.

- Wear gloves.  Long gloves that are made from natural rubber, neoprene, nitrite, polyurethane or PVC is highly recommended.  The length of the glove should extend to the middle of the forearm.

- Wear goggles.  Goggles that do not have ventilation holes are recommended.  Avoid getting mold or mold spores in your eyes.


How Do I Know When the Clean Up is Finished?

Mostly importantly, you must have completely fixed the water or moisture problem before the cleanup can be considered finished.

- Visible mold and moldy odours should not be present. 

- Revisit the sites shortly after cleanup and it should show no signs of water damage or mold growth.

- People should be able to occupy or re-occupy the area without health complaints or physical symptoms.


How to Control and Prevent Mold?

Moisture Control is the KEY to mold control.

- When water leaks or spills occur indoor – ACT QUICKLY.  If wet or damp materials or areas are dried 24-48 hours after a leak or flood happens, then most likely mold will not grow.

- Clean and repair roof gutters regularly.

- Make sure ground slopes away from the building foundation, so that water does not enter or collect around the foundation.

- Keep indoor humidity low.  If possible, keep it below 60% (ideally between 30-50%) relative humidity. 

- When condensation or moisture collects on windows, walls or pipes, it’s a sign of high humidity.  Dry the wet surface and reduce the moisture/water by using air conditioners and/or de-humidifiers.

- Vent appliances that produce moistures, such as clothes dryers, stoves, and dishwasher by using exhaust fans or opening windows.

- Run the bathroom fan or open the window when showering to reduce the humidity.


While toxic mold can definitely be a health hazard, in most instances, its growth can be prevented or stopped if handled properly.