Frequently Asked Questions


What is mold?

Molds are form of fungus that can be found both indoors and outdoors. There are thousands of species of mold with estimates ranging from tens of thousands to perhaps three hundred thousand or more. Mold spreads and reproduces by making spores. Spores can survive conditions that are too sunny, hot, cold, dry or wet for mold to grow. When spores are released they can be carried by air or water to new locations.

What causes mold in your home?

Excess moisture caused by leaks or flooding in your home. Damp environments like your kitchen, laundry room and bathrooms creates the perfect breeding ground for mold or mildew. These areas of the home are called “amplification sites.” To control and reduce the risk for mold growth in these areas, you must properly maintain your plumbing system and monitor appliances that use large quantities of water, like dish washers and washing machines. Small amounts of indoor mold are unavoidable and usually harmless. In damp environments, however, mold spores can more easily reproduce.

How does mold spread in your home?

For molds to grow and reproduce, they only need an organic food source, such as cellulose, which is found in building materials such as wood and drywall. The amount of moisture in these materials influences how an organism can support growth. Moisture sources would include condensation in humid rooms, on windows, unheated closets, dampness under carpets and on shower curtains, and periodic wet sections in ductwork of air conditioned ventilation. Temperature is also a factor that affects mold growth. Molds typically require temperatures between 5°C and 38°C to grow.

Can the presence of mold in your home be easily identified?

If there are dark spots on your ceiling, floors or walls, this is a sure sign of mold growth. Musty odours and mildew are often signs that mold may be growing in your home. However, not all mold is visible at the surface. Past studies have indicated that up to 90% of mold growth is not visible. Certain guidelines state that invasive inspection is necessary to make a complete assessment of the extent of mold contamination in the home.

What are the health risks if there is mold in your home?

Some molds are more hazardous than other molds, and different people have different responses to mold exposure. In particular, those with allergies, existing respiratory conditions or suppressed immune systems are especially susceptible to health problems from mold exposure. Additionally, infants and children, pregnant women, and the elderly can be sensitive to the effects of mold exposure. Some people that are exposed to mold experience allergic reactions, with symptoms similar to hay fever and the common cold but that last for longer periods, while others can experience aggravation to asthma. Researchers have identified that some fungi in indoor environments can induce allergic and irritant response, infectious disease, respiratory problems, hypersensitivity reactions, and organ toxicity. In addition, some molds produce chemicals called mycotoxins, which can cause flu-like symptoms.

Carbon Monoxide

What is carbon monoxide?

Carbon monoxide (CO) is a colourless and odourless gas which is particularly dangerous as you can’t see it, taste it or smell it. It can affect you and your family before you even know it is there.

How does carbon monoxide get into your home?

Carbon monoxide (CO) is a common by-product of the combustion (burning) of fossil fuels. Most fuel-burning equipment, such as the furnace in your home, if installed properly and maintained regularly, produces little CO and are vented to the outside. However, if anything disrupts the venting process (something clogging the chimney or vent pipe) and results in a shortage of oxygen to the burner, the presence of carbon monoxide can quickly rise to dangerous levels. Additionally, the burning of wood, coal, kerosene and charcoal produce CO, as well as gasoline engines. Starting your gas lawnmower or idling your car in the garage can be dangerous not only in the immediate area, but CO can enter your home through connecting walls and doorways.

What are the health risks if there is carbon monoxide in your home?

Carbon monoxide can cause serious health problems even at low levels of exposure. Carbon monoxide will rapidly accumulate in the blood and deplete the ability of the blood to carry oxygen. With mild exposure, you might experience flu-like symptoms such as a headache, runny nose and sore eyes. As exposure increases you will feel drowsy, dizzy, disoriented and could start vomiting. At this stage, it may be difficult to make the decision to leave your home. Extreme exposure will lead to unconsciousness, brain damage and then death.

What should you do to prevent carbon monoxide in your home?

The best way to eliminate the possibility of carbon monoxide poisoning is to ensure it never enters your home. As a preemptive measure, you should have a qualified technician inspect your fuel-burning appliances, chimney and vents, fireplaces and examine the utilities room in your home to ensure there is adequate air for proper combustion. It is also important that every home have a CO detector to give you warning when high level of CO is reached in a short time.


What is radon?

Radon is a gas that is formed by the breakdown of uranium in the soil. Uranium is a natural radioactive material found in rock and soil. Although radon is found in outdoor air, it can enter a home through the basement walls or floor. Radon can enter through cracks and other holes in the foundation. Your home can trap radon inside, where the concentrations then build up. Any home may have a radon problem including new and old homes, well-sealed and drafty homes and homes with or without basements. Concrete-block walls are particularly porous to radon.

Why should you be concerned about radon gas in your home?

Since radon is a radioactive gas, when it’s in your home it can pose a danger to your family’s health, and you won’t know it is there as you can’t see, smell or taste it. Radon is the leading cause of lung cancer among non-smokers and is the second leading cause of lung cancer in Canada. All major national and international organizations that have examined the health risks of radon agree that it is a lung carcinogen.

How do you know if there is radon in your home?

The only way to know for sure if there is radon gas in your home is to get a test done by a qualified inspection company, such as AmeriSpec. There are two types of tests; a short-term test which is 48 hours in length and a 90 days test which is highly recommended by Health Canada. With either of these tests, the device must be removed from the home for analysis and a report will be issued to you indicated the level of radon in the home and whether work should be done on your home to reduce the level of radon.

Is there an acceptable amount of radon in your home?

In Canada, radon is measured in units called “becquerels per cubic meter” (Bq/m3 is a measurement of the number of radioactive disintegrations per minute).  Although there are no regulations regarding acceptable levels of radon in indoor air in Canada, Health Canada’s 2007 guideline recommends that remedial measures be taken in a dwelling whenever the average annual radon concentration in the normal occupancy area exceeds 200 becquerels per cubic meter. 

Are there building code guidelines for radon in new home construction?

Health Canada has proposed that for newly constructed homes, the guideline should be 100 Bq/m3 or less. To meet that target, under the National Building Code of Canada some measures may be required to prevent radon from entering the home. These measures would include minimizing potential entry routes into the home in the basement floor of foundation walls, proper choice of heating and ventilation that reduce forces that may draw radon into the home, and including provisions for an active soil depressurization system.


What is Asbestos?

Asbestos is a group of naturally occurring silicate minerals that are fibrous in nature.  Asbestos fibres are soft and flexible yet resistant to heat, electricity and chemical corrosion.  Asbestos is an effective insulator and can be mixed into all kinds of substances including paper, cloth, cement, plastic and other materials to make them stronger.  Before 1990, asbestos was mainly used for insulating buildings and homes against cold weather and noise.  It was also used for fireproofing, and in construction products such as cement and plaster, furnaces and heating systems, floor and ceiling tiles and house siding.

When did they stop using asbestos building products in the home in Canada?

The manufacturing of most materials containing asbestos was banned in Canada in 1979.  However, many non-friable materials continued to be produced and also stockpiles of products were still in existence for years later, therefore asbestos products can be found in building built into the early 1990s.

What are the health risks of exposure to asbestos?

Asbestos fibres are microscopic and therefore cannot be seen, nor can the fibres be smelled or tasted, so it is easy to inhale or swallow asbestos dust without realizing it.  Once asbestos fibres are in the body, they never dissolve and the body has extreme difficulty expelling them.  Over years, trapped asbestos fibres can cause inflammation, scarring and eventually genetic damage to the body’s cells.  It can take between 20 to 50 years for asbestos-related illnesses to materialize, therefore most cases today were caused by asbestos exposures that occurred before modern safety regulations came into effect.  Asbestos fibers most often accumulate in lung tissue and in the membrane lining the lungs. Benign asbestos-related diseases include asbestosis, pleuritis and chronic obstructive pulmonary disease (COPD), which make it difficult for patients to breathe.  Asbestos also causes malignant diseases such as lung cancer and mesothelioma which is a rare cancer of the lining of the chest or abdominal cavity.

How can you be exposed to asbestos in your home?

It is important to note that there are no significant health risks if asbestos materials in your home are tightly bound in products and in good condition, if they are sealed behind walls and floorboards or isolated in an attic and the materials are left undisturbed.  However, if you are renovating or demolishing your home small asbestos fibres can be released into the air.  If you suspect that your home has asbestos products, you should have these materials tested prior to a major renovation.

How do you reduce your risk of exposure to asbestos in your home?

If you are considering a renovation, demolition or adding an addition to your home, you can reduce your risk of exposure by hiring a professional to test for asbestos.  If asbestos is found, hire a qualified asbestos removal specialist to remove these products before beginning work.  You should avoid disturbing asbestos materials yourself as this increased the risk to you and your family’s health.  If you have vermiculite-based insulation in your attic, it may contain asbestos.  To avoid exposure do not disturb the attic insulation and you should not allow children in the attic or use the attic for storage.  All cracks and holes in the ceiling of the rooms below the insulation should be sealed and caulk around light fixtures and the attic hatch.  You may also want to caulk windows, door frames, baseboards and around electrical outlets in case the insulation has fallen through the walls over time.

Airborne Particles Testing

What is airborne particle pollution in my home?

Airborne particles can come from sources such as cigarette smoke, cooking (especially frying), malfunctioning furnaces, wood burning appliances and mold growth.  Other sources of airborne particle pollution include burning candles, home renovations and ongoing activities that cause increase in dust and airborne particulate matter in the home. Particulate matter can also be formed from substances such as carbon (soot), liquid or solid particles in aerosols, fungal spores, pollen or toxins present in bacteria.

Should the presence of airborne particles in your home be of concern?

Airborne particles can be harmful to your health if they are 3 microns or less.  Small airborne particles can easily travel deep into the lungs.  The health risks associated with inhaling airborne particles include respiratory symptoms such as wheezing and coughing.  Children and pregnant mothers are at a higher risk for developing health problems associated with inhaling airborne particles, such as cancer, asthma, cardio-vascular disease, premature delivery, and birth defects.

Airborne Chemicals Testing

What are VOCs?

Volatile Organic Compounds (VOCs) are a large class of organic, carbon-based chemicals and are present in the air in almost every home.  VOCs can be caused from burning fuels, cooking food, common cleaning products, soaps, hair sprays, air fresheners and they can also be released into the air by new building materials, furnishings, carpets, windows, wall and floor coverings and paint.  VOCs are gases emitted at room temperature, so they can circulate freely through the air in your home.

Are there health risks associated with airborne chemicals (VOCs) in your home?

The health symptoms related to risk levels of volatile compounds in your home can range from temporary dizziness, headaches, fatigue and mild irritation to cancer, nerve damage and liver and kidney problems.

What is off gassing?

Off gassing is something that happens continually, although it happens at a faster pace when something is drying (such as paint or glue) or when temperatures increase.  Products like new building materials, furnishings, carpets, windows, wall and floor covering and paint will slowly release their VOCs into the air.  This process can take up to years before it completely stops.

What should you do if you suspect that you have a high level of VOCs in your home?

If you suspect you have been affected by the presence of VOCs in your home, or if you would like to limit the amounts of VOCs in a new renovation project, it is best to consult with a professional to identify and mitigate your exposure.  Professionals are experienced in identifying sources of VOCs and can administer tests to determine if you have an issue in the home.  They will also be able to determine if there is proper ventilation in the home.

Excess Humidity

Why should you be concerned about the humidity levels in your home?

High levels of humidity can cause discomfort for you and your family, but more importantly, it contributes to the growth of mold and other microbial organisms that can adversely affect your health. Excess humidity levels can also lead to long-term damage to your home, including structural damage, if not treated properly. High humidity and mold can also create an old, stale, musty or earthy smell in your home.

What are the common causes of excess humidity in your home?

One of the main causes of excess humidity in your home is poor ventilation.  The level of ventilation in your home including how much fresh air is entering the house from outside and how effectively contaminated air is being exhausted from the house can have a major impact of the quality of air in your home.  Humidity occurs in indoor environments due to building related causes. Porous walls, rising damp, and leaks in the home are determinants for structural dampness due to elevated humidity levels. The construction of the building can also lead to humidity and unwanted moisture in the indoor environment. Wet materials, such as lumber stored unprotected outdoors before construction, can lead to increased humidity indoors for up to the second year of occupancy in a new or newly renovated home.

Are there health affects if your home has excess humidity?

The most immediate effect of high humidity is personal discomfort.  A humid environment is a breeding ground for all sorts of microscopic organisms that can harm your health. Mildew and mold spores thrive in it, and they can be highly toxic once they get into your body. If mold is clearly visible inside your home, you have a problem that needs immediate attention. Even if there are no signs, mold and mildew can still spread throughout the vents, or behind walls. Dust mites also love humidity, and they’re one of the biggest enemies for people who suffer from asthma and allergies. Bed bugs also thrive in humid environments.