Mold is derived from fungal microorganisms. This group of organisms similarly includes fungi and yeasts. The molds grow under certain favorable conditions including the presence of moisture and a nutrient which must be of organic type. Moisture can result from several problems, including water entering a building or inadequate ventilation. The nutritive material may consist of several substances including: plant material, wallpaper, adhesives, cardboard tiles for suspended ceilings, or any material that easily absorbs water.
Of a general nature, molds can be identified by the presence of discoloration spots (black, green, gray and white), musty or earthy odors. In addition, they can also be found in non-visible places, ex. inside walls or ventilation ducts. Depending on the type of mold present, the exposure time and the condition of the occupants, mold can lead to health problems (eg.: allergies and respiratory diseases) in addition to structural problems within the building. According to the Canada Mortgage and Housing Corporation (CMHC), many groups of people are at risk for developing health problems. These groups include pregnant women, young children and the elderly, as well as those who already have health problems such as respiratory problems or a weakened immune system. Thus, these people are at higher risk when they are exposed to mold.
Since molds require a lot of moisture to grow, it is important to control the relative humidity inside a building. In this regard, CMHC recommends that the relative humidity of a room be kept below 50%. In the event of a source of moisture from outside (eg.: water seepage or condensation), the exterior walls of the building must be repaired to maintain adequate ventilation.
It should be noted that, according to CMHC, mold on small surfaces (eg.: window sills) does not pose a serious problem. In the event that there are large impacted areas (eg.: plasterboard), it is recommended that Environment PH be contacted for the services related to mold sampling and air testing of your building.