There is a wide variability in how people are affected by airborne mold spore exposure. Currently, there is no established airborne concentration that is known to adversely affect any individual’s health. People who may be affected more severely and quickly than others include:
Infants and children
Individuals with respiratory conditions or allergies and asthma
Persons with weakened immune systems
Those with special health concerns should consult their doctor if they are concerned about mold exposure. Symptoms that may seem to occur from mold exposure may be due to other causes, such as bacterial or viral infections or other allergies.
What to do if you see or smell mold in your home
The most important step is to identify the source(s) of moisture, which result in mold growth, and make repairs to stop them. If you only clean up the mold and do not fix the moisture problem, most likely the mold growth will recur. If the source of the moisture is related to a building failure or fault, such as a burst pipe or leaking roof, a professional contractor should be consulted. In instances where the moisture source does not appear to be related to leaks, floods, structural faults or rising damp, it is most likely due to condensation. If you do not see mold growth but smell a musty odor, mold may be growing underneath or behind water‐damaged materials, such as walls, carpeting, or wallpaper.
Once the source of the moisture has been identified and fixed, you need to decide if removing the mold from the affected areas is something that can be done without professional assistance. If the mold growth was caused by sewage back‐up or other contaminated water, potential pathogens may be present and the work should be performed by a professional contractor that has experience in cleaning buildings damaged by contaminated water.
If the mold growth is due to condensation or small‐scale leak and is limited to a small area (fewer than ten square feet), you can probably do the work yourself following guidelines such as those that have been prepared by the U.S. Environmental Protection Agency (EPA), Canada Mortgage and Housing Corporation and AIHA. On hard surfaces, such as countertops and furniture, use detergent and water to wash mold off and then dry completely. The use of biocides or chemical disinfectants is not recommended as these may be hazardous to occupants. Moldy porous or absorbent materials, such as ceiling tiles, wallboard and carpeting should be removed and replaced. People cleaning mold should wear rubber gloves, goggles and an approved respirator to protect against breathing airborne spores. An N95 respirator would be appropriate for most cleanup projects, provided that you are medically capable of wearing a respirator. If you have health concerns, you should consult your doctor before doing any mold cleanup.
Over the past decade or so, the industry has given rise to many individuals and companies who tout themselves as experts and certified in various aspects of mold investigation and remediation, but who may have little or no practical experience. If you choose to hire a consultants to help identify your problem, or a contractors to perform the cleanup in your home, make sure that they have specific work experience in dealing with and cleaning up mold, and check their references.
Who to call to deal with extensive mold growth in a building
A professional experienced in mold evaluation and remediation, such as an industrial hygienist, may need to be hired to address extensive mold growth in a building. It is important to correct large mold problems as soon as possible by first fixing the source of the moisture problem and removing contaminated materials, then cleaning the surfaces, and finally drying the area completely. If you use outside contractors or professionals, make sure they have experience cleaning up mold. Check their references, and have them follow the recommendations and guidelines given in the information resources at the end of this fact sheet.