By Alison Beer, OSSA Consultant, Ottawa, and Elizabeth Hillier, OSSA Consultant, GTA
Moulds are tiny organisms that produce thousands of spores as part of their reproductive cycle. They can be any colour – red, blue, brown, green, white or black and often look slimy or wooly.
Moulds can be found almost anywhere, especially in dark, moist environments. There are over 100,000 known species with at least 1,000 species commonly found in North America. Indoor moulds usually originate from outside sources like decaying matter, soil and plants. They can grow on various building materials like plastic, metal, insulation, wallpaper, particleboard, ceiling tiles, drywall, plywood, carpet and under padding and the interior surfaces of ventilation system equipment, when the environment is right.
Moulds can become inactive for many years when moisture is not present but will start to grow again once moisture returns. The spores are easily released to the air when the mould is disturbed and will form new colonies when they encounter moisture.
The awareness of toxic moulds in buildings and the possible health effects has increased with the highly publicized removal of the substance from school portables and government buildings.
Exposure to moulds can cause adverse health effects such as a running nose, watery eyes and breathing difficulties. Toxic moulds like stachybotrys chartarum can cause nosebleeds, severe coughing and immune system impairment. Persons allergic to moulds can experience asthmatic attacks when exposed to the mould spores.
An employer must take every precaution reasonable in the circumstances to protect the worker. Although mould is not specifically mentioned under the Occupational Health and Safety Act, work practices must be provided to recognize, assess and control this hazard.
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For more information about moulds in the workplace and its removal you can go to the following sites:
Mould Remediation in Schools and Commercial Buildings
United States Environmental Protection Agency. Office of Air and Radiation, Indoor Environments Division. March 2001
Fungal Contamination of Public Buildings
A Guide to Recognition and Management, Health Canada. June 1995
Guidelines on Assessment and Remediation of Indoor Environments
New York City Department of Health. Bureau of Environmental & Occupational Disease Epidemiology. January 2002
Guide for the Prevention of Microbial Growth in Ventilation Systems
IRSST (Institut derecherche en sante et en securite du travail du Quebec October 1994
Microbial Growth Task Force
American Industrial Hygiene Association
May 2001
Guidelines for the Investigation, Assessment and Remediation of Mould in the Workplace
Manitoba LabourMarch 2000
Mould Remediation Basic Procedures
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WHMIS training has to be reviewed annually by an employer and in consultation with a health and safety representative or JHSC.