Excessive indoor moisture can lead to the growth of mold inside buildings. Leaks from plumbing, roofs, or window frames cause the biggest problems, and lack of ventilation in kitchens and bathrooms cause mold to grow around window frames, on or around bathroom tiles, and on cold walls. Few people suffer serious health effects from exposure to indoor molds, though some people have allergic or irritant reactions. The key to successful mold prevention and control is to reduce indoor moisture: it is impossible to remove all mold and mold spores indoors, but mold will not grow if moisture is not present.

Disinfectants such as chorine bleach used to be routinely recommended for cleaning up mold or mildew. However, thinking on this is changing, and many experts no longer recommend disinfecting for this purpose. The most important thing is to find and correct the source of the moisture and to dry wet building materials and furnishings within 24-48 hours. Once surfaces are kept dry, the mold cannot grow.

On this page you will find links to sources of information on the hazards associated with mold problems in homes, schools, and other buildings, how mold can be tested, guidelines for reducing indoor moisture that contributes to mold problems, and much more.

General information on mold prevention and control:

• A Brief Guide to Mold, Moisture, and Your Home. EPA.
• The Facts About Mold (includes glossary of mold terms). American Industrial Hygiene Association.
• Got Mold? Frequently Asked Questions. Office of Environmental Health and Safety, Division of Environmental Health, Washington State Department of Health.
• A Brief Guide to Mold in the Workplace. Occupational Safety and Health Administration.

Mold Testing:

• Mold Testing. Nathan Yost, MD,  Joseph Lstiburek, Ph.D., P.Eng., and Terry Brennan, M.S., Building Science Corporation, January 2002. (third article from top)

Guidelines for reducing indoor moisture:

• Moisture and Mold. Canada Mortgage and Housing Corporation.
• Relative Humidity. Joseph Lstiburek, Ph.D., P.Eng., Building Science Corporation, April 2002. (Scroll down to the section on Common Household Problems)

Guidelines for remediating mold and water damage in buildings:

• Mold Remediation in Schools and Commercial Buildings. EPA, March 2001.
• Mold Remediation in Occupied Homes. Nathan Yost, MD, Joseph Lstiburek, Ph.D, P.Eng., and Terry Brennan, M.S., Building Science Corporation, January 2002. (Fourth article from top)
• Managing Water Infiltration into Buildings. Environmental Health and Safety Division, University of Minnesota.
• Fact Sheet: Flood Cleanup -- Avoiding Indoor Air Quality Problems. EPA, October 2003.

Health effects of mold:

• Molds in Indoor Workplaces (page 3). Hazard Evaluation System and Information Service (HESIS), California Department of Health and California Department of Industrial Relations, March 2001. (1.4mb PDF File) 
• Position Statement on Adverse Human Health Associated with Molds in the Indoor Environment. American College of Occupational and Environmental Medicine.
• Guidance for Clinicians on the Recognition and Management of Health Effects related to Mold Exposure and Moisture Indoors. Center for Indoor Environments and Health, University of Connecticut Health Center, September 2004.
  

Information on specific mold species, including toxic molds:

• Questions and answers on Stachybotrys chartarum and other molds. Centers for Disease Control and Prevention.
• Material Safety Data Sheets - Infectious Substances: health and safety information on infectious microorganisms, including Aspergillus and other molds and airborne biologicals. Office of Biosafety, Health Canada. (Note: these Material Safety Data Sheets are profiles of infectious microorganisms and are different from MSDSs that provide information on hazards posed by commercial products.)