Molds are fungi that are found everywhere – both indoors and outdoors all year round. The terms fungi and mold are often used interchangeably, but mold is actually a type of fungi. Concern about indoor exposure to mold has increased along with public awareness that exposure to mold can cause a variety of adverse health effects. There are many thousands of species of mold and most if not all of the mold found indoors comes from outdoor sources. It seems likely to grow and become a problem only when there is water damage, high humidity, or dampness.

Molds produce and release millions of spores small enough to be air-, water-, or insect-borne. They can also produce toxic agents known as mycotoxins. Spores and mycotoxins can have negative effects on human health. Tor those people who are affected by mold exposures there can be a wide variation in how they react. People at greatest risk of health effects are individuals with allergies, asthma, sinusitis, or other respiratory conditions, as well as infants and children, elderly people, and pregnant women. In addition, individuals with a weakened immune system are at risk.

Mold is addressed in specific standards for the general industry, shipyard employment, and the construction industry.

Standards

This section highlights OSHA standards, Federal Registers (rules, proposed rules, and notices), standard interpretations (official letters of interpretation of the standards), and national consensus standards related to mold.

OSHA

Note: Twenty-five states, Puerto Rico and the Virgin Islands have OSHA-approved State Plans and have adopted their own standards and enforcement policies. For the most part, these States adopt standards that are identical to Federal OSHA. However, some States have adopted different standards applicable to this topic or may have different enforcement policies.

General Industry (29 CFR 1910)

• 1910.141, Sanitation

Shipyard Employment (29 CFR 1915)

Construction Industry (29 CFR 1926)

• 1926.51, Sanitation

Federal Registers

• Assigned Protection Factors. Final Rules 71:50121-50192, (2006, August 24). Revises the existing Respiratory Protection Standard to add definitions and requirements for Assigned Protection Factors (APFs) and Maximum Use Concentrations (MUCs). The revisions also supersede the respirator selection provisions of existing substance-specific standards with these new APFs (except for the respirator selection provisions of the 1,3-Butadiene Standard).
  
  
• Indoor Air Quality. Notice 66:64946, (2001, December 17). OSHA withdrew its Indoor Air Quality proposal and terminated the rulemaking proceeding.
  
  
• Respiratory Protection. Final Rules 63:1152-1300, (1998, January 8). Justifies the use of respirators to prevent the inhalation of harmful airborne contaminants that are alive or were released from a living organism. Respirators protect against bacterial infections resulting from inhalation of bacteria and their products that cause a range of diseases.
  
  
• Indoor Air Quality. Proposed Rules 59:15968-16039, (1994, April 5). OSHA proposed to adopt standards that addressed indoor air quality in indoor work environments.
  
  
• Search all available Federal Registers.

Standard Interpretations

• Enforcement Policy for Respiratory Hazards Not Covered by OSHA Permissible Exposure Limits. (2003, January 24).
  
  
• Record retention requirements for indoor air quality documents and reports. (2002, August 1).
  
  
• Search all available standard interpretations.

National Consensus and Industry Standards

Note: These are NOT OSHA regulations. However, they do provide guidance from their originating organizations related to worker protection.

American National Standards Institute (ANSI)/American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE)

• 62.1-2007, Ventilation for Acceptable Indoor Air Quality. Sets minimum ventilation rates and other requirements for commercial and institutional buildings.

Institute of Inspection, Cleaning and Restoration Certification (IICRC)

• S500, Standard and Reference Guide for Professional Water Damage Restoration. Provides a specific set of practical standards for water damage restoration. It does not attempt to teach comprehensive water damage restoration procedures; rather it provides the foundation for basic principles of proper restoration practices.
  
  
• S520, Standard and Reference Guide for Professional Mold Remediation. Establishes mold contamination definitions, descriptions and conditions (1, 2, 3), and general guidance, which, when properly applied, can assist remediators and others in determining criteria that trigger remediation activities or confirm remediation success.

Hazard Recognition

Mold growth is encouraged by warm and humid conditions. It is likely to grow and become a problem where there is water damage, high humidity, or dampness. It is estimated that about 50 to l00 common indoor mold types have the potential for creating health problems. Exposure to molds can cause symptoms such as nasal stuffiness, eye irritation, or wheezing. Some people, such as those with serious allergies to molds, may have more severe reactions. The following references aid in recognizing workplace hazards and health effects associated with mold hazards.

• Preventing Mold-Related Problems in the Indoor Workplace [207 KB PDF^*, 36 pages]. OSHA, (2006). Provides building owners, managers and occupants with basic information about mold, mold sources, and building-related illnesses.
  
  
• Mold. Centers for Disease Control and Prevention (CDC), National Center for Environmental Health (NCEH).
  • Molds in the Environment. (2005, March). Provides basic facts about molds.
  • Facts about Stachybotrys chartarum and Other Molds. Provides answers related to health concerns with Stachybotrys chartarum and other molds.
    
    
• An Introduction to Indoor Air Pollution - Biological Pollutants. Environmental Protection Agency (EPA), (2007, May 22). Identifies biological contaminants including bacteria, molds, mildew, viruses, animal dander and cat saliva, house dust, mites, cockroaches, and pollen. It describes their health effects, presents measures for reducing exposure, and lists additional resources on the topic.
  
  
• Mold Resources. Environmental Protection Agency (EPA). Provides general information and links about molds and mold-related issues such as moisture control, flooding, and asthma.
  • A Brief Guide to Mold, Moisture and Your Home. EPA 402-K-02-003, (2002, July). Provides information and guidance for homeowners and renters on how to clean up residential mold problems and how to prevent mold growth.
  • Mold Remediation in Schools and Commercial Buildings. EPA 402-K-01-001, (2001, March). Presents guidelines for the remediation/cleanup of mold and moisture problems in schools and commercial buildings; these guidelines include measures designed to protect the health of building occupants and remediators. It has been designed primarily for building managers, custodians, and others who are responsible for commercial building and school maintenance.
    
    
• Facts About Mold [85 KB PDF, 8 pages]. American Industrial Hygiene Association (AIHA), (2011, December 16). A consensus statement by a group of experts about important aspects of the "state of the science". Presents a variety of mold facts, including health effects, cleanup, and recommended methods for prevention of mold growth and mold exposure.
  
  
• Fungi in Buildings. University of Minnesota, Department of Environmental Health and Safety, (2007, May 11). Provides links to "Indoor Fungal Resources" that contain information on investigation of indoor fungi, water infiltration control, a fungal abatement protocol, and a glossary of fungi-related terms.

Health Effects

• Fact Sheet on Natural Disaster Recovery: Fungi. OSHA. Discusses the hazards and health risks to clean-up workers. Provides information on what should be done if symptoms occur and tips to remember.
  
  
• Histoplasmosis: Protecting Workers at Risk. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 2005-109, (2004, December). Introduces the fungal disease histoplasmosis and includes information about exposure, diagnosis, and prevention.
  
  
• State of Science on Molds and Human Health [72 KB PDF, 12 pages]. Centers for Disease Control and Prevention (CDC), (2002, July). Identifies a variety of illnesses that people exposed to molds may experience. Fungi account for 9% of nosocomial infections, that is, infections originating or taking place in a hospital. Ingestion of foods contaminated with certain toxins produced by molds is associated with development of human cancer. Many respiratory illnesses among workers may be attributed to mold exposures. Linkages between indoor airborne exposures to molds and other health effects, such as bleeding from the lung, or memory loss, have not yet been scientifically substantiated.
  
  
• Update: Pulmonary Hemorrhage/Hemosiderosis Among Infants --- Cleveland, Ohio, 1993-1996. Centers for Disease Control and Prevention (CDC), Morbidity and Mortality Weekly Report (MMWR) 49(09);180-4, (2000, March 10). Reports on its review and reanalysis of the 1993-1996 Cleveland, Ohio infant lung bleeding cases that brought Stachybotrys chartarum mold to national attention. CDC concludes that exposure to this or other molds was not proven to be associated with lung bleeding in these cases.
  
  
• Molds, Toxic Molds and Indoor Air Quality [91 KB PDF, 19 pages]. California Research Bureau, (2001, March). Provides background information on molds, their potential health effects, and how they relate to indoor air quality.
  
  
• Molds in Indoor Workplaces [143 KB PDF, 4 pages]. Hazard Evaluation System and Information Service (HESIS), California Department of Health and California Department of Industrial Relations, (2005, November). Describes allergic reactions, fungal infections and other health effects that molds cause. Most workers will have no reaction when exposed to mold, however, some workers have underlying health conditions that make them more sensitive to mold exposure.
  
  
• Health Effects of Toxin-Producing Molds in California. California Department of Health Services, California Morbidity (Monthly Report), (1998, April). Describes what is known about health effects of toxin-producing molds in the indoor environment, especially Stachybotrys chartarum. This article discusses mechanism of action, route of exposure and summarizes cases from the medical literature.
  
  
• McNeel, S.V. and R.A. Kreutzer. "Fungi & Indoor Air Quality." Health & Environment Digest 10.2(1996, May-June): 9-12. California Department of Health Services, Environmental Health Investigations Branch. Discusses mold species commonly associated with indoor air. It also provides information on mycotoxins, including their origins and effects on humans. 
  
  
• Barrett, J.R. "Mycotoxins: Of Molds and Maladies." Environmental Health Perspectives 108.1(2000, January). Provides an overview of mycotoxins, mold species commonly associated with human disease, health effects, exposure risks, and current research topics.
  
  
• Mold Allergy. Asthma and Allergy Foundation of America. Provides information on mold allergies including prevalence, symptoms, methods of diagnosis, treatment, and prevention measures.
  
  
• Farmer's Lung: Causes and Symptoms of Mold and Dust Induced Respiratory Illness. National Agriculture Safety Database (NASD), (2002, April). Presents information on the respiratory illness caused by inhalation of mold spores known as Farmer's Lung. Includes descriptions of symptoms, diagnosis, treatment, and preventative measures.
  
  
• Ampel, N.M. "Emerging Disease Issues and Fungal Pathogens Associated with HIV Infection." Emerging Infectious Diseases 2.2(1996, April-June). Discusses fungal diseases associated with HIV patients.
  
  
• Kirkland, T.N. and J.F. Fierer. "Coccidioidomycosis: A Reemerging Infectious Disease." Emerging Infectious Diseases 2.3(1996, July-September). Provides an overview of coccidioidomycosis, including its epidemiology, clinical aspects, treatment, and prevention.
  
  
• Fungi and Bacteria in Ventilation Systems. Penn State Architectural Engineering & Biology Departments, Aerobiological Engineering Series, (2001). Lists fungal allergens and pathogens of concern in indoor air quality (IAQ).

Detection Methods

The following references provide information about methods used to detect potentially dangerous mold in the workplace.

• EPA Scientists Develop Technology for Detection of Dangerous Molds. Environmental Protection Agency (EPA), (2001, May 8). Explains the development of a faster and more accurate method to detect potentially dangerous molds, including Stachybotrys, commonly known as "black mold," and more than 50 other possibly problematic molds.

Control and Clean-up

Emphasis should be placed on preventing contamination through proper building maintenance and prompt repair of water damaged areas. The following resources contain information to help prevent and control workplace hazards.

• A Brief Guide to Mold in the Workplace. OSHA Safety and Health Information Bulletin (SHIB) 03-10-10, (2003, October 14). Provides recommendations for the prevention of mold growth and describes measures designed to protect the health of building occupants and workers involved in mold cleanup and prevention.
  
  
• Metalworking Fluids: Safety and Health Best Practices Manual. OSHA. Provides information in Section H of this manual about the control of bacterial and fungal growth in metalworking fluids.
  
  
• Guidelines on Assessment and Remediation of Fungi in Indoor Environments. New York City Department of Health and Mental Hygiene, Bureau of Environmental and Occupational Disease Epidemiology, (2007). Addresses mold contamination of building components that are chronically moist or water damaged such as, walls, ventilation systems, and support beams. It provides information about assessment, inspection, sampling, and controls.
  
  
• Mold. National Institute of Environmental Health Sciences, (2005, April 25). Defines and describes mold spores and strategies for asthma and allergy prevention.
  
  
• Asthma Triggers: Gain Control - Molds. Environmental Protection Agency (EPA). Describes actions one can take to reduce the presence of molds in indoor environments.
  
  
• Hurricane Preparedness and Response. OSHA. Includes information such as news releases, public service announcements, fact sheets, frequently asked questions, and more.

Clean-up Procedures

• Flood Cleanup. Environmental Protection Agency (EPA), (2007, April 25). Provides basic information on how to clean up after a flood and how to prevent indoor air problems.
  
  
• Mold Remediation in Schools and Commercial Buildings. Environmental Protection Agency (EPA), Office of Air and Radiation, Publication No. 402-K-01-001, (2001, March). Also available as 5 MB PDF, 54 pages. Contains instructions for cleanup and remediation of molds and moisture-related problems in schools and commercial buildings.
  
  
• A Brief Guide to Mold, Moisture, and Your Home. Environmental Protection Agency (EPA), Office of Air and Radiation, Publication No. 402-K-02-003, (2002). Also available as 1 MB PDF, 20 pages. Covers basic mold facts, cleanup concerns and recommendations, and moisture-control tips.

Additional Information

Training

• Introduction to Mold and Mold Remediation for Environmental and Public Health Professionals. Environmental Protection Agency (EPA) Mold Web Course. Also available as a 5 MB PDF, 202 pages. Gives specific recommendations for personal protective equipment (PPE) when cleaning mold.

Other Resources

• American Biological Safety Association (ABSA). OSHA Alliance Page.
  
  
• Division of Foodborne, Waterborne, and Environmental Diseases (DFWED). Centers for Disease Control and Prevention (CDC), National Center for Infectious Diseases. Provides links for disease facts, current news, and publications.
  
  
• Mold. Centers for Disease Control and Prevention (CDC). Lists links to general information about mold, identifying mold problems, remediation and cleanup.
  
  
• Indoor Air Quality. Environmental Protection Agency (EPA). Provides a gateway into EPA's indoor air pollution information.
  
  
• Molds and Moisture. Environmental Protection Agency (EPA). Provides a gateway into EPA's Mold information, including an introduction, frequently asked questions, and publications.

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