TITLE 8:  Chapter 4, Subchapter 7, Article 9, Section 3362

of the General Industry Safety Orders


General Sanitation Requirements for Mold





This proposal was developed by the Division of Occupational Safety and Health staff (Division) in response to a recommendation made by the Hazard Evaluation System and Information Service (HESIS).  HESIS is a state program sponsored jointly by the Department of Industrial Relations (DIR) and the Department of Health Services (DHS) with the mandate of evaluating occupational health issues and providing information and assistance to both Departments.  The proposal amends the general requirements of the standard to establish unequivocally that mold and mold-infested materials are an unsanitary workplace condition that the employer must clean or remove.  In some instances, these conditions may have been allowed to persist because of a lack of awareness of the potential hazards, and inconsistent interpretation of the standard.  This proposal will enhance the Division's ability to require employers to correct these unsanitary workplace conditions.


The existing California standard has a Federal equivalent, 29 CFR 1910.141(a)(4)(ii).  Neither the California nor the Federal standard currently contains a specific reference to mold or fungus. 


Mold is a generic term for the types of fungus that can grow on structural surfaces or within organic materials generally in the presence of moisture, and includes mildew.  Molds can present two types of problems in the working environment.  First, employees exposed to airborne mold spores or mycotoxins may suffer a variety of adverse health effects of increasing severity ranging from relatively mild allergic reactions similar to hay fever, aggravation of asthma, and in rare cases, hypersensitivity reactions or an invasive infection by some mold species.  The likelihood of lost work time for employees increases with the degree of infestation of the work environment by molds.  Secondly, if mold colonization is not curtailed by cleaning in its early stages, heavy infestations can physically damage the substrates they infest such as carpeting, walls, and other structural components of a building.  This damage would entail not only material replacement costs, but could require remediation procedures which are conducted in a manner similar to lead or asbestos removal and are more costly than standard construction procedures.  It is anticipated that an employer who removes mold as part of the building maintenance procedures will minimize the occurrence of these types of problems.


The presence of molds in California workplaces is generally reported as a subset of indoor air quality complaints by the public agencies that evaluate the problem and current estimates by the agencies that respond to such complaints.  Federal OSHA, in their 1994 Indoor Air Quality (IAQ); Proposed Rule, estimates that 30 percent of non-residential buildings have some type of indoor air quality problem.  The DHS, Environmental Health Investigations Branch, in their report, "Fungi & Indoor Air Quality," cites an approximation that 40 percent of these indoor air problems are due to microorganisms.  This provides an estimate of 12% of workplaces in California to be affected.  The DHS report notes that IAQ assessments had focused primarily on the chemical composition of indoor air until there was more recognition by researchers that molds produce toxins in their spores that produce a variety of health effects.  The Division has responded to complaints from a variety of work environments, but the majority have been in public schools where administrators and staff are very aware of mold related problems.  The California Research Bureau, in a report assessing the effect of molds on indoor air quality for Assemblymember Alan Lowenthal, concludes that,


"All molds under proper conditions and concentrations are capable of adversely affecting human health.  Therefore, it is clear, that reduction and prevention of mold exposure is needed to decrease the risk of damage to human health."


Currently, the use of the regulation to address the problems related to the presence of mold has had mixed results.  Some employers, especially in the case of public schools, already accept that mold is an unsanitary condition and have either taken corrective measures before the inspection was initiated or readily complied with abating the cited condition.  In other cases, the Division has had to enlist the assistance of DHS, and issue special orders to establish that an employer needed to clean surface mold and remove heavily infested materials.  The Division has concluded that this inconsistent ability to apply the standard should be rectified by this proposal.




This proposal is intended to establish that all employers must treat the presence of mold as an unsanitary condition and take corrective actions that will prevent or minimize the occurrence of adverse health effects and the collateral benefit of reducing damage to the structure and contents of the affected work site.


Amended subsection (a) is proposed to require an employer to clean (or have cleaned) mold from interior surfaces and building components or remove materials that are too heavily infested to clean.  The revision is necessary to clearly establish in the regulation that mold is one type of unsanitary condition.  This revision does not require the employer to conduct any sampling of the air or the mold itself to identify the type of mold that is present.  It is currently difficult and costly to conduct meaningful sampling to identify molds or the toxins that they produce.  This type of information would only be useful in the rare instance where an occupant of the site has been infected by a species of mold or is suffering from a hypersensitivity reaction and requires medical treatment.   


The proposal is necessary to clarify the existing intent of the regulation so that employers understand that visible mold or mold-infested building components are a type of unsanitary condition covered by the regulation.




1.      Correspondence to John Howard, Chief of the Division of Occupational Safety and Health, from James Cone, M.D., M.P.H. & Julia Quint, Ph.D., Department of Health Services/Department of Industrial Relations, HESIS, dated October 26, 2000.

2.      Vol. 59, Federal Register, 15968-16039, April 5, 1994.

3.      Sandra V. McNeel, DVM & Richard A. Kreutzer, M.D., California Department of Health Services, Environmental Health Investigations Branch, "Fungi & Indoor Air Quality," May/June 1996.

4.      Pamela J. Davis, California Research Bureau, "Molds, Toxic Molds, and Indoor Air Quality," March 2001.

5.      HESIS, "Molds in Indoor Workplaces," March 2001.


These documents are available for review Monday through Friday from 8:00 a.m. to 4:30 p.m. at the Standards Board Office located at 2520 Venture Oaks Way, Suite 350, Sacramento, California.






No reasonable alternatives were identified by the Board and no reasonable alternatives identified by the Board or otherwise brought to its attention would lessen the impact on small businesses.




This proposal will not mandate the use of specific technologies or equipment.





Costs or Savings to State Agencies


Insignificant to no costs or savings that can not be quantified to state agencies will result as a consequence of the proposed action.

Impact on Housing Costs


The Board has made an initial determination that this proposal will not significantly affect housing costs.


Impact on Businesses


The Board has made an initial determination that this proposal will not result in a significant, statewide adverse economic impact directly affecting businesses, including the ability of California businesses to compete with businesses in other states.


Cost Impact on Private Persons or Businesses


The Board is not aware of any cost impacts that a representative private person or business would necessarily incur in reasonable compliance with the proposed action.


Costs or Savings in Federal Funding to the State


The proposal will not result in costs or savings in federal funding to the state.


Costs or Savings to Local Agencies or School Districts Required to be Reimbursed


No costs to local agencies or school districts are required to be reimbursed.  See explanation under "Determination of Mandate."


Other Nondiscretionary Costs or Savings Imposed on Local Agencies


This proposal does not impose any significant nondiscretionary costs or savings on local agencies.





The Occupational Safety and Health Standards Board has determined that the proposed regulation does not impose a local mandate.  Therefore, reimbursement by the state is not required pursuant to Part 7 (commencing with Section 17500) of Division 4 of the Government Code because the proposed amendment will not require local agencies or school districts to incur additional costs in complying with the proposal.  Furthermore, this regulation does not constitute a "new program or higher level of service of an existing program within the meaning of Section 6 of Article XIII B of the California Constitution."


The California Supreme Court has established that a "program" within the meaning of Section 6 of Article XIII B of the California Constitution is one which carries out the governmental function of providing services to the public, or which, to implement a state policy, imposes unique requirements on local governments and does not apply generally to all residents and entities in the state.  (County of Los Angeles v. State of California (1987) 43 Cal.3d 46.)


The proposed regulation does not require local agencies to carry out the governmental function of providing services to the public.  Rather, the regulation requires local agencies to take certain steps to ensure the safety and health of their own employees only.  Moreover, the proposed regulation does not in any way require local agencies to administer the California Occupational Safety and Health program.  (See City of Anaheim v. State of California (1987) 189 Cal.App.3d 1478.)


The proposed regulation does not impose unique requirements on local governments.  All employers - state, local and private - will be required to comply with the prescribed standard.





The Board has determined that the proposed amendments may affect small businesses.





The adoption of the proposed amendment to these regulations will neither create nor eliminate jobs in the State of California nor result in the elimination of existing businesses or create or expand businesses in the State of California.





No reasonable alternatives have been identified by the Board or have otherwise been identified and brought to its attention that would be more effective in carrying out the purpose for which the action is proposed or would be as effective and less burdensome to affected private persons than the proposed action.