OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

July 17, 1985

Mr. Richard L. Stewart
Executive VP, Operations
Steeplejac, Inc.
870 Decatur Avenue
Minneapolis, Minnesota 55427

Dear Mr. Stewart:

This is in response to your letter of June 10, 1985, in which you request clarification and the applicability of regulations pertaining to exterior building work platforms used for window washing.

The Occupational Safety and Health Administration (OSHA) standards do not specify requirements to which buildings must be constructed. The Occupational Safety and Health Act of 1970 (the Act) requires employers to: (1) furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees; and (2) comply with OSHA standards. Therefore, employers must comply with existing OSHA standards where they are applicable to the circumstances. However, the employer is not limited only to those workplace procedures for which an OSHA standard is applicable. In any event, the employer remains obligated under the Act to provide workplaces free of recognized hazards. A copy of the Act is enclosed for your reference.

What this all means to individuals in the process of designing and constructing a building which will require exterior building maintenance equipment is the following:

1. Installation of exterior building maintenance equipment described by existing OSHA standards must provide for at least the specified minimum employee safeguards. Temporary installations are regulated by 29 CFR 1910.28, and permanent installations by 29 CFR 1910.66. Presently, there is no restriction upon the maximum height of either two-point suspension scaffolds or powered platforms.

2. Installation of new system concepts, to which existing OSHA standards are not applicable, must be constructed to assure employee safety and must be free of recognized hazards that are causing or are likely to cause death or serious physical harm to employees.

The architects, engineers, design consultants, and owners may select any form of exterior building maintenance equipment that is appropriate. It is not the intent of OSHA to stifle imaginative ingenuity in regard to the use of new concepts for exterior building maintenance; however, the legal obligation of the Act requires that the safety of exposed employees must be assured.

Design codes for exterior building maintenance equipment may be specified by various State and local governments. Where local codes are in effect, they are generally more specific and more stringent than applicable OSHA regulations. They are usually restricted to design and construction parameters and stipulate design constraints. Compatibility with OSHA regulations is seldom an issue. It is prudent to ascertain the local building and safety requirements before considering the impact of OSHA regulations upon a new installation.

Most new buildings and major alterations of older buildings are fitted with exterior building maintenance equipment which complies principally with ANSI A120.1 or ANSI A10.8. Other new imaginative concepts beyond the scope of even the current ANSI standards may also be viable considerations.

OSHA issued an Instruction STD 1-3.3, dated November 1, 1982 (copy enclosed), which specifically addresses an alternative system describing intermittent stabilization of suspended powered platforms regulated under 29 CFR 1910.66. (29 CFR 1910.66 was adopted from ANSI A120.1.) The alternative described is only for use with powered platforms described by 29 CFR 1910.66 and does not permit this option for use with suspended scaffolds regulated under 29 CFR 1910.28. (29 CFR 1910.28 was adopted from ANSI A10.8.) Furthermore, a documented engineering analysis which substantiates the safety aspects of the alternative system is required to be provided by a professional engineer knowledgeable in the field.

A copy of the proposed rule for powered platforms is enclosed. Should you wish to provide technical input to OSHA with regard to specifics, such as height, we suggest you communicate with the Directorate of Safety Standards Programs. You may contact:

Barry J. White, Director
Directorate of Safety Standards Programs
U.S. Department of Labor - OSHA
Room N-3605
200 Constitution Avenue, N.W.
Washington, D.C. 20210
Telephone: (202) 523-8061

If we may be of further assistance, please contact us.


John B. Miles, Jr., Director
Directorate of Field Operations