Stairway rules for scaffold step unit towers

October 27, 1992

Mr. R. C. Mocny,
Vice President
Engineering and Manufacturing
Patent Scaffolding Company
[Recipient address omitted]
Dear Mr. Mocny:

This is in response to your letter of July 21 in which you request a clarification of the application of Subpart X -- Stairways and Ladders, to scaffold step unit towers and whether or not a 1976 letter of interpretation from the Occupational Safety and Health Administration (OSHA) is still valid. This is also in response to your follow-up letter of October 6 in which you provided additional information about your products.

The provisions of Subpart X -- Stairways and Ladders apply to scaffold step unit towers when they are used for access to locations other than scaffold platforms. As you know, 1926.1052(a)(1) requires such stairways to "have landings of not less than 30 inches in the direction of travel and extend at least 22 inches in width at every 12 feet or less of vertical rise." These requirements appear to be met by the configuration labeled "parallel construction" on page 11 of your publication titled Safety Rules and Instructions # 508R.

Of course, when scaffold step unit towers are used for scaffold platform access, then the requirements and interpretations of 1926.451[(e)(4)] apply during construction.

If you have any further questions, please do not hesitate to contact myself or [Mr. Noah Connell] of my staff at [(202) 219-7207].

Sincerely,
Roy F. Gurnham, Esq., P.E.
Director
Office of Construction and Maritime
Compliance Assistance