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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 http://www.osha.gov.

October 31, 1979

Mr. Herbert W. Schneider
Rossman and Partners Architects
4601 E. McDowell Road
Phoenix, Arizona 85008

Dear Mr. Schneider:

This is in response to your recent letter dated August 16, 1979, addressed to Mr. Thomas Seymour, concerning OSHA fixed ladder requirements. Your letter was forwarded to this office for response.

29 CFR [1910.27(d)(1)(vi)], requires ladder wells to have a clear width of at least 15 inches measured each way from the centerline of the ladder. Smooth-walled wells shall be a minimum of 27 inches from the center-line of rungs to the well wall on the climbing side of the ladder. Where other obstructions on the climbing side of the ladder exist, there shall be a minimum of 30 inches from the center line of the rungs.

The above requirement was taken from the American National Standards Institute A14.3-1956, safety code for fixed ladders and promulgated as an OSHA standard. The existing standard does not provide a maximum distance and the 37 inches you provided would appear to be logical and proper for the design of the ladder well.

The latest American National Standards Institute A14.3-1974 safety requirements for fixed ladders requires the inside face of the well in the climbing side of the ladder shall extend not less than 27 inches or more than 30 inches from the center line of the step or rung. The inside clear width of the well shall be a nominal 30 inches.

The ladder you installed in the auditorium at Tempe, Arizona, with access being made as shown in [Figure D-8] in 29 CFR 1910.27 appears to comply with our fixed ladder requirements. However, the flared top 3 feet 6 inches of the ladder from the 1 foot 6 inches width to 2 feet with the rungs omitted are not required by OSHA unless they are through ladder extensions.

Your interest in the Occupational Safety and Health Act and the safety and health of American workers is deeply appreciated. If we may be of further assistance, please feel free to call or write.


Grover C. Wrenn Director,
Federal Compliance and State Programs