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.


January 10, 1979

Mr. Dee Walters
National Sales Manager M.A. Industries, Inc.
Kelly & Dividend Road
Peachtree City, Georgia 30269

Dear Mr. Walters:

This is the final response to your letter dated September 25, 1978, and your request for clarification of OSHA guidance concerning the uniform spacing of steps or rungs in sanitary and storm sewer manholes.

A thorough review of the uniform spacing for steps or rungs used in sanitary and storm manholes has been completed. On December 29, 1978, this office issued OSHA Instruction STD 1-1.9, (copy enclosed). This Instruction supersedes OSHA Instruction STD 1-1.2, by including spacing dimensions for individual rungs or steps meeting good engineering practices as you requested.

Thank you for your continued interest in occupational safety and health. If I can be of any further assistance, please feel free to contact me.


John K. Barto,
Chief Division of Occupational Safety Programming

[Corrected 6/19/07]