Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

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

November 12, 1992

Mr. Craig B. Williams
Vice President,
Marketing and Sales
M.A. Industries, Inc.
P.O. Box 2322
Peachtree City, Georgia 20369

Dear Mr. Williams:

Thank you for your inquiry of July 8, addressed to Rolland Stroup, Chief of the Division of Safety Abatement Assistance, requesting an interpretation of the applicability of the exception note at 29 CFR 1910.23(c)(12) in the "Walking and Working Surfaces and Personal Protective Equipment (Fall Protection Systems); Notice of Proposed Rulemaking." Please accept our apology for the delay in responding.

The American National Standards Institute's (ANSI) A14.3-1956, Safety Code for Fixed Ladders, is the source standard for 29 CFR 1910.27, the current Occupational Safety and Health Administration (OSHA) standard on fixed ladders. There is no provision in current OSHA standards covering the construction or use of your newly designed ladder. Therefore, your ladder was reviewed with respect to the general duty clause (Section 5(a)(1)) of the Occupational Safety and Health (OSH) Act. Section 5(a)(1) requires that each employer shall 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.

The toe clearances of 4.5 and 7 inches (11.4 and 17.8 cm) for permanently fixed ladders were derived from ANSI A14.3 - 1956, section 5.4. To accommodate existing ladder installations at unavoidable obstructions including structural beams, foundation walls, air ducts, water pipes, etc., the 4.5 inch (11.4 cm) clearance was included in the April 10, 1990 Notice of Proposed Rulemaking for Subpart D, Walking and Working Surfaces and Personal Protective Equipment. The aforementioned clearances, which are the same as the basis for the current standard, are applicable to existing permanent ladder installations in workplaces including manhole base ladders. Your hanging manhole base ladder, as described in your letter, would fit into the proposed exception of allowing a reduced toe clearance to 4.5 inches (11.4 cm) to better line up with the projection of the manhole steps and to provide adequate climbing space in a manhole enclosure.

To be in compliance with the proposed OSHA standard, the manhole steps used to support your ladder must be capable of supporting their maximum intended load, (see proposed rule 1910.24, "step bolts and manhole steps" for additional guidance), and the ladder must be secured in position (see proposed rule 1910.23(b), "general requirements"). Neither the current nor proposed standards address ladders made of synthetic materials. However, to be in compliance with the general duty clause of the OSH Act, ladders made of synthetic materials must be as safe as wood or metal ladders which comply with OSHA standards. Factors such deterioration of material over time, strength and durability must be given consideration.

Thank you for your interest in occupational safety and health. If you have additional questions pertaining to proposed OSHA safety standards, please direct them to [the Directorate of Science, Technology and Medicine at 202 693-2300].



Roger A. Clark, Director
[Directorate of Enforcement Programs]

[Corrected 4/4/2005.

Note: On April 10, 1990 OSHA published proposed revisions to Walking and Working Surfaces; Personal Protective Equipment (Fall Protection Systems); Notices of Proposed Rulemaking; Slips; Falls; Trips in Federal Register 55:13360-13441. It is available electronically only as an abstract. On May 2, 2003 OSHA reopened the rulemaking record on the proposed revisions to Walking and Working Surfaces and Personal Protective Equipment (Fall Protection Systems). It was re-published in its entirety in Federal Register 68:23527-23568 and is available electronically.]