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NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.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

April 3, 1996

[Name Withheld]

Dear [Name Withheld]:

This is in response to your letter of February 5, in which you asked the following questions:

Question 1. What constitutes a "floor"? If I have a flat, solid concrete slab that is laid (poured) directly on ground (earth), does that constitute a "floor" as referenced in the standard?

Answer: Neither the OSHA standard, nor the ANSI standard (A58.1-1955) from which it is derived, define floor. Therefore, we are utilizing the dictionary definitions of floor, one of which is: "That part of a room which forms its lower enclosing surface and upon which one walks." If the concrete slab to which you are referring is in a building, it would constitute a floor.

Question 2. Who is the "building official" referenced in the standard?

Answer: "Building official" refers to the local government official who is responsible for enforcing the local building codes.

Question 3. What is a "plate of approved design" as referenced in the standard?

Answer: It is the "floor loading sign" from the local building official.

Attached, for your information, is a copy of 1910.22 from the proposed standard. There is no longer a requirement for a floor loading sign; however, the employer must ensure that employees involved in warehousing or storage activities know the intended load limits. This applies to "structurally supported surfaces". The floor that you have described, i.e., a concrete slab, would not be covered under this requirement.

If you have further questions, contact [the Office of General Industry Enforcement at 202 693-1850].



John B. Miles, Jr., 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.]