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.

February 7, 2000

K. Doyle Taylor
Safety Coordinator
Anheuser-Busch Companies, Inc.
Executive Offices
One Busch Place
St. Louis, MO 63118-1852

RE: Subpart "L" - Tank Scaffolding; methods of overlapping scaffold planking

Dear Mr. Taylor:

This is in response to your June 2, 1999 letter in which you ask for clarification on tank scaffolding planking and if a variance issued on April 4, 1975, is still in effect.

In the diagram that you sent to our office, you show two ways of installing end-to-end rows of scaffolding planks. In both methods the ends of each scaffolding plank are overlapped with the ends of the adjacent planks. In one drawing, the planks are laid so that one end of each plank is on the bottom of an overlap and the other end is on the top of an overlap (using this method the planks are slightly tilted). The second drawing shows the planks laid so that both ends of each plank are either on the bottom or the top of their respective overlaps (using this second methods each plank lays flat). Your question is whether both ways are acceptable.

Section 1926.451(b)(7) states, "on scaffolds where platforms are overlapped to create a long platform, the overlap shall occur only over supports, and shall not be less than 12 inches (30 cm) unless the platforms are nailed together or otherwise restrained to prevent movement." The standard does not specify whether both ends of each plank must overlap the same way. Therefore, both methods are acceptable ways of overlapping planks.

During a telephone conversation, you indicated that you believed that a variance issued on April 4, 1975, for tank scaffolds discussed how scaffold planks should be overlapped, as per your first question. After reviewing the variance and the scaffolding standard that was in effect in 1975, we have determined that the variance did not address this issue. It merely noted that, "all planks shall be secured from movement or overlapped in accordance with §1926.451(a)(12)." Like the current standard, the 1975 standard did not address this issue (section 1926.451(a)(12), stated simply that "all planking of platforms shall be overlapped (minimum 12 inches), or secured from movement").

You also ask whether that variance is still in effect. Since OSHA has never modified or revoked it, under section 6(d) of the Occupational Safety and Health Act, it is technically still in effect. However, the scaffold standard for which that variance was issued is no longer in effect; a new scaffold standard was issued in September 1996. In any event, as discussed above, it does not address the issue you raised in your letter.

If you require any further assistance, please do not hesitate to contact us again by writing to: Directorate of Construction - OSHA, Office of Construction Standard and Compliance Assistance, Room N3468, 200 Constitution Avenue N.W., Washington D.C. 20210.


Russell B. Swanson, Director
Directorate of Construction