November 8, 2000

In your memos of September 27 and October 18, you ask if Alum-A-Pole pump jack scaffolds must have bracing on the bottom of the scaffold, as is specifically required under 29 CFR 1926.452(j)(2). You state that the manufacturer claims that if the pump jack poles are plumb the weight of the scaffold will prevent the scaffold from moving. Included with your October 18 memo are test data supplied by the manufacturer.

Section 1926.452(j)(2) states that "poles shall be secured to the structure by rigid triangular bracing or equivalent at the bottom, top, and other points as necessary...." During the rulemaking for this standard, in the Notice of Proposed Rulemaking, OSHA asked the public to comment on Issues 9 and 22: whether OSHA should remove the requirement for bottom braces on pump jack scaffolds. Comments on this issue were received, and in the final rule's preamble, the issue was addressed (see page 46,083 of volume 61 of the Federal Register, dated Friday, August 30, 1996). Some commenters asserted that the weight of the scaffold would prevent the base from being displaced. This was rebutted by a commenter who stated that the "bottom brace should remain for poles, [because that part of the scaffold] is the one part that is easiest to hit and move." The commenter added that the "bottom brace seems like the one that is needed the most,...." In addition, the National Institute for Occupational Safety and Health and the Advisory Committee for Construction Safety and Health studied the issue, and both came to the conclusion that the bottom brace needs to be retained. Consequently, OSHA decided not to allow an exception to the brace requirement (or equivalent means) for pump jack scaffolds:

"Based on its review of the comments, OSHA has determined that employers do need to brace the bottom of the support pole to keep it in place, but that it is not necessary to specify the use of a rigid triangular bottom brace. Other methods, such as anchoring the pole to the ground, would provide equivalent support. Therefore, the final rule requires, as did the proposal, that pumpjack poles be braced at the bottom by triangular bracing or equivalent means."

The standard permits an "equivalent means" of bracing to triangular bracing. However, both the definition of bracing in the standard and the example of equivalent means in the preamble show that relying on the weight of the scaffold to prevent movement of the pole support is not an equivalent means. In §1926.450(b), the standard defines a brace as "a rigid connection that holds one scaffold member in a fixed position with respect to another member, or to a building or structure." The example of an equivalent means in the preamble is the anchoring of the pole to the ground. In both cases, the pole is physically attached — either to the building or to the ground. Since use of scaffold weight alone does not include a physical connection, it is not an "equivalent means."

Finally, the test data indicates that imparting vertical loads on the scaffold did not cause the pole supports to kick-out. However, as noted above, part of the reason that an exemption was disallowed for pump jack scaffolds was the concern that the bottom of the pole "is the one part that is easiest to hit and move." The test data submitted does not address the ability of the pole support to resist such horizontal forces.

[Corrected 6/2/2005]