Citations for violating scaffolding requirements consistently make it onto OSHA’s annual Top 10 list. The requirements are in 29 CFR 1926.451(a) through (h). In this Part 2, we look at the scaffold platform construction requirements [29 CFR 1926.451(b)].
The first rule listed is aimed at eliminating gaps that people could step through. On every working level, each platform must be fully planked or decked between the front uprights and the guardrail supports [29 CFR 1926.451(b)(1)]. You’re allowed a maximum of 1 in. between planks, but there are a couple of exceptions to this rule.
The second rule is aimed at having a wide enough platform that people can safely stand on it. The minimum width is 16 in. [29 CFR 1926.451(b)(2)]. There are a couple of exceptions here, too. For example, maybe the space itself is only 15 in. wide. You’re not going to fit a 16-in.-wide platform into it.
The third rule is aimed at not having people lean out into space. The front edge can’t be more than 16 in. from the face of the work [29 CFR 1926.451(b)(3)]. This also has a couple of exceptions.
Rule number four requires each end of a platform to extend at least 6 in. over the centerline of its support [29 CFR 1926.451(b)(4)]. There are exceptions to this also, for example if the boards are cleated or secured with hooks.
The fifth rule puts a constraint on the fourth rule. Imagine extending the board farther and farther out from its support. The lever arm increases in length, which is not good. So the maximum length out for a platform of 10 ft or less in length is 12 in. If the platform is longer than 10 ft, the limit is 18 in. [29 CFR 1926.451(b)(5)].
You’ll find six more rules in this subsection. In summary:
- Abutted planks must have their own supports, as planks cannot share supports simply because they abut.
- Overlaps can occur only at supports.
- There is a definite board laying order when a scaffold changes direction (such as turning a corner).
- Coatings and finishes cannot obscure the surfaces of wooden planks.
- Don’t intermingle components from different manufacturers unless they fit without force or modification.
- Don’t use scaffold components made of dissimilar metals (an exception exists).
It is a good idea to train scaffold users on these requirements, even if they do not erect scaffolding. That training will give them the ability to inspect the scaffolding they use for construction errors. Those errors can then be corrected, rather than described in a fatality report.
