A masonry wall under construction can topple before the mortar has strength. The limited access zone in 29 CFR 1926.706(a) keeps people out of where it would land.
When and where
- When: before the start of construction of the wall, per 1926.706(a)(1). Not once the wall reaches 8 ft, and not after the first course is set.
- Where: on the side of the wall which will be unscaffolded, per 1926.706(a)(3). The trap is the scaffolded side. The rule names one side, not both, and the material hoist location is irrelevant.
How big
Under 1926.706(a)(2) the zone equals the height of the wall to be constructed plus 4 ft and runs the entire length of the wall.
- 12 ft wall: 12 + 4 = 16 ft, full length.
- 10 ft wall: 10 + 4 = 14 ft.
- 9 ft 4 in wall: 9 ft 4 in + 4 ft = 13 ft 4 in.
The traps: wall height alone without the 4 ft, adding 2 ft or 5 ft instead of 4 ft, a fixed 10 ft that ignores wall height, and covering only the section laid that day. Width follows wall height; length is always the full wall.
Who may enter
Only employees actively engaged in constructing the wall, per 1926.706(a)(4). A hard hat creates no exception, and the competent person and building inspector are not the group the rule names. Admitting material-delivery laborers while excluding masons reverses the rule: the masons building the wall are exactly who may enter.
How long it stays
Under 1926.706(a)(5), for walls over 8 ft the zone remains until the bracing requirements of paragraph (b) are met. A finished 14 ft wall with no roof framing yet keeps its zone. Laying the last course, 24 hours of mortar cure and building official approval do not end it; the bracing does.
For a 10 ft wall scaffolded on its east side, the compliant setup is a 14 ft zone on the west side running the full length of the wall.