Same number, different wording
The 6 ft wording changes by paragraph of 29 CFR 1926.501.
- Edges, (b)(1): unprotected sides and edges 6 ft or more above a lower level.
- Holes, (b)(4)(i): holes more than 6 ft above lower levels.
Treating "more than" and "or more" as the same is a listed error. Copying the edge wording onto holes is the trap. "At any height" is not the hole rule, and more than 10 ft is the scaffold trigger in 1926.451(g)(1), not Subpart M.
Below 6 ft: dangerous equipment, (b)(8)(i)
Employees less than 6 ft above dangerous equipment must still be protected from falling into or onto it. An ironworker 4 ft above operating equipment needs protection. Applying the 6 ft trigger uniformly misses this rule. Protection is mandatory, not left to a competent person's judgment.
Overhand bricklaying, (b)(9)(ii)
Protection is required when the mason reaches more than 10 in below the level of the walking/working surface. Other small numbers are traps from elsewhere:
- 6 in is the scaffold platform end extension over its support.
- 18 in is the maximum overhang for scaffold platforms longer than 10 ft.
- 39 in is the inside-sill threshold for wall openings.
Wall openings, (b)(14)
Covered when both conditions hold:
- The outside bottom edge is 6 ft or more above lower levels.
- The inside bottom edge is less than 39 in above the walking/working surface.
An opening 20 ft above ground outside with a 30 in inside sill meets both. A 42 in sill is not less than 39 in, and a 5 ft outside drop is below 6 ft.
Low-slope roofs, (b)(10)
On a low-slope roof, a warning line may be combined with a guardrail, safety net, personal fall arrest system or safety monitor. A safety monitor alone is allowed only on roofs 50 ft (15.25 m) wide or less. An 80 ft roof needs a combination. There is no 100 ft limit.