Steep Residential Roof: Warning Line and Safety Monitor
Summit Roofing is re-roofing a two-story house with a 9:12 pitch and an 18-foot eave. Four workers are on the roof. The foreman set up a warning line about 6 feet back from the eave and assigned a safety monitor, but the monitor is also running a nail gun and working with the crew. No guardrails, safety nets, or personal fall arrest systems are in use. The foreman tells the OSHA compliance officer, 'This is residential construction, so we can use alternative fall protection. The warning line is 6 feet from the edge, which is what OSHA requires.' The roof is steep, and workers are walking backward down the slope to position shingles.
1. Is the warning line plus safety monitor acceptable fall protection for this roof? Explain.
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No. For residential construction, fall protection is required at 6 feet, and the standard expects conventional systems: guardrails, safety nets, or personal fall arrest systems. Alternative measures are allowed only when the employer can show that conventional fall protection is infeasible, and then only under a written fall protection plan.
This is a 9:12 roof, which is steep. A warning line is a warning, not a fall-arrest system, and it is not designed to arrest a worker sliding down a steep slope. The safety monitor is also disqualified because the monitor is running a nail gun and working with the crew; a safety monitor must be able to watch the workers and have no other duties that interfere.
2. What must Summit do before work resumes, and what if the employer claims conventional fall protection is infeasible?
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Before work resumes, Summit should install a conventional system: guardrails at the perimeter, safety nets, or personal fall arrest systems with adequate anchors, compatible connectors, and a rescue plan. Workers need training on the system and on the fall hazards.
If Summit claims conventional fall protection is infeasible, a qualified person must develop a written fall protection plan under 1926.502(k). The plan must identify the locations where conventional systems are infeasible, explain why, describe the alternative measures, and provide for training and re-evaluation. The employer cannot simply declare infeasibility after the inspection and keep using a warning line and a working safety monitor.
3. The foreman says the warning line is '6 feet from the edge, which is OSHA standard.' How do you respond in a way that addresses the underlying hazard?
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The 6-foot warning line is associated with low-slope roof provisions, not with steep residential roofs. Even where a warning line is permitted, it is a warning barrier, not a perimeter guardrail or fall-arrest system; it keeps workers away from an edge but does not stop a fall.
On a 9:12 roof, a slip can become a slide and then a fall before the worker reaches the warning line. The relevant question is not whether the line is 6 feet from the edge, but whether the system will prevent a fall from 18 feet. Here it will not.