Warning Lines for Construction Activities

Warning lines shall be erected around all sides of the roof work area at least 6 feet from the roof edge when mechanical equipment is not being used. When mechanical equipment is being used, the warning lines shall be erected not less than 6 feet from the roof edge which is parallel to the direction of mechanical equipment operation, and not less than 10 feet from the roof edge which is perpendicular to the direction of mechanical equipment.

Warning lines shall consist of rope, wire, tape, or chain that meets the following:

• Has a minimum breaking strength of 500 lbs. for construction activities (and 200 lbs. for designated areas).
• Is installed so its lowest point, including sag, is between 34 inches and 39 inches above the walking-working surface.
• Stanchions are capable of resisting, without tipping over, a force of at least 16 lbs. (applied horizontally against the stanchion, 30 inches above the walking surface, perpendicular to the warning line, and in the direction of the floor, roof, or platform edge).
• Is supported in such a manner that pulling on one section of the line will not result in slack being taken up in adjacent sections causing the line to fall below 34 inches.
• Is flagged every 6 feet with high visibility material.
• No employee shall be allowed in the area between the roof edge and the warning line unless the employee is performing roofing work in the area.

Points of access, material handling areas, storage areas, and hoisting areas shall be connected to the work area by an access path formed by two warning lines. When the point of access is not in use, a warning line shall be placed across the path near the work area, or the path may be offset so that a person cannot walk directly into the work area.