Tips On Using A Warning Line System

Temporal warning lines are used to define work areas when working on top of roofs and are recommended for use together with fall protection anchor and other systems according to OSHA fall protection guidelines. Warning lines are made of ropes, wires, or chains and supporting stanchions.

Basically, they are visual marks to remind you of where to go and not to go when working on top of the roof. They are not permanent, meaning they can be changed as requirements change. The other category is permanent warning lines that are installed permanently but serve the same purpose.

Warning line systems, whether temporal or permanent do not restrain workers and they can still be broken by the workers to access dangerous areas. They also do not arrest falls, which is the reason you should use them together with OSHA fall protection systems such as fall protection anchors and fall restrain systems.

It is possible to read the guidelines and install the line on your own at your work site, especially if you are familiar with the technical terms. However, some people are not familiar with these terms and it can be difficult to erect a warning line system. Sometimes you might try but errors are eminent, which only endangers your workers at the site or people using the path. A qualified fall protection company can be contacted to guide on the use of warning line systems, horizontal lifeline, fall restrain systems or fall protection anchors.

In design, these systems basically consist of cables threaded through vertical posts with a 12 lb. tip-over threshold spaced at 40’ intervals. The cable is positioned 34"-39" above the roof surface and flags are spaced every 6 inches. Sand bags can be used to maintain the vertical posts in position if there are high winds or incremental weather.

OSHA regulation state that the warning line system should be erected 6 feet from the roof edge when there is no equipment being used. When there is equipment being used, the line should be installed 6 feet from the roof edge parallel to the direction of mechanical equipment operation and not less than 10 feet from roof edge perpendicular to the direction of the equipment operation. The line's lowest point should be not less than 34 inches from the working surface and not more than 39 inches from the working surface.

A highly visible material should flag the waning line at each 6 feet interval.

Horizontal lifelines and warning lines are erected around all sides of the roof work area.

Two warning lines should be used to form an access path that connects points of access, materials handling areas, storage areas, and hoisting areas.

If there is a path that someone can use to access the work area, a rope, wire, chain or other barricade will be used to block the path and prevent access. The blockage is placed across the path at the point where the said path intersects the warning line.