• Key terms for employers in the Construction industry are defined in this section.

Guardrail system: A barrier erected to prevent employees from falling to lower levels.

Lower levels: Areas or surfaces onto which an employee can fall. Such areas or surfaces include, but are not limited to, ground levels, floors, platforms, ramps, runways, excavations, pits, tanks, material, water, equipment, structures, or portions thereof.

Low-slope roof: A roof having a slope less than or equal to 4 to 12 (vertical to horizontal).

Overhand bricklaying and related work: The process of laying bricks and masonry units such that the surface of the wall to be jointed is on the opposite side of the wall from the mason, requiring the mason to lean over the wall to complete the work. Related work includes mason tending and electrical installation incorporated into the brick wall during the overhand bricklaying process.

Personal fall arrest system: A system used to arrest an employee in a fall from a working level. It consists of an anchorage, connectors, a body belt or body harness and may include a lanyard, deceleration device, lifeline, or suitable combinations of these. As of January 1, 1998, the use of a body belt for fall arrest is prohibited.

Steep roof: A roof having a slope greater than 4 to 12 (vertical to horizontal).

Unprotected sides and edges: Any side or edge (except at entrances to points of access) of a walking-working surface, e.g., floor, roof, ramp, or runway where there is no wall or guardrail system at least 39 inches (1.0 m) high.

Walking-working surface: Any surface, horizontal or vertical, on which an employee walks or works, including, but not limited to, floors, roofs, ramps, bridges, runways, formwork and concrete reinforcing steel, but not including ladders, vehicles, or trailers on which employees must be located in order to perform their job duties.