A standard guardrail shall consist of a 2 inch by 4 inch (51 by 102 mm) wood top rail or equivalent capable of withstanding, without failure, a force applied in any downward or horizontal direction at any point along its top edge of at least 200 pounds (90.7 kg). The guardrail shall be not less than 3 feet (914 mm) nor more than 3 feet 6 inches (1067 mm) above the platform and there shall be a 1 inch by 4 inch (25 by 102 mm) wood intermediate rail midway between the top rail and the floor or standard toeboard, both supported by 2 inch by 4 inch (51 by 102 mm) wood posts spaced not more than 8 feet (2438 mm) apart.
To provide necessary openings for intermittent operations one or more sections of a required railing may be hinged or supported in sockets. When supported in sockets, rails shall be so constructed that they cannot be jolted out. A button or hook may be used to hold the rail in a fixed position. Substantial chains or ropes may be used to guard such openings in standard railings. Where so used, the chains or ropes shall be taut at the same height as the rails of the standard railing.
In lieu of wood construction, posts and rails may be constructed of at least 11/4 inch (32 mm) diameter standard pipe of at least 2 inch by 21/4 inch (51 by 57 mm) angles. Spacing of rails and posts shall be as required above
Where a toeboard is required, it shall be at least 5 1/2 inches (140 mm) high and constructed of metal, wood, or other substantial material. It shall be installed along the edge of the floor, opening, platform, ramp, or runway. Such standard toeboard shall be securely fastened to the posts and installed so that no open space exists between the floor and the standard toeboard.