(b) Walkways, runways and platforms must meet the following requirements:

1. (1) Be constructed of metal.
2. (2) Be constructed of safety treads, standard grating, or similar material with a minimum clear width of 30 inches.
3. (3) Be constructed by bolts, welds or rivets.
4. (4) Be equipped with handrails that are 42-inches high with an intermediate rail and 6-inch toeboard.

(d) A ladder that serves as a means of access to walkways, runways or platforms must be constructed:

1. (1) Of metal.
2. (2) So the rungs extend through the side members and are permanently secured to the side rails.
3. (3) So the front of the rungs have a distance of at least 30 inches from the nearest permanent object on the climbing side of the ladder.
4. (4) So the back of the rungs have a distance of at least 6 1/2 inches from the nearest permanent object.
5. (5) So there is a clear width of at least 15 inches from the centerline of the ladder on either side across the front of the ladder.