1. (1) Metal scaffolds shall be designed and constructed to support safely all loads intended to be imposed thereon, but in no case shall such scaffolds be designed or constructed to support uniform live loads of less than the following:

   1. (i) Light duty scaffolds—25 pounds per square foot.
   2. (ii) Medium duty scaffolds—50 pounds per square foot.
   3. (iii) Heavy duty scaffolds—75 pounds per square foot.

2. (2) Metal scaffolds designed and constructed for particular types of work shall support uniformly distributed live loads in accordance with the following:

   1. (i) Stone masons—75 pounds per square foot.
   2. (ii) Stone setters (no stone on scaffold)—25 pounds per square foot.
   3. (iii) Bricklayers—50 pounds per square foot.
   4. (iv) Stucco applicators—50 pounds per square foot.
   5. (v) Lathers and plasterers—50 pounds per square foot.
   6. (vi) Carpenters—25 pounds per square foot.
   7. (vii) Miscellaneous (no material on scaffold)—25 pounds per square foot.

3. (3) In addition to such live loads, metal scaffolds shall be designed and constructed to support the dead loads, such as platforms, frames, safety railings and other members.

   (e) Safety railings.

   Safety railings constructed and installed in compliance with this Part (rule) shall be provided for every metal scaffold.

   (f) Access.

   Ladders, stairs or ramps shall be provided for access to and egress from the platform levels of metal scaffolds which are located more than two feet above or below the ground, grade, floor or other equivalent level.

   (g) Footings.

4. (1) Footings for metal scaffolds shall be sound, rigid and capable of supporting the maximum design loads of such scaffolds without settlement or deformation. Such footings shall be secure against movement in any direction and shall have sufficient area to properly transfer the vertical post or end frame loads of the scaffolds to the ground, grade or equivalent surface without causing any unsafe condition.
5. (2) Metal base plates of not less than 16 square inches in area by one-eighth inch in thickness shall be provided for the tubular ends of posts and for the legs of end frames which are in bearing contact with the footings or other supporting surfaces.

6. (3) Where the ground, grade or other supporting surface of a metal scaffold is not level, screw jacks or adjustment jacks shall be used to support the tubular posts or end frames of the scaffold so that the scaffold platform bearers are level. Such adjustment jacks shall be so positioned that the threaded sections do not extend beyond the frames or parts more than 12 inches.

   (h) Tie-ins.

7. (1) Every metal scaffold shall be securely tied into the building or other structure at intervals not to exceed 30 feet horizontally and 26 feet vertically.
8. (2) Ties to any window cleaners' anchors are prohibited.

(a) Application of this section.

This section applies to all scaffolds constructed of metal except mobile types.

(b) Special approval required.

Any metal scaffold erected after June 1, 1972 to a height exceeding 125 feet above the ground, grade or equivalent surface shall not be placed in service until such scaffold has been granted a special approval. The plans and specifications for any such scaffold shall be submitted to the board for such approval.

(c) Strength and factor of safety.

The total of live and dead loads imposed on any scaffold assembly shall not exceed one-quarter of the ultimate strength of the members as determined by actual test.

(d) Minimum uniform live loads.