(a) When elevator scaffold jacks are used for the installation of elevator hoistway doors, such scaffold jacks shall be constructed and installed in compliance with this Part (rule).

(b) The platforms of such scaffolds shall consist of planks at least equal in strength to No. 1 grade fir. Such planks shall be at least two inches thick full size. Such planks shall be supported by scaffold brackets or jacks constructed of spruce or plywood at least three-quarters inch by five inches in size or of metal of equivalent strength.

(c) Such jacks shall be constructed and installed in any hoistway by being tightly wedged between the guide rails and the elevator door sill. There shall be a notch at least one and one-half inches by one and one-half inches in the lower horizontal member of each jack at which point such jack shall rest on the door sill. A plank, at least two inches thick full size, shall be placed on the lower members of the jack and notched to fit tightly against the front vertical members to prevent any inward movement of the jacks. Such planks shall be bolted to the jacks by means of angles three inches by three inches by one-quarter inch in size. The first plank of the main scaffold platform shall be bolted similarly to the jacks. At the points where the jacks rest against the guide rails, “C” clamps shall be used to prevent dislodgment. “C” clamps shall also be used to fasten two-inch by four-inch guard rails to the guide rails. Where it becomes necessary to prevent horizontal movement, cleats shall be nailed to the platform planks to block such planks against the guide rails and/or hoistway walls.

(d) Every person working from, installing or dismantling such scaffolds shall be provided with and shall use an approved safety belt or harness properly secured in compliance with this Part (rule).