(1) Openings cut in a floor must extend the full span of the arch between supports.

(2) Before demolishing any floor arch, you must remove debris and other material from such arch and other adjacent floor area. You must provide for planks not less than two inches by 10 inches in cross section, full size undressed, and must be used by employees to stand on while breaking down floor arches between beams. You must locate such planks so as to provide a safe support for the workers should the arch between the beams collapse. The open space between planks must not exceed 16 inches.

(3) You must provide safe walkways, not less than 18 inches wide, formed of planks not less than two inches thick if wood, or of equivalent strength if metal, and ensure that they are used by workers when necessary to enable them to reach any point without walking upon exposed beams.

(4) You must install stringers of ample strength to support the flooring planks, and the ends of such stringers must be supported by floor beams or girders, and not by floor arches alone.

(5) You must lay planks together over solid bearings with the ends overlapping at least one foot.

(6) When floor arches are being removed, you must not allow employees in the area directly underneath, and you must barricade such an area to prevent access to it.

(7) You must not start demolition of floor arches until they, and the surrounding floor area for a distance of 20 feet, have been cleared of debris and any other unnecessary materials.