Openings cut in a floor must span the full arch between supports. Before any floor arch is demolished, debris and other material must be removed from it and the adjacent floor area. Employees breaking down floor arches between beams must stand on full size undressed planks with a cross section of at least 2 by 10 inches, positioned to support them safely if the arch collapses, with no more than 16 inches of open space between planks. Where needed so workers can reach any point without walking on exposed beams, safe walkways at least 18 inches wide must be provided and used, made of wood planks at least 2 inches thick or metal of equal strength. Stringers strong enough to support the flooring planks must be installed with their ends carried by floor beams or girders, not by floor arches alone, and planks must be laid side by side on solid bearings with their ends overlapping at least 1 foot. While floor arches are being removed, nobody may be in the area directly below, which must be barricaded. Arch demolition may not start until debris and any other unneeded material have been cleared from the arches and from the floor for 20 feet around them.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.