Roof and floor holes and openings in steel erection are decked over; where size, configuration or structural design prevents decking over (elevator shafts, stairwells and the like), employees are protected by covers or by guardrails put around the openings the moment they are created, with the adopted federal requirements that decking holes are not cut until immediately before they are filled or are immediately covered, covers support twice the imposed load, are secured and marked, and gaps around columns are filled.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.