What course of action should you take if all 3(three) "Special Hazards" are present in your building? I realize that if a substance is both an oxidizer and reactant to water you put -W-(lets pretend the line continues through the W) in the quadrant and OX below or next to the quadrant for an oxidizer, but in the lab we also have Nitrogen gas, which is (per my understanding) considered an simple asphyxiant(SA). So for the entrances to the building/room/anywhere I would use the composite method as described in 220.127.116.11* to warn emergency personnel would I merely include all 3 acronyms? Which of the symbols should be in the quadrant vs next to the quadrant? Would I be better directed to ask the local fire-marshall?