No live work is allowed in a hazardous area, since work on wiring and equipment could cause explosion or fire. Ignition sources to consider include static from wool or synthetic clothing, personal items and electronics not certified for the area (phones, car keys, torches, lighters), uncertified tools, test equipment and instruments, and spark or heat producing actions such as hot work, drilling, grinding, steel striking concrete, some metal-on-metal impacts and rubbing plastics. Ignition sources should be kept out of hazardous areas and spark or heat producing work should not be done unless the absence of an explosive atmosphere has been confirmed; AS/NZS 60079.14 and 60079.17 cover competency and equipment, and ignition sensitivity varies by substance (hydrogen very sensitive to static, ammonia not).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.