Where grinding, sieving or another process may release dust liable to explode on ignition, all practicable steps prevent an explosion by enclosing the plant, removing or preventing accumulations of escaped dust and excluding or effectively enclosing possible ignition sources, and, unless the plant can withstand the explosion pressure, by fitting chokes, baffles, vents or equally effective appliances to restrict its spread and effects. No plant, tank or vessel containing or having contained an explosive or inflammable substance is welded, brazed, soldered or heat-cut until all practicable steps remove the substance and its fumes or render them non-explosive and non-inflammable, and no such substance is allowed back in until the metal has cooled enough to avoid igniting it (the Commissioner may exempt by certificate). All electrical apparatus, fittings and conductors are big and powerful enough for their purpose and are built, installed, protected, operated and maintained so that, so far as reasonably practicable, they create no danger.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.