The employer's first obligation is to eliminate risks from hazardous substances at the workplace, as far as reasonably practicable. If elimination is not reasonably practicable, it must reduce the risk, as far as reasonably practicable, by substituting a less hazardous substance or a less hazardous form, isolating the source of exposure, using engineering controls, or a combination of those. Only for the risk that remains after those steps may it add administrative controls, and only for the risk left after that may it rely on suitable personal protective equipment for employees at risk. Consultation with employees and any health and safety representative applies to decisions on these measures (Part 4 of the Act, r 21). The duty supports section 21 of the Act.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.