A PCBU must manage the risk of a person falling from one level to another where the fall is reasonably likely to injure that person or anyone else. The first control, as far as reasonably practicable, is to carry out the work at ground level or on a solid construction, meaning an area with a surface able to carry everyone and everything on it, barriers around its edges and openings, an even and easily negotiated surface and gradient, and safe entry and exit. If the fall risk cannot be eliminated it must be minimised by a safe system of work using, in this order and as far as reasonably practicable: first a fall prevention device (for example guardrails or temporary work platforms); next a work positioning system (for example industrial rope access); and last a fall arrest system (for example catch platforms). A lower option may be used only if the one above it is not reasonably practicable.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.