A risk assessment should be done when it is uncertain how a hazard may cause injury or illness, when the work involves several hazards and their interaction is not understood, and when workplace changes may affect how well controls work. It can also identify which workers are exposed, what sources and processes cause the risk, what controls are needed and whether existing controls are effective.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.