For each risk factor ask where in the task it happens and why, since the source is what can be changed. Poor postures may come from layout, mental strain from job demands, high forces from the loads, and frequency and duration from work organisation, staffing or pace. Work area design and layout, including benches, conveyors, furniture and equipment, shapes posture, and a layout that ignores manual task risk forces bent, twisted, reaching postures or long carries. For loads, the risk comes from size, shape and weight, loads that cannot be held close, asymmetric loads, poor handles or surfaces, unstable or unwieldy loads, awkward posture while carrying for long periods, and handling people or animals whose unpredictable movements require sudden force and bring other injury risks. For tools, unsuitable ones raise force or posture demand through weight, balance, handle diameter and length, handle orientation, shock loading and impact, prolonged use and poor maintenance such as a blunt knife. There is no safe weight for all workers in all circumstances because many factors contribute.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.