For these reasons the action list leads. in most cases, to proposals for a more detailed investigation. To draw the limits too tightly would lead to an undue expense in changing jobs without any guarantee that those still within the boundary would be safe. Hence the use of RULA will give a priority order for jobs which should be investigated, while the magnitude of the individual posture scores and the muscle use or exerted force scores indicate which aspects of the postures are likely to be those where trouble will be expected. It should be noted that while RULA provides a guide to the risks associated-with work-related musculoskeletal injuries there is no substitute for some understanding of occupational ergonomics if sound decisions are to be made on the basis of the information, when redesigning operations