Spinal compression tolerance limits for the design of manual material handling operations in the workplace.

Spinal compression tolerance limits (SCTL) have been widely used by ergonomists in setting work tolerance limits for manual materials handling (MMH) operations. Thus, the effect of personal and experimental factors on spinal compression tolerance limits (SCTL) is reviewed with the aid of regression and correlation analyses performed on data compiled from the published literature. Tables of SCTL from various sources utilizing large number of specimens and personal factors are presented so that they can be accessed by ergonomists easily. Integrated biomechanical guidelines based on SCTL are provided for the design of MMH operations in the workplace. It is suggested that, in order to reduce the probability of MMH injuries, biomechanical tolerance limits should be set at the damage load instead of the load at fracture. The damage load is the weight which causes the first gross signs of damage such as tissue fluid and blood. An algorithm is described to demonstrate the use of a biomechanics approach to the design of MMH operations.