A test for monitoring industrial injuries, based on a statistical approach, was presented. Information typically contained in medical surveillance systems was incorporated with additional information about injury costs into the test to control injury and severity rates on a particular operation. A case example of monitoring injuries on an assembly operation was presented. Injury data for a period of 4.75 years were obtained. A large number of musculoskeletal injuries were reported. A baseline incidence rate was estimated. Histograms of lost time and severity cost for the assembly operation were constructed. The average injury cost was determined. Parameters were measured that model the occurrence of injuries on an operation. The model had two main components, an "in control" and an "out of control" portion. When an unacceptable incidence rate occurred, a search for the cause was made, the situation was corrected, and the rate returned to or below the acceptable level. A brief description of the operation hazards for the assembly operation was provided. Parameter estimates for the case example were summarized. Completion of the injury monitoring test, by tracking the exposure time between injuries in units of 100 employee years, was described. The test sensitivity was examined. The mathematical expression for the total cost per exposure hour was presented.