Machine safety evaluation in small metal fabrication facilities

Tools for systematic evaluation of machine-related hazards are lacking for the metal fabrication industry, which has one of the highest rates of non-fatal injury in the U.S. Here we describe the development and pilot evaluation of machine safety scorecards for an intervention study in small metal fabrication businesses. We developed 23 machine safety scorecards with items for point of operation guarding, guarding of moving parts, labelling of safe work practices, operation of emergency controls, lockout/tagout disconnects, and environmental conditions. Three trained raters used the scorecards to assess 179 machines in four pilot businesses ranging in size from 18 to 97 employees. At least five machines in eight categories were evaluated by all three raters (total of 59 machines). The mean score in the four shops for all machines ranged from 69.4-74.5 on a 100-pt scale. The score for individual machine types ranged from 34-72. Hydraulic power presses received the highest scores (71-72) while full-revolution mechanical presses (hands in die) had the lowest scores (34-45). The kappa statistic for all items ranged from 0.4-0.75, demonstrating fair to good inter-rater reliability. Medium priority items were generally scored with the highest reliability (kappa>0.8). Full-revolution presses (hands in die) were the most difficult to assess (kappa ranged from 0.5 to 0.63). Scorecards can be used to reliably and consistently assess safety for a range of metal fabrication machines. Our pilot study results emphasize that training is important to the reliable application of these scorecards.