Assessment of risk factors of upper limb musculoskeletal disorders in a meat processing plant

The aim of this study was to evaluate the risks associated with repetitive movements of the upper limbs in different meat processing tasks of a pig slaughterhouse, using the OCRA Checklist. The study was conducted in a Brazilian pig slaughterhouse with 1,000 workers, divided into two work shifts. To evaluate the risks associated with repetitive movements of the upper limbs, 10% of the workforce was assessed while carrying out their work tasks, using the checklist proposed by the OCRA method. Descriptive statistics and the Student t-test (SPSS 17.0) were applied to compare the risks between both sides of the workers’ bodies (p≤0.05). There were 39 work activities analyzed from the productive sectors. The average of occupational repetitive actions performed by workers was 54.5±20.8 per minute, representing 7 points on the OCRA scale (0 to 10 points). The average score of the OCRA Checklist was 18.8±6.0 (medium risk). The scores for the right upper limb (18.6 - medium risk) differed statistically (p=0.016) from the left upper limb (13.8 - medium risk). Five work tasks were considered high risk, 29 were classified as medium risk, one as low risk, one as very low risk and three as acceptable risk. Performing simulations in 32 of the 35 activities made it possible to reduce the UL-WMSD risk to very low levels, by only decreasing the work pace. In three of the activities, a very low risk level could not be achieved by only reducing the work pace, due to the high demand for strength required to perform these tasks. These results suggest that most pig processing tasks, classified as high (13%) and medium risk (74%), predispose workers to a greater probability of developing upper limb work-related musculoskeletal disorders (>21.5% probability for high risk and 10.8 to 21.5% for medium risk). Simulations of decreasing the work pace showed the effectiveness of this organizational measure to reduce the risk of UL-WMSDs.