Occupational risks factors identified and interventions suggested by welders and computer numeric control workers to control low back disorders in two steel companies

Abstract

Work-related low back disorders (WLBD) are common and expensive. This study assessed perceived workload and identified issues and possible improvements to reduce WLBD in 64 welders and 44 computer numeric control workers (CNC workers). Injury records were reviewed and a questionnaire was completed. Discomfort ratings and visual analogue scales were compared using one-way ANOVA with Fisher's least-significant difference post hoc test. The annual incidence of recorded WLBD was lower for welders (3.4%) than for CNC workers (5.4%). On the other hand, the working-life incidences of reported WLBD and the point prevalences of low back pain were higher for the welders (55% and 27%, respectively) than for the CNC workers (36% and 16%). The discomfort scores for the low back region were higher than the scores for the other body parts. The weight manually handled [mean (S.D.)] by the welders [21 (6) kg] was lower than by the CNC workers [35 (11) kg]. Perceived exertion was strong for both groups [5 (1)]. For the welders, the postures, repetitions, and duration contributed more to the total effort than the movements and forces ( p<0.035). For CNC workers, repetitions and duration contributed more to the total effort than postures, movements, and force ( p<0.044). The workers identified relevant problems and possible improvements for their jobs. Recommended improvements included adjustable tables, stretching, and crane use by welders, and training, standing mats, clear limits, stable magnets, and less asymmetrical lifting by CNC workers. Précis This study evaluated reported occupational risk factors for WLBD among welders and CNC workers from two steel companies. A questionnaire was responded by 108 steel workers. The information presented can be used to design participatory ergonomic interventions aimed at reducing WLBD.