Investigation of optimal table height and surface angle in meatcutting

Butchers have a high frequency of occupational disorders or pain localised to their hands, shoulders, low back and neck, compared with other occupational groups. It is likely that the disorders are caused by high loadings of these parts of the body during work. The high loadings have been found to be caused by high resistance when cutting, inappropriate working postures and by manual handling of material. To improve the butchers' working conditions by providing means for appropriate working postures, cutting tables with adjustable height and surface angle were constructed and tested. Evaluations were made during work in the laboratory and in the industry. The aim of these tests was to find the optimal height of the table for each butcher and to find out if a tilted surface would improve the working postures and be accepted by the butchers. The evaluations were made by biomechanical calculations from photos, ergonomic analysis of videotapes taken during the tests and by using ranking scales. The results show that (1) one optimal height of the table was not to be found, meaning a height resulting in a posture that causes no load on both back and shoulders at the same time; (2) a table height of 17 to 22 cm below elbow height resulted in low loadings on both the low back and the shoulders and was ranked as the most comfortable height; (3) tilting of the surface 5 degrees to 10 degrees was accepted by the butchers and ergonomically favourable; (4) the possibility of altering the table height during the workday was perceived as unloading since the load could be shifted between different parts of the body.