Ergonomic risk factors for the wrists of hairdressers
This study utilized a portable data logger to measure the wrist angles and forearm flexor and extensor electromyography (EMG) of 21 hairstylists. The hairstylists were divided into two groups, one with 11 barbers (9 males and 2 females) specializing in men's hairdressing, and one with 10 hairdressers (2 males and 8 females) specializing in women's hairdressing. The standard haircut task was divided into three subtasks: hair cutting, washing and blow-drying. The mechanical exposures of the overall task and subtasks were quantified to compare how subtasks, occupational groups, and gender groups differ. Experimental results show that the average time to finish a woman's haircut (51.4min) is significantly longer than that for a man's haircut (35.6min) (p<0.005). Female hairstylists had significantly greater EMG activity than male hairstylists did (p<0.001). The non-dominant hands of hairdressers have significantly higher overall wrist velocity than those of barbers (p<0.005). Analytical results suggest that the relatively higher force exertion and wrist velocity of female hairstylists combined with prolonged exposure may account for the higher rate of hand/wrist pain in female hairdressers than in male barbers.
ergonomic risk factors workload musculoskeletal disorder