Prevalence of musculoskeletal disorders and ergonomic assessments of cleaners

Abstract
Background Professional cleaning has emerged as a new industry in Taiwan in the past few years. However, information about the workload and prevalence of musculoskeletal disorders (MSDs) among these workers is still limited. This study investigated the prevalence of musculoskeletal discomforts and the characteristics of musculoskeletal activities of cleaning workers in Taiwan. Methods Face-to-face interviews to collect basic information and to administer the Chinese version of the Standardized Nordic Musculoskeletal Questionnaire were conducted on 180 cleaners. Biaxial electrogoniometers and electromyography were used to characterize the motion and forceful exertion of 56 cleaners during work. Results Nearly 90% of the participants reported musculoskeletal discomfort in at least one body part due to work. Of the nine body parts examined, hand/wrist (41.7%), shoulder (41.1%), low back (37.8%), and elbow (33.3%) were most frequently reported to exhibit discomfort. Additionally, time pressure as a psychosocial risk factor was found to be associated with discomfort in several body parts. Measurements of electrogoniometry showed that wrists of many cleaners were frequently held in extreme angles of ulnar/radial deviation, leading to an increased risk of developing carpal tunnel syndrome. Motion repetitiveness and force output during mopping and sweeping tasks were considered less influential in developing hand/wrist discomfort. Conclusions Cleaners in Taiwan are a high-risk group for developing MSDs, and solutions are needed to avoid extreme motion angles of the wrists when performing cleaning tasks. Moreover, both psychosocial stress and the welfare of this group of workers deserve immediate attention from management and the government. Am. J. Ind. Med. 55:593–604, 2012.