Ergonomic Risk Assessment of Rubber Tappers Using Ovako Working Posture Analysing System (OWAS)

Abstract

Natural rubber is a vital raw material for modern-day industries. It is commercially produced by extracting the latex of certain tree species that contain significant amounts of rubber and the process is called rubber tapping. In performing this operation, workers have to assume awkward postures, including extending of arms, side bending, twisting, flexion and/or extension of the neck, trunk, and wrists. Typically, workers tap at least 300 trees in a day, consequently subjecting them to these hazardous postures repeatedly. Such a cyclic and monotonous work activity involving numerous ergonomic risk factors exposes rubber tappers to great risks of musculoskeletal disorders (MSDs). This study was conducted among thirty rubber tappers in Kerala, India, to assess their working postures and evaluate their susceptibility to MSDs. Participants were directly observed while they were working, and their work activity was also videotaped with prior consent. The OWAS was used for carrying out a video-based posture analysis of rubber tappers to study the effects of their postures on the musculoskeletal system and the need for remedial measures. It was found that 30% of the participants had postures that would slightly affect their body, whereas 26% of participants had postures that had to be corrected soon in line with higher action categories.