Risk factors of musculoskeletal disorders in loading and unloading tasks of couriers

BACKGROUND: The use of home delivery services has expanded due to coronavirus disease - 2019, and couriers' high level of work intensity has become a severe social issue in various nations. OBJECTIVE: This study investigates the risk factors of musculoskeletal disorders (MSDs) caused by frequent loading and unloading actions, known to be the most demanding tasks for couriers. METHODS: A self-report survey and post-hoc interview were employed to collect personal information, task frequency, and the incidence of MSDs. Frequent actions during loading and unloading packages were identified, and the Rapid Entry Body Assessment (REBA) and National Institute for Occupational Safety and Health (NIOSH) lifting equations were assessed. RESULTS: Approximately 29.5% of the 44 subjects suffered from MSDs, and identify the types of actions that frequently occur during loading and unloading packages. According to the REBA survey, 60% of the responses for both loading and unloading are distributed within the risk range of 8-13 points, suggesting a high risk (mean REBA score: 8.8 (loading), 8.5 (unloading)). In every case, NIOSH determined that the lifting index (LI) was harmful (mean LI: 1.62). Thereby, the bending or twisting posture of the hands and neck, long horizontal distance between the packages and the body, and high lifting frequency were identified as major problems. CONCLUSION: The study identified a very high level of musculoskeletal risk for couriers, and the detailed working methods and body parts vulnerable to MSDs.