ERGONOMIC RISK AND PHYSICAL WORKLOAD ASSESSMENT IN SMALL-SCALE TOFU INDUSTRY: A CASE STUDY AT GANG KEDELAI RAYA TOFU PRODUCTION CENTER

Ade Sri mariawati; Lovely   Lady; Lely  Herlina; Muhamad  Hisyam

doi:10.24961/j.tek.ind.pert.2026.36.2.159

Authors

Ade Sri mariawati Department of Industrial Engineering, Universitas Sultan Ageng Tirtayasa,
Lovely Lady Department of Industrial Engineering, Universitas Sultan Ageng Tirtayasa,
Lely Herlina Department of Industrial Engineering, Universitas Sultan Ageng Tirtayasa, Indonesia
Muhamad Hisyam Department of Industrial Engineering, Universitas Sultan Ageng Tirtayasa,

DOI:

https://doi.org/10.24961/j.tek.ind.pert.2026.36.2.159

Abstract

Many small-scale tofu industries still depend on manual production systems, which often require workers to perform repetitive movements, lift heavy loads, and maintain awkward postures for long periods. These conditions may increase the risk of musculoskeletal disorders and physical fatigue. This study aimed to assess musculoskeletal complaints, work posture risks, and physical workload among workers in small-scale tofu industries, and to develop an ergonomic improvement proposal for the existing production system. The study was conducted in five small-scale tofu industries in Cilegon City involving 13 workers engaged in main production activities, including soybean washing, grinding, boiling, filtering, pressing, cutting, and packaging. Musculoskeletal complaints were identified using the Nordic Body Map (NBM), posture risks were evaluated using the Rapid Upper Limb Assessment (RULA), and physical workload was measured based on Cardiovascular Load (%CVL). The NBM results indicated that workers commonly reported discomfort in the lower back, shoulders, arms, wrists, and legs. Several production activities showed high RULA scores of 6–7, particularly tasks involving bending, reaching, lifting, and repetitive upper-limb movements, indicating that corrective action was urgently needed. The mean %CVL was 37.15%, which falls into the moderate workload category. Based on these findings, a multi-level production floor was proposed as an ergonomic improvement to reduce excessive bending, manual lifting, and non-neutral working postures. The proposed design has not yet been implemented in the workplace; however, it was evaluated through posture reassessment, showing a potential reduction in RULA scores to 2–3 for all main activities. These results suggest that ergonomic redesign can improve worker safety and comfort while supporting more sustainable small-scale tofu industries.

Keywords:
Ergonomic, Small-scale tofu industry, Nordic Body Map .