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Low productivity and high sick leave in the weaving division of PT XYZ in Yogyakarta are caused by excessive physical and mental workload on Shuttle Loom Unit 2 operators. The productivity of the weaving division of PT XYZ was recorded at only 61.96% (target 75%) with sick leave of 4.17%, indicating operator fatigue. This study measured physical workload using the Cardiovascular Load (CVL) method based on heart rate and mental workload using NASA-TLX, and analyzed the correlation with age and length of service. The results showed a moderate physical workload category (40% light CVL <30, 60% moderate 30-60) at a temperature of 30.5°C, and high-very high mental workload (45% high 50-79, 55% very high ≥80, average EF 79.3) due to strict quality targets (0.5% defects). There is a correlation between CVL and NASA-TLX with age. Recommendations include reducing the daily production target from 100 to 85-88 yards, optimizing ergonomics, and training to reduce EF to 65 and defects to 0.3, to increase effective productivity.

MMP is a metal manufacturing company engaged in casting, forging, and machining processes with a three-shift work system, including night shifts that may increase mental and physical workload due to disruptions in workers’ biological rhythms. This study aims to analyze the mental and physical workload of die casting machine operators during the night shift and to propose improvement measures using the Fault Tree Analysis (FTA) method. The study involved 23 operators, with mental workload assessed using NASA-TLX and physical workload measured using CVL. The results indicate that mental workload falls into high to very high categories, with WWL values ranging from 46.6 to 97.3, where 12 operators experienced very high mental workload. The dominant contributing dimensions were effort, physical demand, and temporal demand. Meanwhile, physical workload ranged from 19.48% to 36.36% CVL, with most operators not experiencing fatigue. Although physical workload remains within acceptable limits, the high mental workload indicates the need for improvements. FTA analysis identified key contributing factors, including work methods, work systems, ergonomics, machine conditions, and the work environment. Proposed improvements include job rotation, improvements in work methods and task distribution, adjustments to the work system, enhanced machine maintenance, and ergonomics-based workplace improvements.

Lifting activities are an essential part of manual material handling across various industrial sectors and constitute a primary source of ergonomic risk exposure when performed with inappropriate work postures. The use of hands-off tools such as push-pull sticks is often implemented to maintain a safe distance between workers and loads and to reduce exposure to line-of-fire hazards. However, the implementation of work aids does not automatically ensure neutral work postures, as push-pull techniques, reach distances, and environmental conditions can still lead to awkward postures. This study aims to evaluate the work posture risk in lifting activities using a fiber-composite push-pull stick based on the Rapid Entire Body Assessment (REBA) method. The research was conducted as an observational analytic field study involving nine workers in tubular pushing and pulling activities. Work postures were documented through direct observation and visual recordings, then assessed using REBA to obtain risk scores, risk categories, and required corrective actions. The results indicate that work postures fall into the medium to high-risk categories, with trunk and shoulder components being the dominant contributors. These findings confirm the need for improvements in work methods, ergonomic training, and strengthening of lifting SOPs to optimize the safety and ergonomic benefits of work aids.

Low back pain (LBP) is one of the most common musculoskeletal complaints globally and is the main cause of decreased work productivity. One of the risk factors that has been widely studied in the literature is prolonged sitting duration. Prolonged sitting activities cause increased static pressure on the lumbar spine, fatigue of the supporting muscles, as well as a decrease in local blood flow that can trigger chronic pain. This study is a literature review with a meta-analytical approach that aims to analyze the relationship between long-term sitting and the incidence of LBP. The review process was carried out following PRISMA guidelines through searches on PubMed, Scopus, ScienceDirect, and Google Scholar databases for publication in 2020–2025. Of the 20 previous studies analyzed, most showed a positive association between sitting time and an increased risk of LBP, both in adults, adolescents, and children. Sitting for more than 6 hours per day increases the risk of LBP by 33%, especially in individuals with low physical activity. In addition, longer sitting durations with poor posture and minimal active rest were found in the group of office workers and professional drivers who had a high prevalence of LBP. Physical activity has been shown to play a protective role against the risk of LBP, while ergonomic interventions such as lumbar support can reduce pain complaints. Although most studies were observational, the consistency of results supports the importance of prevention through reduced sitting time, increased physical activity, and ergonomic work environment settings. These findings provide a scientific basis for multidimensional interventions to effectively reduce the incidence of LBP.  

Musculoskeletal Disorders (MSDs) complaints in muscles, joints, and soft tissues can be caused by poor posture, repetitive movements, and excessive physical load. In the wet cake-making industry, workers often sit or stand for long periods, bend, and perform monotonous hand movements, which increases the risk of MSDs. The impact includes decreased work comfort, productivity, and quality of life. This study aims to assess the ergonomic risk level in wet cake-making workers and identify the relationship between work activities and MSD complaints. The method used is descriptive quantitative research with a cross-sectional design, involving 45 workers at Kue X Silaberanti. Ergonomic risk was assessed using the REBA method, while MSD complaints were measured using the Nordic Body Map questionnaire. The results show that in the mixing process, 58.8% of workers experienced a very high risk of MSDs. In the molding and baking processes, 52.9% and 68.8% of workers, respectively, were at high risk. The most frequent complaints were pain in the back, neck, shoulders, arms, and wrists due to poor posture and repetitive movements. To reduce the risk of MSDs, workers need to improve their posture, use ergonomic aids, rotate tasks, and undergo training in safe working techniques.