Human Factors Engineering for the Design of Tools and Equipment for Community Enterprises of Curry Paste Production

Abstract

This study aimed to apply human factors engineering principles to the design of tools and equipment for the Dusongpayae Community Curry Paste Enterprise, located in To Lang Subdistrict, Yaring District, Pattani Province. Initial health surveys and ergonomic risk assessments using RULA and REBA revealed that workers were at a high risk level (RULA = 7, REBA = 9), indicating that current working conditions are problematic and require immediate workstation improvements. Anthropometric measurements were conducted on 15 female participants, selected through purposive sampling, to support the design. For the lemongrass cutting machine, the 5th and 95th percentile elbow height (92.00–98.30 cm) was considered, and the working height was set at 90 cm to be below elbow level for greater comfort. For the chair design, the seat height was based on the 5th and 95th percentile of popliteal height (36–42 cm), adjustable within 35–45 cm. Seat depth was determined using the 5th percentile of buttock-popliteal length (38 cm), while seat width was based on the 95th percentile of hip breadth while sitting (38.30 cm), set at 40 cm. The working reach distance was designed according to the 5th and 95th percentile forward arm reach (69–73 cm), ensuring suitability as users can freely adjust the positioning of the cutter and chair. Testing the redesigned tools with the original participants demonstrated a clear increase in productivity, as the time required to slice 15 kilograms of lemongrass was reduced by 9.08 minutes. Furthermore, ergonomic risks significantly decreased to safer levels (RULA = 4, REBA = 4), and overall user satisfaction was rated at a high level (mean = 4.38). These findings demonstrate that applying human factors engineering in tool and equipment design effectively enhances productivity and reduces ergonomic risks for the community curry paste enterprise.