Design and Development of an Ergonomic Kharak by using student's anthropometric characteristics of Isfahan University of Art

Back and shoulder pain are most common musculoskeletal disorders in students, That the way of sitting or interactions with academic equipment is a major risk factor for these disorders. The aims of this study is redesign and construct a prototype of painting chair (Kharak) by using industrial design and ergonomic methods to reduce musculoskeletal disorders and increase user satisfactions. This is an experimental study to redesign Kharak by industrial design tools, anthropometry analysis and rapid upper limb assessment (RULA) methods. Participants were 28 students of Isfahan University of Art that using current Kharak for painting or drawing in their college. 14 % of participants have RULA grand score 7, 39 % have grand score 5-6 and 47% with the RULA grand score 3-2. Main factors affecting the RULA grand score were sex (P=0.003), stature (P=0.0004) and popliteal height (P=0.004). Also mean of women’s RULA grand score was higher than men. According to anthropometry analysis seat height of redesigned Kharak 430 mm was determined and proper backrest with 105° for semi recline was added to final design.