Development and evaluation of new prototype seat for commercial stage bus drivers

• Main Author: Wan Hassan, Wan Chik Zaharah
• Format: Thesis
• Language: English
• Published: 2009
• Online Access: http://psasir.upm.edu.my/id/eprint/49932/1/FPSK%28m%29%202009%2013RR.pdf; http://psasir.upm.edu.my/id/eprint/49932/

As a development country, Malaysia has experiencing rapid development in public transport due to the process of urbanization, economic development and population growth. This rapid increase in the total number of vehicles on roads created traffic congestion. Previous study has reported that bus drivers were highly exposed to ergonomic hazards due to poor seat design. Prolong exposure resulted in the incidence of having low back pain. Thus, a cross sectional study was carried out among Malaysian male bus drivers from July 2004 to January 2006 with the main objective of developing a new bus drivers’ seat design based on anthropometric measurements of Malaysian males. A total of 669 respondents were selected using a stratified random sampling from central, eastern and southern regions of Peninsular Malaysia. Modified Nordic questionnaires were used to determine demographic information, prevalence of low back pain and risk factors associated with low back pain (LBP) among the bus drivers. Martyn Type Anthropolometer was used to measure anthropometrics parameters namely sitting eye height, sitting shoulder height, elbow rest height, popliteal height with shoes, popliteal height without shoes, knee height with shoes, knee height without shoes, elbow breadth, hip breadth, hip breadth, buttock to popliteal length, buttock to knee length and lumbar support height. Measurements for current bus seat taken were backrest height, backrest width, seat pan dept, seat pan width and seat height. Rapid upper Limb Assessment (RULA) score of the proposed seat design. The result showed a high prevalence of life time low back pain (59.5%) among Malaysian male bus drivers in Peninsular Malaysia. Logistic regression analysis showed that low back pain was significantly associated (p>0.05) with exposure to vibration (2.285, 95% CI 1.610-3.243), prolonged sitting (2.729, 95% CI 1.525 – 4.886), hard cushion (2.586, 95% CI 1.396 – 4.788), uncomfortable seat (2.256, 95% CI 1.346 – 3.782), bending (3.928, 95% CI 0.854 – 6.076) and lifting load while working (1.087, 95% CI 0.603 – 1.959). Anthropometric measurements obtained from this study were used a guide in designing a new seat. The current seat measurements were significantly different (p<0.05). RULA simulation showed that the new proposed seat had an acceptable score of 2 while for the current seat score 3. The current seat contributed to the LBP and newly improved seat can be designed and developed using the anthropometric as well the RULA analysis method.