Abstract—The objective of this study is to determine the thermal comfort among worker at Malaysian automotive industry. One critical manual assembly workstation had been chosen as a subject for the study. The human subjects for the study constitute operators at Body Assembly Station of the factory. The environment examined was the Relative Humidity (%), Airflow (m/s), Air Temperature ( o C) and Radiant Temperature ( o C) of the surrounding workstation area. The environmental factors were measured using Babuc apparatus, which is capable to measure simultaneously those mentioned environmental factors. The time series data of fluctuating level of factors were plotted to identify the significant changes of factors. Then thermal comfort of the workers were assessed by using ISO Standard 7730 Thermal sensation scale by using Predicted Mean Vote (PMV). Further Predicted percentage dissatisfied (PPD) is used to estimate the thermal comfort satisfaction of the occupant. Finally the PPD versus PMV were plotted to present the thermal comfort scenario of workers involved in related workstation. The result of PMV at the related industry is between 1.8 and 2.3, where PPD at that building is between 60% to 84%. The survey result indicated that the temperature more influenced comfort to the occupants. Keywords—Thermal, Comfort, Temperature, PPD, PMV. I. INTRODUCTION HE ventilation of building is used to maintain indoor air quality and thermal comfort. In order to attain these objectives, airflow rate should be controlled. The minimal airflow rate is determined by indoor air quality requirements so that the maximal concentration for every pollutant is lower than the maximum admitted. Thermal A. R. Ismail is with the Department of Mechanical & Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia (phone: +60389216775; fax:+ 60389259659; e-mail: arasdan@eng.ukm.my). N. Jusoh is with the Department of Mechanical & Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia (e-mail: pajiwakeup@yahoo.com). M. Z. Nuawi with the Department of Mechanical & Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia (e-mail: zaki@eng.ukm.my). B. M. Deros is with the Department of Mechanical & Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia (e-mail: hjbaba@eng.ukm.my). N. K Makhtar is with the Technical School of Sepang, Lot 1909, Mukim Dengkil, 43800 Sepang,Selangor, Malaysia (e-mail: nkamilahm@gmail.com) M. N. A. Rahman is with the Department of Mechanical & Materials Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia (e-mail: mnizam@eng.ukm.my). comfort is influenced by air parameters (temperature, humidity, velocity and turbulence) and surface temperatures (walls, windows) but also by the type of human activity and clothing. Thermal comfort has a great influence on the productivity and satisfaction of indoor building occupants [15]. Thermal comfort is very difficult to define. This is because we need to take into account a range of environmental and personal factors when deciding on the temperatures and ventilation that will make feel comfortable. The best that we can realistically hope to achieve is a thermal environment which satisfies the majority of people in the workplace, or put more simply, ‘reasonable comfort’ [9]. Thermal comfort can be defined as that condition of mind which expresses satisfaction with the thermal environment [15]. The reference to ‘mind’ indicates that it is essentially a subjective term; however, there has been extensive research in this area and a number of indices exist which can be used to assess environments for thermal comfort [7]. Fanger (1970) suggested three conditions for comfort; these are that the body is in heat balance and that the mean skin temperature and sweat rate are within limits required for comfort. Conditions required for heat balance can be derived from a heat balance equation. Mean skin temperatures and sweat rates that are acceptable for comfort have been derived from empirical investigation [11]. Predicted mean vote (PMV) is a parameter for assessing thermal comfort in an occupied zone based on the conditions of metabolic rate, clothing, air speed besides temperature and humidity. PMV values refer the ASHRAE thermal sensation scale [3] that ranges from –3 to 3 as follows: 3=hot, 2=warm, 1=slightly warm, 0=neutral, –1=slightly cool, –2=cool, – 3=cold. Fig. 1 summarizes the overall process of using the six variables associated with thermal comfort sensation to evaluate the PMV [1]. The general comfort equation developed by Fanger [11] to describe the conditions under which a large group of people will feel in thermal neutrality is too complex and cannot be used in real time applications. A. R. Ismail, N. Jusoh, M. Z. Nuawi, B. M. Deros, N. K. Makhtar, and M. N. A. Rahman Assessment of Thermal Comfort at Manual Car Body Assembly Workstation T World Academy of Science, Engineering and Technology International Journal of Mechanical and Mechatronics Engineering Vol:3, No:6, 2009 690 International Scholarly and Scientific Research & Innovation 3(6) 2009 ISNI:0000000091950263 Open Science Index, Mechanical and Mechatronics Engineering Vol:3, No:6, 2009 publications.waset.org/11154/pdf