Indoor Air Quality in Selected Samples of Primary Schools in Kuala Terengganu, Malaysia Marzuki Ismail a , Nur Zafirah Mohd Sofian a and Ahmad Makmon Abdullah b a Department of Engineering Science, Faculty of Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Malaysia b Department of Environmental Science, Faculty of Environmental Studies, Universiti Putra Malaysia, 43300 Serdang, Selangor, Malaysia Abstract Studies have found out that indoor air quality affects human especially children and the elderly more compared to ambient atmospheric air. This study aims to investigate indoor air pollutants concentration in selected vernacular schools with different surrounding human activities in Kuala Terengganu, the administrative and commercial center of Terengganu state. Failure to identify and establish indoor air pollution status can increase the chance of long-term and short-term health problems for these young students and staff; reduction in productivity of teachers; and degrade the youngsters learning environment and comfort. Indoor air quality (IAQ) parameters in three primary schools were conducted during the monsoon season of November 2008 for the purposes of assessing ventilation rates, levels of particulate matter (PM 10 ) and air quality differences between schools. In each classroom, carbon monoxide (CO), CO 2 , air velocity, relative humidity and temperature were performed during school hours, and a complete walkthrough survey was completed. Results show a statistically significant difference for the five IAQ parameters between the three schools at the 95.0% confidence level. We conclude our findings by confirming the important influence of surrounding human activities on indoor concentrations of pollutants in selected vernacular schools in Kuala Terengganu. Keywords: Indoor air quality (IAQ); Particulate matter (PM 10 ); Carbon monoxide (CO); Carbon dioxide (CO 2 ); Terengganu 1. Introduction Indoor air pollution has been identified as one of the most critical global environmental problems (WRI, 1998). In the last several years, Indoor Air Quality (IAQ) in workplace and residential environments caught the attention of scientists and the public redun- dant. Until the late 1960s, attention to air quality was primarily focused on the outdoors because, by that time, outdoor air pollution was considered responsible for many adverse health effects (Zhang, 2005). People spend most of their time indoors and institutional buildings, such as schools, represent a significant fraction of the day (Yip et al., 2004); and since people spend more than 90% of their time indoors, good indoor air quality is very important to us. Air quality at classrooms is of special concern since children are susceptible to poor air quality, and indoor air problems can be subtle and do not always produce easily recognizable impacts on health and wellbeing (USEPA, 1996). The physical environment of children is different and more vulnerable from those of adults, even when living in the same home. Failure to prevent indoor air pollution can increase the chance of long-term and short-term health problems for students and staff; reduction in productivity of teachers; and degrade the student learning environment and comfort. Particulate air pollution has been found associated with increased respiratory symptoms, school absences and medication use for asthmatic children (Peters et al., 1997). Moreover, the Canadian Lung Association (CLA) 2002 estimates up to 10% of children experience symptoms of asthma, a condition accounting for 1 /4 of school absenteeism. The metabolic rate per kilogram of body weight of children is much higher than that of an adult, in part because children are still developing and they are smaller. This means that their respiratory rate, for example, is proportionately greater and they breathe in much more air pollution in relation to their body weight than an adult in similar circumstances (Yassi et al., 2001). Also, their bodies are still developing and the effect of an environmental insult can interfere with that development. Children and elderly are known as sensitive group to indoor air pollution. Previous studies have found out that indoor air quality affected these sensitive groups more compared to ambient atmospheric air. Due to this fact, an indoor air quality study was carried out in selected vernacular schools in Terengganu state, Malaysia. This study is imperative because children spend half of their day in school buildings. Moreover, Available online at www.tshe.org/EA EnvironmentAsia 3(special issue) (2010) 103-108 The international journal published by the Thai Society of Higher Education Institutes on Environment Environment Asia