INDOOR AIR QUALITY IN COMMERCIAL BUILDINGS IN SINGAPORE - A CASE STUDY APPROACH

Abstract

This dissertation provides a "mapwork" of the indoor air quality (IAQ) of a large commercial building in the Central Business District, through 3 case studies, using objective and subjective evaluations. Objective evaluation involved the measurement of chemical, physical and biological pollutants and ventilation parameters, with subjective study being carried out through a self-administered questionnaire survey. The causes of sick building syndrome (SBS) and the various factors affecting indoor air quality are discussed. The indoor pollutants contributing to SBS are also examined in detail. The frequency of experience of SBS symptoms was found to be generally high throughout the areas being studied. Despite the high symptom rates, majority of the occupants did not rate the indoor air quality as bad. The feedback from the survey did not show consistent arguments and only related well with some of the objective parameters. Total Volatile Organic Compounds (TVOC) levels, biological and particulate counts were found to be high in the study areas. These elements which are probable causes of SBS could be clearly identified in one of the case studies. The results from the ventilation study do not relate well with the responses of the occupants. The air was found to be well-mixed and there was no short-circuiting on a global scale.