Method for identifying particle sources

Physical IAQ parameters were sampled and results plotted in an IAQ study of a high-rise building in Hong Kong. Chemical samples were obtained and results indicated acceptable IAQ based on local and international guidelines. Common complaints of poor IAQ because of "stuffy air" and "odors" from unidentified sources have been recorded ever since initial occupancy. Source of odor was traced , it came from a poorly designed AHU drain-traps. A follow-up survey was performed. Results are compared and reported.