Studies have shown that ventilation systems in buildings are largely responsible for the Sick Building Syndrome (SBS). The importance of good indoor air quality has become more apparent in countries which have great reliance on manpower resources as they strive for a knowledge-based economy in the 21st century [5]. To date, most people spend 90% of their time indoors, often in shared spaces. By offering mechanical environmental control over the indoor envir- onment, the occupants will be able to raise their expectations for a thermally comfortable indoor climate. Individual thermal comfort within a building enclosure is limited to a narrow range [6,7]. Despite the existence of extensive environmental control systems in buildings, grievances about the indoor climate are still commonplace [8,9].