A new indoor environmental quality equation for air-conditioned buildings

Sustaining indoor environmental quality (IEQ) in high rise centrally air-conditioned buildings remains a difficult task of building managers because of the lack of a suitable instrument to measure the physical parameters of IEQ and to record the simultaneous occupant subjective responses. An IEQ logger is developed to facilitate the continuous monitoring of the state of IEQ. The performance of this logger has been validated by large-scale surveys in air-conditioned buildings in Hong Kong using the appropriate international standards and protocols. The compactness of the logger made it versatile for use in the study of total IEQ. It renders the development of a total IEQ comfort model possible. This composite IEQ index attempts to integrate the total responses of the four fundamental indoor environmental qualifiers, namely, thermal, air quality, visual and aural comfort. The IEQ index expresses the dissatisfaction as can be predicted by measurements of the essential parameters. The concept of an IEQ index opens up a new approach to the design for acceptable indoor IEQ. The IEQ logger facilitates building managers in sustaining their targeted IEQ levels.