Effective sampling protocol for managing indoor air quality in air-conditioned buildings

The Environmental Protection Department conducted a territory-wide indoor air qualitysurvey in Hong Kong. The report released in 1997 confirmed that one-third of the sampledbuildings were classified as sick buildings. Many of the causes could be attributed tounacceptable indoor air quality (IAQ). In response to this, the Indoor Air Quality ManagementGroup distributed a Guidance Notes for the Management of Indoor Air Quality in Offices andPublic Places for public consultation. It includes an annual IAQ certification scheme. Thescheme is required to sample air at each location for nine IAQ parameters and three thermalcomfort parameters. The cost of IAQ sampling per point is estimated averaged at US$500.This requirement adds to the annual budget of a building at around US$15 000. If allair-conditioned buildings are IAQ certified, the total annual budget can be as high as US$75million. Although this requirement is voluntary, building managers are concerned that it maybe regulated. This paper describes a review of IAQ sampling in buildings and thedevelopment of a protocol of effective sampling based on statistical sampling principles. Toease the tension of the building industry, this sampling protocol can reduce the samplingrequirement by as much as 50% with an equivalent representation.