B080 Office IAQ benchmark

Benchmarking indoor air quality for ‘Grade A’ offices in Hong Kong

Brief:

In Hong Kong, indoor air quality (IAQ) labels for air-conditioned offices have been proposed by a ‘full’ IAQ assessment of the exposure levels of nine common indoor air pollutants and three thermal comfort parameters. For a simple and practical IAQ benchmarking system, this study proposed to use an IAQ index as a benchmarking parameter for ‘Grade A’ airconditioned offices of Hong Kong. The IAQ index was the average fractional dose to certain exposure limits of three representative indoor air pollutants regarding IAQ control measures of dilution, filtration and emission control, i.e. carbon dioxide (CO₂), respirable suspended particulates (RSP) and total volatile organic compounds (TVOC). A simple 5-star rating benchmarking system was proposed to classify the IAQ of offices. Offices with the bottom 10% IAQ index would be awarded the highest rating ‘5 stars’, ‘4 stars’ for the next 22.5%, ‘3 stars’ for the next 35%, ‘2 stars’ for the next 22.5% and ‘1 star’ for the top 10% respectively. Base on the proposed benchmarks, the IAQ of some benchmarked Grade A offices in Hong Kong was investigated. In particular, IAQ benchmarks at over 1300 Grade A offices were evaluated. The results were compared with the previous measured results made in Grade A offices in Hong Kong. These simple benchmarks would serve as good indication of IAQ for air-conditioned offices of Hong Kong and provide useful information for maintaining the IAQ of offices.

Further Information:

Hui PS, Mui KW, Wong LT, Leung CH, 2009. Benchmarking indoor air quality for ‘Grade A’ offices in Hong Kong, Joint Symposium 2009 on building sustainability under one sky, Tian Yu Hotel, 28-29 June, Tianjin, China, pp. 1-7.