Indoor/outdoor air quality correlation and questionnaire survey at two staff quarters in Hong Kong

The indoor and outdoor air quality at two staff quarters of the Hong Kong Polytechnic University (HKPU) were investigated during January and February 1996. The air pollutants measured were NOx, NO, NO2, SO2, CO, and O-3. All indoor and outdoor pollutant concentrations did not exceed the American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) and the National Ambient Air Quality Standard (NAAQS) standards. Significant differences in the pollutant concentrations were observed for samples collected on weekdays when compared with those collected on Sundays (P-value < 0.05). The average indoor and outdoor pollutant levels at the Tsim Sha Tsui East (TSTE) quarter were higher than those at the Shatin (ST) quarter except for O-3. All O-3 levels were found to be lower at the TSTE quarter than at the ST quarter, and TSTE/ST O-3 concentration ratios were 0.72 for the outdoors and 0.79 for the indoors, respectively. Lower O-3 levels at the TSTE quarter were due to the NO titration reaction. All indoor pollutant levels were lower than those at the outdoors except for CO, which indicates the presence of indoor CO sources. A questionnaire survey was used to study the relationship between prevalence of illnesses and risk factors. (C) 1998 Elsevier Science Ltd.