Assessment of indoor air quality in office buildings across Europe -The OFFICAIR study

摘要

The European project OFFICAIR aimed to broaden the existing knowledge regarding indoor air quality (IAQ) in modern office buildings, i.e., recently built or refurbished buildings. Thirty-seven office buildings participated in the summer campaign (2012), and thirty-five participated in the winter campaign (2012-2013). Four rooms were investigated per building. The target pollutants were twelve volatile organic compounds, seven aldehydes, ozone, nitrogen dioxide and particulate matter with aerodynamic diameter ＜2.5 μm (PM_(2.5)). Compared to other studies in office buildings, the benzene, toluene, ethylbenzene, and xylene concentrations were lower in OFFICAIR buildings, while the α-pinene and D-limonene concentrations were higher, and the aldehyde, nitrogen dioxide and PM_(2.5) concentrations were of the same order of magnitude. When comparing summer and winter, significantly higher concentrations were measured in summer for formaldehyde and ozone, and in winter for benzene, α-pinene, D-limonene, and nitrogen dioxide. The terpene and 2-ethylhexanol concentrations showed heterogeneity within buildings regardless of the season. Considering the average of the summer and winter concentrations, the acetaldehyde and hexanal concentrations tended to increase by 4-5% on average with every floor level increase, and the nitrogen dioxide concentration tended to decrease by 3% on average with every floor level increase. A preliminary evaluation of IAQ in terms of potential irritative and respiratory health effects was performed. The 5-day median and maximum indoor air concentrations of formaldehyde and ozone did not exceed their respective WHO air quality guidelines, and those of acrolein, α-pinene, and D-limonene were lower than their estimated thresholds for irritative and respiratory effects. PM_(2.5) indoor concentrations were higher than the 24-h and annual WHO ambient air quality guidelines.