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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 <2.5μm (PM). 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 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 indoor concentrations were higher than the 24-h and annual WHO ambient air quality guidelines.

The aim of this study was to characterize the relationship between Indoor Air Quality (IAQ) and ventilation in French classrooms. Various parameters were measured over one school week, including volatile organic compounds, aldehydes, particulate matter (PM2.5 mass concentration and number concentration), carbon dioxide (CO2 ), air temperature, and relative humidity in 51 classrooms at 17 schools. The ventilation was characterized by several indicators, such as the air exchange rate, ventilation rate (VR), and air stuffiness index (ICONE), that are linked to indoor CO2 concentration. The influences of the season (heating or non-heating), type of school (nursery or elementary), and ventilation on the IAQ were studied. Based on the minimum value of 4.2 l/s per person required by the French legislation for mechanically ventilated classrooms, 91% of the classrooms had insufficient ventilation. The VR was significantly higher in mechanically ventilated classrooms compared with naturally ventilated rooms. The correlations between IAQ and ventilation vary according to the location of the primary source of each pollutant (outdoor vs. indoor), and for an indoor source, whether it is associated with occupant activity or continuous emission.

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h i g h l i g h t sPassive sampling methodology for particulate matter in indoors is proposed. Autumn was the season that presented higher particle masses concentrations. Calcium is the major indoor PM component in rural and urban classrooms. Soil re-suspension, traffic and chalk are the main sources of indoor PM. Natural ventilation is a major contributor to the variability of indoor PM. a r t i c l e i n f o a b s t r a c tPassive sampling methodology was applied to collect particulate matter (PM) in classrooms of urban and rural primary schools. The samples were taken during a year by passive deposition allowing the study of seasonal variability of the particles masses and chemical content. Chemical characterization of the collected particles was performed in order to measure its soluble ions content and elemental composition. To identify the main polluting sources, correlations between parameters and enrichment factors were studied. Higher particle masses concentrations were registered in autumn, with a mean of 1.54 AE 0.74 mg day À1 cm À2 . The major element in the collected particles was calcium, representing 63e73% of the analyzed mass of the particles inside the urban classrooms. In the rural cluster, calcium remained the major component but with a slight lower contribution to the overall particles composition (42e46%). The calcium source was hypothesized to be the chalk used in the blackboards of the classrooms due to a strong correlation found between Ca 2þ and SO 4 2À . Soil re-suspension, traffic and other anthropogenic emission sources were also identified. Analysis showed enrichment of the particles with Br, Ca, Zn and Sb in the urban cluster and enrichment of the same elements, except for Ca, in the rural cluster. The comparison between the results from both clusters allowed the identification of classrooms with higher particles concentrations that can indicate potential indoor air quality problems (reflected by an indoor accumulation of pollutants).

Abstract:People spend most of their time in indoor environments and, consequently, these environments are more signifi cant for the contribution of the daily pollutant exposure than outdoors. In case of children, a great part of their time is spent at school. Therefore, evaluations of this microenvironment are important to assess their time-weighted exposure to air pollutants.The aim of this study was to assess the children exposure to bioaerosols at schools from two different types of areas, urban and rural. A methodology based upon passive sampling was applied to evaluate fungi, bacteria and pollens, simultaneously with active sampling for fungi and bacterial assessment. Results showed very good correlations between sampling methods, especially for summer season. Passive sampling methodologies presented advantages such as no need of specifi c and expensive equipment, and they allow achieving important qualitative information.The study was conducted in different periods of the year to study the seasonal variation of the bioaerosols. Fungi and pollen presented higher levels during the summer time whereas bacteria did not present a seasonal variation. Indoor to outdoor ratios were determined to assess the level of outdoor contamination upon the indoor environment. Levels of fungi were higher outdoor and bacteria presented higher concentrations indoors.Indoor levels of bioaerosols were assessed in primary schools of urban and rural areas, using the active method along with a passive sampling method. Very good correlations between methods were found which allow the use of the passive sampling method to supply important and reliable qualitative information of bioaerosols concentrations in indoor environments. Seasonal variation in bioaerosols concentrations were found for fungi and pollen. Concentrations of fungi and bacteria above AMV (Acceptable Maximum Value) were found for most of the studied classrooms showing the importance of this microenvironment for the high exposure of children to bioaerosols.