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Until now, only a few studies have addressed the effects of climatic changes on the microclimate in indoor areas. Although global warming presents a problem worldwide, the extent of climate change varies greatly according to region. In this work, climatic changes and their influences on indoor areas in Germany are discussed. Air temperatures, quantity of summer days, sunshine hours and precipitation were extracted from the databases of the German National Meteorological Service. In addition, data on ozone, nitrogen dioxide, PM10 and PM2.5 were collected from eight monitoring stations in different urban locations. With the aid of single-box models, the effects of these parameters on indoor air were assessed. Furthermore, temperature and humidity measurements were performed in a thermally insulated house during a 14-day period of fine weather. Finally, trends for the indoor temperature through to the year 2040 were estimated. With the current thermal insulation standards, effects of climate change are associated with an increase in indoor temperatures, which can easily lead to overheating in the event of heatwaves. Nitrogen oxides and ozone are subject to strong daily and seasonal fluctuations. Particle concentrations are declining in Germany. The entry of outdoor air contaminants into the indoor area is essentially dependent on the air exchange. On the whole, measurements and simulations show that climate change substantially influences the indoor air quality. This will have consequences in the medium term as regards measures for thermal insulation and for regulation of the air exchange in private and public buildings.

Human civilization is currently facing two particular challenges: population growth with a strong trend towards urbanization and climate change. The latter is now no longer seriously questioned. The primary concern is to limit anthropogenic climate change and to adapt our societies to its effects. Schools are a key part of the structure of our societies. If future generations are to take control of the manifold global problems, we have to offer our children the best possible infrastructure for their education: not only in terms of the didactic concepts, but also with regard to the climatic conditions in the school environment. Between the ages of 6 and 19, children spend up to 8 h a day in classrooms. The conditions are, however, often inacceptable and regardless of the geographic situation, allthe current studies report similar problems: classrooms being too small for the high number of school children, poor ventilation concepts, considerable outdoor air pollution and strong sources of indoor air pollution.There have been discussions about a beneficial and healthy air quality in classrooms for many years now and in recent years extensive studies have been carried out worldwide. The problems have been clearly outlined on a scientific level and there are prudent and feasible concepts to improve the situation. The growing number of publications also highlights the importance of this subject. High carbon dioxide concentrations in classrooms, which indicate poor ventilation conditions,and the increasing particle matter in urban outdoor air have, in particular, beenidentified as primary causes of poor indoor air quality in schools. Despite this, the conditions in most schools continue to be in need of improvement. There are many reasons for this. In some cases, the local administrative bodies do not have the budgets required to address such concerns, in other cases regulations and laws stand in contradiction to the demands for better indoor air quality, and sometimes the problems are simply ignored.This review summarizes the current results and knowledge gained from the scientific literature on air quality in classrooms. Possible scenarios for the future are discussed and guideline values proposed which can serve to help authorities, government organizations and commissions improve the situation on a global level.

Im Rahmen der Richtlinienarbeit der Kommission Reinhaltung der Luft im VDI und DIN - Normenausschuss KRdL wurde ein Ringversuch zur Validierung des Analysenverfahrens für Phthalate in der Innenraumluft durchgeführt. Dabei wurden die beiden in der künftigen Richtlinie beschriebenen Analysenverfahren der Thermodesorption von Adsorptionsröhrchen sowie der Lösemittelextraktion von Florisilröhrchen mit jeweils anschließender Gaschromatographie und Massenspektrometrie (GC/MS) erprobt. Die Ergebnisse des Ringversuchs belegen die Vergleichbarkeit der beiden Verfahren. Auch die Richtigkeit der Ergebnisse im Rahmen einer akzeptablen Streuung sowie die Praktikabilität in der Praxis konnten bestätigt werden. Weiterhin wurden wichtige Erkenntnisse zur Minimierung der Blindwerte erarbeitet.

The aim of this work was to investigate ultrafine particles (

The release of ultra-fine particles (UFP, d < 0.1 µm) from hardcopy devices such as laser printers into the indoor environment is currently a topic of high concern. The general emission behavior of a printer can be examined by conducting emission test chamber measurements with particle-counting devices. Chamber experiments with modified laser printers operated without toner or paper also revealed UFP emissions. On the basis of these results we reasonably doubt the opinion that UFPs primarily originate from the toner. Instead, the high-temperature fuser unit is assumed to be one source for ultra-fine particle emission. UFP release typically follows the flow path of the cooling air which may leave the printer casing at various points (e.g. the paper tray). This limits the usability of the commercial filter systems available because the released particles could leave the printer without passing through the filter. Chamber measurements with various filter systems retrofitted to a laser printer demonstrate different efficiencies of UFP reduction. Complementary experiments were carried out in an office room. Here the decay of the particle concentration after a print job was about ten times slower than in the test chamber. A toxicological assessment of the emitted particles requires that their chemical composition be known. Due to the low mass of the released UFPs chemical analysis needs a prior enrichment on a feasible media. Experiments using electrostatic precipitation showed a flame retardant (tri-xylyl phosphate) whose concentration on the media was dependent on the number of pages printed. Whether this compound was particle-bound could not be determined.

Emissionen von Produkten stehen zunehmend im Fokus des öffentlichen Interesses. Aufgrund der hohen wirtschaftlichen Bedeutung der Emissionseigenschaften beschäftigen sich Hersteller schon in der Entwicklungsphase neuer Produkte zunehmend mit dieser Thematik. Daraus leitet sich der Bedarf an Schnelltestmethoden ab, mit denen die Emissionen von Vor-, Zwischen- und Endprodukten verlässlich, schnell und kostengünstig untersucht werden können. Als möglicher Schnelltest wird die Methode der Thermoextraktion vorgestellt. Dabei kamen zwei verschiedene kommerzielle Geräte (ThermoExtraktor und Mikrokammer) zum Einsatz, mit denen verschiedene Fußbodenbeläge und ein ABS-Kunststoffgranulat exemplarisch untersucht wurden. Die Ergebnisse zeigen mit den entsprechenden Prüfkammeruntersuchungen gute Übereinstimmungen. Mit dem ThermoExtraktor und der Mikrokammer stehen für einen Schnelltest Geräte zur Verfügung, deren Einsatz im Rahmen von Produktentwicklung, werkseigener Produktionskontrolle und Fremdüberwachung möglich erscheint.

Phthalic acid esters and phosphororganic compounds (POC) are generally known as semivolatile organic compounds (SVOCs) and are frequently utilized as plasticizers and flame retardants in commercial products. In the indoor environment, both compound groups are released from a number of sources under normal living conditions and accumulate in air and dust. Therefore, inhalation of air and ingestion of house dust have to be considered as important pathways for the assessment of exposure in living habitats. Especially in the case of very young children, the oral and dermal uptake from house dust might be of relevance for risk assessment. A critical evaluation of indoor exposure to phthalates and POC requires the determination of the target compounds in indoor air and house dust as well as emission studies. The latter are usually carried out under controlled conditions in emission test chambers or cells. Furthermore, chamber testing enables the determination of condensable compounds by fogging sampling. In the case of automobiles, specific scenarios have been developed to study material emissions on a test stand or to evaluate the exposure of users while the vehicle is driving. In this review, results from several studies are summarized and compared for seven phthalic esters and eight POC. The available data for room air and dust differ widely depending on investigated compound and compartment. Room air studies mostly include only a limited number of measurements, which makes a statistical evaluation difficult. The situation is much better for house dust measurements. However, the composition of house dust is very inhomogeneous and the result is strongly dependent on the particle size distribution used for analysis. Results of emission studies are presented for building products, electronic equipment, and automobiles. Daily rates for inhalation and dust ingestion of phthalic esters and POC were calculated from 95-percentiles or maximum values. A comparison of the data with results from human biomonitoring studies reveals that only a small portion of intake takes place via the air and dust paths.

Organophosphate esters, halogenated and non-halogenated, are frequently used for fire protection of building materials. With regard to toxicological profiles it is desired to avoid human exposure in the indoor environment. Moreover, some hazardous VOCs detected in indoor air are directly linked to the utilization of flame retardants. In this study different polyurethane products for building and indoor use treated with organophosphate flame retardants were tested in 1 m3 emission test chambers. Emissions of flame retardants and degradation products were measured under living conditions. A polyurethane hard foam sample showed area specific emissions rates > 100 µg/m²h for the compound triethyl.

The vapor pressure is an important parameter for estimating the fate of chemical substances in the indoor environment. For compounds of low volatility, a combination of the KNUDSEN effusion method and the LANGMUIR free evaporation method enables the precise measurement of vapor pressures over a wide temperature range. This is demonstrated for the fungicides Dichlofluanid and Tolylfluanid and the insecticide a-Endosulfan. Saturation concentrations were estimated and compared with results from test chamber experiments carried out under indoor conditions.

The Field and Laboratory Emission (FLEC) has been designed for VOC emission testing of material surfaces. Knowledge about the air flow field in the cell compartment is highly desired, as the air velocity at the sample surface may considerably influence the emission behaviour. A simple mathematical approach of flow theory predicted an unevenly distributed air flow into the FLEC. This could be confirmed by air velocity measurements using a self-constructed hot-wire anemometer. With a total flow of 250 ml min -1, air velocities measured at the surface ranged from