Harmonization of Air Quality Measurements at European Union Level

An overview is given of the harmonization work of air quality measurements led by the European Reference Lab. of Air Pollution (ERLAP)/JRC Ispra at EU level. The activityof the lab. is presented by giving a few examples of recent achievements, organisation of quality assurance/quality control programmes for current air quality directives and preparatory work for future regulations (VOCs0>JRC.(EI)-Environment Institut

BTX Monitoring Campaign in Brussels

Abstract not availableJRC.(EI)-Environment Institut

Population Exposure to Air Pollutants in Europe (PEOPLE)

The PEOPLE (Population Exposure to Air Pollutants in Europe) project results are presented. Air quality at the city scale is linked to the relationship between emissions and pollution dispersion. When considering different samples of the city population, transportation and tobacco smoke are important factors that define exposure to pollution. The support of the media and thousands of citizens across 6 European cities enabled the production of good scientific data while generating information relevant to both policy development and awareness raising of the public to air pollution.JRC.DDG.H.4-Transport and air qualit

Interlaboratory Exercises for Voltile Organic Compound Determination.

Abstract not availableJRC.H-Institute for environment and sustainability (Ispra

Radial Diffusive Sampler for the Determination of 8-Hour Ambient Ozone Concentrations

The 8-hour ozone Radial diffusive sampler was evaluated according to the CEN protocol for the validation of diffusive samplers and to the O3 European Directive. All the parameters regarding the sampler characteristics (blank value, desorption efficiency, storage before and after exposure, sampler integrity) were found to be consistent with the requirements of this protocol apart from the blank value which must be evaluated and subtracted at each sampling. The nominal uptake rate determined in laboratory conditions was 81.5 ± 0.3 cm³.min-1. However, the uptake rate depends on the mass uptake, temperature and on the combination of temperature and humidity while it was found independent of the wind velocity and direction. Based on laboratory experiments, an empirical model has been established. Using this model, the agreement between the radial sampler and the reference methods was improved compared to the radial sampler results using the nominal uptake rate. This improvement was observed with the results of an international intercomparison of diffusive samplers and with the routine measurements at 5 European monitoring stations showing different meteorological and emission conditions. In this study, it was shown that by using the model equation of uptake rate, the data quality objective of 30 % for the expanded uncertainty is easily attained. Therefore, the ozone Radial sampler is an appropriate indicative method for monitoring ambient ozone.JRC.F.8-Sustainable Transpor

Modification of the Palmes diffusion tube and semi-empirical modelling of the uptake rate for monitoring nitrogen dioxide

Hereafter, a modification of the traditional Palmes diffusion tube by fitting a membrane at the open end of the tube is presented. The membrane is placed to avoid the effect of turbulence due to wind speed. Further optimisations of the volume of absorbent and number of meshes retaining the absorbent are also described. Finally, the sampler is placed in an air proof container and is ready to use in order to improve the quality of measurement. In order to evaluate the performance of the membrane-closed Palmes diffusion tube to monitor nitrogen dioxide (NO2), experiments were carried out in an exposure chamber. The relative effect of NO2, temperature, humidity, averaging time and wind speed on the uptake rate of the sampler were then studied. Among the uncontrolled variables, temperature and humidity are found to be the most important ones leading to variability of the uptake rate. Two equations, used to estimate the uptake rate are established. These equations were then applied on some field data and laboratory inter-comparison tests. The agreement between the chemiluminescence method and diffusive samplers changes from 20% of mean bias with the traditional Palmes diffusion tubes to 5% of mean bias with the membraneclosed Palmes tube (MCPT) at the same monitoring site. In the laboratory inter-comparison, the MCPT has shown to be able to correctly measure NO2 under two extreme exposure conditions in contrast with other diffusive samplers. The uncertainty of the sampler is evaluated. It fulfils the European Directive data quality objective of 25% for accuracy and therefore the sampler qualifies as an indicative method for NO2 monitoring.JRC.H.4-Transport and air qualit

Modelling of the Uptake Rate of the Nitrogen Dioxide Palmes Diffusive Sampler Based on the Effect of Environmental Factors

The influence of environmental parameters on the uptake rate of the nitrogen dioxide (NO2) Palmes diffusive sampler was investigated. The main factors affecting the uptake rate were found to be wind speed, the preponderant factor, followed by relative humidity and temperature. The NO2 concentration and exposure time, as well as the interactions among the factors were not found to have a significant influence on the uptake rate of the Palmes sampler. As a result, a model able to predict the uptake rate of the Palmes sampler was established. In addition, by using the model-predicted uptake rate, the agreement between chemiluminescence and the Palmes sampler during the field tests was improved. The NO2 Palmes diffusive sampler was shown to comply with the requirement on accuracy defined by the European Directive for the indicative methods of measurements.JRC.H.4-Transport and air qualit

Personal exposure to PM2.5 among high-school students in Milan and background measurements: The EuroLifeNet study

As part of the EuroLifeNet program we measured personal exposure to PM2.5 in 90 pupils attending three schools in Milan, over a three-week period spanning November and December 2006, using a portable light-scattering nephelometer. The primary aim was to investigate the relationship between personal exposure to PM2.5 and background measurements obtained from a fixed monitoring station. Pearson’s correlation coefficient between sampled daily mean exposures and reference values from background station varied from 0.64 to 0.75, with an overall value of 0.63, indicating good agreement. We also estimated that about 40% of the variability in the mean daily personal exposure at the three schools was due to variability in background exposure, the remaining 60% due to between-subject differences in exposures or to other sources of error.JRC.C.5-Air and Climat

Mapping of Ozone Levels during a Photochemical Episode Using Fast Response Diffusive Sampler. An Application: Varese Monitoring Campaign.

Abstract not availableJRC.(EI)-Environment Institut