Results of the European Intercomparison exercise for Receptor Models 2011-2012. Part I

Receptor models are commonly used to identify the sources of ambient particulate matter (PM) in Europe. However, the use of different tools and methodological approaches make it difficult to compare the results of different studies. In order to promote harmonization in this field an intercomparison exercise involving 16 expert groups was organized and evaluated by the JRC with the collaboration of European experts in the field. The test database consisted of 178 PM2.5 speciated samples deriving from two real-world re-arranged DB Participants were asked to scrutinize the database in order to identify, solve and report typical imperfections of real world DBs (missing values, values below detection limits, outliers, unusual uncertainty patterns, etc...). The reported solutions included the number and label of the identified sources, their contribution estimation (SCE) and uncertainty. The exercise was evaluated using a new methodology developed on purpose The majority of the solutions reconstructed the PM mass satisfactorily while the number of sources identified in the different solutions was variable. The correspondence of every source/factor to a source category was checked by comparing its chemical profile and time trend with all the other members of the same category and with reference source profiles, when available. The SCEs of the different solutions were compared with a reference value obtained by robust analysis (standard ISO 5725-5). The acceptability criterion was set to 50% standard uncertainty. More than 90% of the 182 tested profiles passed the preliminary tests and 86% of the assessed source/factor contribution estimations met the acceptability criterion. This result indicates a good general agreement between the performances of the different participants and models.JRC.H.2-Air and Climat

Structural assessment and lateral\u2013torsional buckling design of glass beams restrained by continuous sealant joints

Glass is largely used in practice as a structural material, e.g. as beam and plate elements able to carry loads. Their structural interaction is often provided by mechanical connections, although recent trends are moving toward the minimization of metal components and the primary involvement of adhesives or silicone structural joints working as partially rigid continuous restraints. In this work, the lateral\u2013torsional buckling (LTB) behavior of glass beams laterally restrained by continuous silicone joints is assessed. Based on earlier contributions of literature and extended parametric Finite-Element (FE) numerical investigations, closed-form solutions are suggested for the estimation of their Euler\u2019s critical buckling moment under various loading conditions. Finally, by means of more detailed incremental nonlinear analyses, their global LTB response is also investigated, to assess their sensitivity to initial geometrical imperfections as well as their prevalent LTB failure mechanism. In conclusion, a generalized buckling design curve able to account for the structural contribution provided by structural silicone joints is proposed for a rational and conservative LTB verification

A Quality Assurance and Control Program for PM2.5 and PM10 measurements in European Air Quality Monitoring Networks

To harmonize PM measurements in the European Union, the JRC together with the AQUILA Network of National Air Quality Reference Laboratories organized a PM QA/QC program. From 2006 – 2009, the JRC, equipped with a mobile laboratory, measured in 18 Member States, for a duration of two weeks each, PM10 and PM2.5 in parallel to measurement sites of local networks and to the National Reference Laboratories. The main goals of the project were to find out to which degree PM measurements performed in the Member States agree with the requirements of the relevant EU directive and how correction factors for automatic analyzers were applied.JRC.DDG.H.2-Climate change and air qualit

Ex-ante assessment of air quality in EUSALPS and EUSAIR macro-regions: Towards a coordinated science-based approach in support of policy development

The study focuses on the air quality issues of the EUSALP and EUSAIR macro-regions and discusses areas for improvement to be considered in the development of their future strategies. Key areas where action is expected to be most effective, considering the particular features of the macro-regions, are those of residential heating, traffic and shipping emissions. A strengthened collaboration at the macro-regional level, especially between EU and non-EU countries, has the potential to boost environmental policies by promoting collaboration and exchange of best practices among cities and regions that face similar challenges.JRC.C.5-Air and Climat

The Evaluation of the Interlaboratory Comparison Exercise for SO2, CO, O3, NO and NO2 19.- 22. October 2009

From the 19th to the 22nd of October 2009 in Ispra (IT), 8 Laboratories of AQUILA (Network of European Air Quality Reference Laboratories) met at an interlaboratory comparison exercise to evaluate their proficiency in the analysis of inorganic gaseous pollutants covered by European Air Quality Directives (SO2, CO, NO, NO2 and O3). The proficiency evaluation, where each participant¿s bias was compared to two criteria, provides information on the current situation and capabilities to the European Commission and can be used by participants in their quality control system. In terms of criteria imposed by the European Commission, 85% of the results reported by AQUILA laboratories were good both in terms of measured values and reported uncertainties. Another 14% of the results had good measured values, but the reported uncertainties were either too high (6%) or too small (8%). The comparability of results among AQUILA participants is satisfactory for O3, CO and NO measurement methods. This is not the case for SO2 and NO2 which comparability in the present exercise is not satisfactory with respect to the settled quality criteria.JRC.DDG.H.4-Transport and air qualit

The evaluation of the interlaboratory comparison exercise for SO2, CO, O3, NO and NO2 14-17 June 2010

From the 14th to the 17th of June 2010 in Ispra (IT), 9 Laboratories of AQUILA (Network of European Air Quality Reference Laboratories) met at an interlaboratory comparison exercise to evaluate their proficiency in the analysis of inorganic gaseous pollutants covered by European Directive about air quality (SO2, CO, NO, NO2 and O3). The proficiency evaluation, where each participant’s bias was compared to two criteria, provides information on the current situation and capabilities to the European Commission and can be used by participants in their quality control system. On the basis of criteria imposed by the European Commission, 85% of the results reported by AQUILA laboratories were good both in terms of measured values and reported uncertainties. Another 12% of the results had good measured values, but the reported uncertainties were either too high (8%) or too small (4%). Comparability of results among AQUILA participants at the highest concentration level, excluding outliers, is acceptable in NO, CO and O3 measurements while NO2 and SO2 measurement methods showed less satisfactory results.JRC.H.2-Climate change and air qualit

14 th Conference on Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes -2-6

Abstract: Receptor Models identify pollution sources by solving a mass balance equation using measured chemical composition of samples in combination with known source profiles. In the last ten years, the number of receptor modelling studies performed on filed air quality data exponentially increased. Among these, 39% are performed with Positive Matrix Factorization (PMF, ME), 23% with Principal Component Analysis (PCA, APCA), 13% with Chemical Mass Balance (CMB), 10% with Factor Analysis (FA, APCFA) and 10% with the APEG model. This approach has been extensively used in North America and South-eastern Asia mainly on particulate matter. Also in Europe it found wide acceptance and contributed to the identification of sources in support of remediation measures design. With the aim of harmonizing the activity in receptor modelling in Europe and supporting the implementation of Directive 2008/50/EC, an evaluation of the current state of this methodology in Europe was carried out highlighting the following needs: improving data collection, harmonizing analytical protocols by setting up common criteria, promoting advanced tools, establishing criteria for the assessment and, comparing receptor model performances. In this study we discuss the sources of uncertainty in the input data and the common approaches used to express them when preparing model input. We also analyze the contribution to the uncertainty deriving from critical model steps and the methodologies used to identify and reduce them. On the basis of the previous discussion we propose a sketch of Common QA/QC protocol. Improving comparability and reliability of receptor models can be achieved by performing inter-comparison exercises. A community-wide inter-comparison organized and evaluated by the JRC within the framework of FAIRMODE is currently in progress. We describe the methodology for the evaluation and comparison of receptor models used in this exercise. Key words: source apportionment, inter-comparison, receptor models, FAIRMODE INTRODUCTION Receptor Models (RM) are used to identify the causes of pollution by analyzing concentrations and other parameters measured at one or more specific sites (receptor). In principle, RM are based on statistical analysis. At the first step they do not consider physical and chemical processes but evolved hybrid models can process additional information to constrain results. Most typical hybrid models are those using wind direction and speed or air masses trajectories to infer the geographical provenience of pollutants

Sustainable use of biomass in residential sector

In the framework of the EU Strategy for the Danube Region (EUSDR), biomass burning for heat production in households has emerged as a major issue where a better balance between “decarbonisation” benefits and negative impacts on air quality, the environment and human health is needed. This report provides a synthesis of the current knowledge, leading the reader from problem formulation, to impact analysis and suggested solutions, both from the technical and regulatory points of view.JRC.C.5-Air and Climat

The Evaluation of the Interlaboratory Comparison Exercise for SO2, O3, NO and NO2 Langen 20th-25th September 2009

From the 20th to the 25th of September 2009 in Langen (DE), 4 national reference laboratories (NRL) of AQUILA network and 3 laboratories of the World Health Organisation (WHO) Euro-Region met for an interlaboratory comparison exercise (IE) to evaluate their proficiency in the analysis of inorganic gaseous pollutants covered by European Air Quality Directives (SO2, NO, NO2 and O3). Most of the laboratories participating in the IE used automated CEN reference methods, which are mandatory in the EU, while some laboratories of the WHO Euro-Region performed analysis using manual methods. In this report proficiency evaluation was made at different degrees for each laboratory taking into account the differences in the methodologies and the completeness of the information provided by participants. For the laboratories who expressed their uncertainty, performance was evaluated using two criteria, providing information on their proficiency to the European Commission and supporting the national quality control systems. In terms of criteria imposed by the European Commission (that are not mandatory for WHO laboratories), 71% of the results reported by National Reference Laboratories (AQUILA network) were good both in terms of measured values and reported uncertainties. Another 23% of the results had good measured values, but the reported uncertainties were either too high (19%) or too small (4%). There were no questionable nor unacceptable values. AQUILA laboratories presented good comparability among participants for NO2, O3, and SO2. The relative reproducibility limit for NO was above the objective deriving from the standard deviation for proficiency assessment. For WHO laboratories using automated techniques, the results are satisfactory for SO2, NO2 and NO measurement methods, while one laboratory needs further investigation of their O3 measurements. The laboratory using manual methods presented results comparable to those of the automated methods for NO and O3 but there were questionable results for NO2 and SO2 and unsatisfactory results for NO2.JRC.DDG.H.4-Transport and air qualit

Comparison of source apportionment approaches and analysis of non-linearity in a real case model application

Abstract. The response of particulate matter (PM) concentrations to emission reductions was analysed by assessing the results obtained with two different source apportionment approaches. The brute force (BF) method source impacts, computed at various emission reduction levels using two chemical transport models (CAMx and FARM), were compared with the contributions obtained with the tagged species (TS) approach (CAMx with the PSAT module). The study focused on the main sources of secondary inorganic aerosol precursors in the Po Valley (northern Italy): agriculture, road transport, industry and residential combustion. The interaction terms between different sources obtained from a factor decomposition analysis were used as indicators of non-linear PM10 concentration responses to individual source emission reductions. Moreover, such interaction terms were analysed in light of the free ammonia / total nitrate gas ratio to determine the relationships between the chemical regime and the non-linearity at selected sites. The impacts of the different sources were not proportional to the emission reductions, and such non-linearity was most relevant for 100 % emission reduction levels compared with smaller reduction levels (50 % and 20 %). Such differences between emission reduction levels were connected to the extent to which they modify the chemical regime in the base case. Non-linearity was mainly associated with agriculture and the interaction of this source with road transport and, to a lesser extent, with industry. Actually, the mass concentrations of PM10 allocated to agriculture by the TS and BF approaches were significantly different when a 100 % emission reduction was applied. However, in many situations the non-linearity in PM10 annual average source allocation was negligible, and the TS and BF approaches provided comparable results. PM mass concentrations attributed to the same sources by TS and BF were highly comparable in terms of spatial patterns and quantification of the source allocation for industry, transport and residential combustion. The conclusions obtained in this study for PM10 are also applicable to PM2.5