BS EN 12341-2014

BSI Standards Publication BS EN 12341:2014 Ambient air — Standard gravimetric measurement method for the determination of the PM 10or PM 2,5mass concentration of suspended particulate matterBS EN 12341:2014 BRITISH STANDARD National foreword This British Standard is the UK implementation of EN 12341:2014. It supersedes BS EN 12341:1999 and BS EN 14907:2005 which are withdrawn. The UK participation in its preparation was entrusted to Technical Committee EH/2/3, Ambient atmospheres. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. © The British Standards Institution 2014. Published by BSI Standards Limited 2014 ISBN 978 0 580 78524 5 ICS 13.040.20 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2014. Amendments/corrigenda issued since publication Date T e x t a f f e c t e dBS EN 12341:2014EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 12341 May 2014 ICS 13.040.20 Supersedes EN 12341:1998, EN 14907:2005 English Version Ambient air - Standard gravimetric measurement method for the determination of the PM 10or PM 2,5 mass concentration of suspended particulate matter Air ambiant - Méthode normalisée de mesurage gravimétrique pour la détermination de la concentration massique MP 10 ou MP 2,5 de matière particulaire en suspension Außenluft - Gravimetrisches Standardmessverfahren für die Bestimmung der PM 10- oder PM 2,5-Massenkonzentration des Schwebstaubes This European Standard was approved by CEN on 10 April 2014. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels © 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12341:2014 E BS EN 12341:2014 EN 12341:2014 (E) 2 Contents Page Foreword 4 Introduction .5 1 Scope 7 2 Normative references 8 3 Terms, definitions, symbols and abbreviations .8 3.1 Terms and definitions .8 3.2 Symbols and abbreviations . 10 4 Principle . 12 4.1 Description of the standard measuring principle 12 4.2 Initial use and procedures for ongoing QA/QC . 12 5 Equipment and facilities 13 5.1 Sampling system components 13 5.1.1 General . 13 5.1.2 Standard inlet design . 14 5.1.3 Connecting pipe work 15 5.1.4 Filter holder and filter . 15 5.1.5 Flow control system . 16 5.1.6 Sampling period 16 5.1.7 Leak tightness of the sampling system 16 5.1.8 Storage conditions . 17 5.2 Weighing facilities 17 5.2.1 General . 17 5.2.2 Weighing room 18 5.2.3 Balance 18 6 Filter conditioning, sampling and weighing procedures 19 6.1 General . 19 6.2 Filter conditioning and weighing prior to sampling 19 6.3 Sampling procedure . 20 6.3.1 Filter cassette loading 20 6.3.2 Filter sampling 20 6.3.3 Sample storage and transport procedures 20 6.4 Filter conditioning and weighing after sampling . 20 6.5 Weighing room procedures . 21 6.6 Filter blanks for ongoing quality control 21 6.6.1 General . 21 6.6.2 Weighing room blanks . 21 6.6.3 Field blanks . 22 7 Ongoing quality control . 22 7.1 General . 22 7.2 Frequency of calibrations, checks and maintenance . 22 7.3 Maintenance of the sampling system . 23 7.4 Checks of sampler sensors . 23 7.5 Calibration of sampler sensors . 24 7.6 Checks of the sampler flow rate 24 7.7 Calibration of the sampler flow rate 24 7.8 Leak check of the sampling system . 24 7.9 Checks of weighing room sensors . 24 7.10 Calibration of weighing room sensors . 25 7.11 Balance 25 BS EN 12341:2014 EN 12341:2014 (E) 3 8 Expression of results 25 9 Performance characteristics of the method . 25 9.1 General . 25 9.2 GUM concept . 25 9.3 Individual uncertainty sources 27 9.3.1 General . 27 9.3.2 Collected particulate mass . 27 9.3.3 Time (t) 30 9.3.4 Uncertainty budget 30 9.4 Expanded uncertainty vs. EU Data Quality Objectives . 32 Annex A (normative) Design drawing of standard inlet for the sampling of PM 10and PM 2,534 Annex B (normative) Other samplers . 35 Annex C (informative) Scheme of PM standard sampler 44 Annex D (informative) Suitability tests for filters. 45 Annex E (normative) Initial suitability testing of weighing facilities . 47 Annex F (informative) Results of experimental work 48 Annex G (informative) Impactor efficiency . 50 Bibliography 52 BS EN 12341:2014 EN 12341:2014 (E) 4 Foreword This document (EN 12341:2014) has been prepared by Technical Committee CEN/TC 264 “Air quality”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2014 and conflicting national standards shall be withdrawn at the latest by November 2014. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 12341:1998 and EN 14907:2005. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association and supports Essential Requirements of the Council Directive 2008/50/EC [1]. EN 12341:2014 includes the following significant technical changes with respect to EN 12341:1998 and EN 14907:2005: — this document is adapted from EN 14907:2005 due to consideration of best available technology; — the three different standard reference methods for PM 10described in EN 12341:1998 and the two different standard reference methods for PM 2,5described in EN 14907:2005 are replaced in this document by only one possible standard reference method for each of PM 10or PM 2,5 . According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom BS EN 12341:2014 EN 12341:2014 (E) 5 Introduction For air quality across the European Union to be assessed on a consistent basis, Member States need to employ standard measurement techniques and procedures. The aim of this European Standard is to present a harmonized methodology for monitoring the mass concentrations of suspended particulate matter (PM 10and PM 2,5respectively) in ambient air, following Directive 2008/50/EC on ambient air quality and cleaner air for Europe [1] which sets the parameters specific to the assessment of ambient concentration levels of particulate matter. NOTE In principle, the methodology described in this European Standard may also be used for measurement of mass concentrations of other PM fractions such as PM 1. However, this European Standard does not describe standardized sampling inlets for such fractions. This European Standard merges the earlier European Standards EN 12341:1998 [2] and EN 14907:2005 [3] with the aim of harmonizing the very similar procedures that are used to measure mass concentrations of both fractions of particulate matter in ambient air. The European Standard method described in this European Standard is focussed primarily on harmonization and improvement of the data quality of measurement methods used in monitoring networks, with regard to avoiding unnecessary discontinuities with historical data. It is a method that is suited for practical use in routine monitoring, but not necessarily the method with the highest metrological quality. There are no traceable reference standards for PM 10or PM 2,5measurements. Therefore, the standard method defines the measured quantity by convention, specifically by the sample inlet design and associated operational parameters covering the whole measurement process. This European Standard contains: — a description of a manual gravimetric standard measurement method for PM 10or PM 2,5using sequential samplers or single-filter samplers; — a summary of performance requirements of the method; — requirements for suitability testing of facilities and equipment on initial application of the method; — requirements for ongoing quality assurance / quality control when applying the method in the field; — the assessment of measurement uncertainty of the results of this European Standard method; — (tentative) criteria and test methods for the evaluation of the suitability of filters for application using this method. The performance characteristics and requirements described in this European Standard were partly determined in different comparative and validation trials. The trials were sponsored by the European Commission and the European Free Trade Association. However, for lack of appropriate criteria and protocols to test filters for fitness for purpose, considerable differences may exist between results obtained when using different filter types, and even filters of the same type. For example, differences of up to 15 % have been found when applying different brands of quartz-fibre filters in parallel measurements of PM 10for concentrations around 50 % of the daily limit value [4]. This may have implications for results produced by automated measurement systems as these are calibrated by comparison of results with those obtained using reference samplers (CEN/TS 16450:2013 [5]). In principle, the filters collected for the purpose of determining the mass concentrations of PM 10or PM 2,5can be used for further speciation, e.g. for the determination of concentrations of: — heavy metals and polycyclic aromatic hydrocarbons (see EN 14902 [6] and EN 15549 [7]) in conformity with Directive 2004/107/EC [8], BS EN 12341:2014 EN 12341:2014 (E) 6 — constituents of PM 2,5(see CEN/TR 16243 [9] and CEN/TR 16269 [10]) to be used for source apportionment as required by Directive 2008/50/EC. Additional requirements might have to be considered for those purposes (e.g. blank values of chemical constituents). However, the requirements of this European Standard are targeted firstly towards obtaining optimum results for the measurement of mass concentrations of PM 10or PM 2,5 . BS EN 12341:2014 EN 12341:2014 (E) 7 1 Scope This European Standard describes a standard method for determining the PM 10or PM 2,5mass concentrations of suspended particulate matter in ambient air by sampling the particulate matter on filters and weighing them by means of a balance. Measurements are performed with samplers with inlet designs as specified in Annex A, operating at a nominal flow rate of 2,3 m 3 /h, over a nominal sampling period of 24 h. Measurement results are expressed in µg/m 3 , where the volume of air is the volume at ambient conditions near the inlet at the time of sampling. The range of application of this European Standard is from approximately 1 µg/m 3(i.e. the limit of detection of the standard measurement method expressed as its uncertainty) up to 150 µg/m 3for PM 10and 120 µg/m 3for PM 2,5 . NOTE 1 Although the European Standard is not validated for higher concentrations, its range of application could well be extended to ambient air concentrations up to circa 200 µg/m 3when using suitable filter materials (see 5.1.4). This European Standard describes procedures and gives requirements for the use of so-called sequential samplers, equipped with a filter changer, suitable for extended stand-alone operation. Sequential samplers are commonly used throughout the European Union for the measurement of concentrations in ambient air of PM 10or PM 2,5 . However, this European Standard does not exclude the use of single-filter samplers. This European Standard does not give procedures for the demonstration of equivalence of other sampler types, e.g. equipped with a different aerosol classifier and/or operating at different flow rates. Such procedures and requirements are given in detail in the Guide to the Demonstration of Equivalence of Ambient Air Monitoring Methods [11] and for automated continuous PM monitors (see CEN/TS 16450:2013). The present European Standard represents an evolution of earlier European Standards (EN 12341:1998 and EN 14907:2005) through the development of the 2,3 m 3 /h sampler to include constraints on the filter temperature during and after sampling and the ability to monitor temperatures at critical points in the sampling system. It is recommended that when equipment is procured it complies fully with the present European Standard. However, older versions of these 2,3 m 3 /h samplers that do not employ sheath air cooling, the ability to cool filters after sampling, or the ability to monitor temperatures at critical points in the sampling system have a special status in terms of their use as reference samplers. Historical results obtained using these samplers will remain valid. These samplers can still be used for monitoring purposes and for equivalence trials, provided that a well justified additional allowance is made to their uncertainties (see Annex B). In addition, three specific sampling systems – the “long nozzle” 2,3 m 3 /h sampler and the 68 m 3 /h sampler for PM 10in EN 12341:1998, and the 30 m 3 /h PM 2,5inlet in EN 14907:2005 – also have a special status in terms of their use as reference samplers. Historical results obtained using these samplers will remain valid. These samplers can still be used for monitoring purposes and for equivalence trials, provided that a well-justified additional allowance is made to their uncertai