M/503 - Ambient Air Quality

This European Standard specifies a method for the determination of the mass concentration of water soluble NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+, Ca2+ in PM2,5 as deposited on filters.
This European Standard describes a measurement method which comprises sampling of anions and cations as part of the PM2,5 particulate phase, sample extraction and analysis of anions and cations by ion chromatography.
NOTE 1   Alternatively, cations, excluding ammonium, can be analysed by inductively coupled plasma optical emission spectrometry (ICP-OES). Ammonium can also be analysed by photometry or conductometry.
This European Standard can be used for the measurements of anions and cations as required by Directive 2008/50/EC. The method does not take into account the possible losses  during sampling due to evaporation.
NOTE 2   NO3-, Cl-, NH4+ are part of the volatile fraction of PM2,5, and the concentrations determined using this standard can be used as minimum values for the concentrations of these ions in PM2,5. NO3-, NH4+, Cl- are usually 0 % to 30 % underestimated due to evaporational losses from the filter during sampling.
This European Standard may be used at rural and urban background sites and road sites that are in accordance with the siting criteria of Directive 2008/50/EC.
This European Standard is applicable to the measurement of anion/cations in PM2,5 samples corresponding to mass concentrations between approximately 1 μg/m3  (i.e. the limit of detection of the standard measurement method (EN 12341) expressed as its uncertainty) up to 120 μg/m3.
The validated range of the anion and cation concentrations based on the field validation measurements is presented in Table 1.
See Annex F for the statistical analysis of the field validation measurements.

In order to be in compliance with EU Air Quality Directive requirements, the reference methods given in the Directive for the measurement of mass concentrations of particulate matter are not commonly used for operation in routine monitoring networks. These networks usually apply automated continuous measurement systems (AMS), such as those based on the use of oscillating microbalances or ß-ray attenuation, and on in-situ optical methods. Such AMS are typically capable of producing 24-hour average measurement values over a measurement range up to 1000 µg/m3 and 1-hour average measurement values up to 10000 µg/m3, if applicable, where the volume of air is the volume at ambient conditions near the inlet at the time of sampling.
The 1-hour average values may be used for:
- direct information of the public,
- aggregation to produce daily or yearly average concentration values for regulatory reporting purposes.
EU Air Quality Directive 2008/50/EC allows the use of such systems after demonstration of equivalence with the reference method, i.e. after demonstration that these systems meet the Data Quality Objectives for continuous measurements.
This standard lays down the minimum performance requirements and test procedures for the selection of appropriate AMS for particulate matter (type approval). This includes the evaluation of its equivalence with the reference method.
Further, this standard describes minimum requirements for ongoing quality assurance - quality control (QA/QC) of AMS deployed in the field. These requirements are necessary to ensure that uncertainties of measured concentrations are kept within the required limits during extended periods of continuous monitoring in the field, and include procedures for maintenance, calibration and control checks. Additional procedures are described that determine whether an instrument's equivalence to the reference method is maintained through possible pollution climate changes, over periods longer than five years.
Lastly, this standard describes requirements and procedures for the treatment and validation of raw measurement data that are to be used for the assembly of daily or yearly average concentration values. Experiences with existing methods for data treatment and validation - for similar AMS - have learnt that the different ways of data treatment and validation applied may lead to significant differences in reported results for similar datasets.
When the standard is used for other purposes than the EU Directive, the range and uncertainty requirements may not apply.
This standard contains information for different groups of users. Clauses 5 and 6 and Annex A contain general information about the principles of automated continuous measurement systems for particulate matter, and relevant equipment.
Clause 7 and Annexes B and C are specifically directed towards test houses and laboratories that perform type-approval testing of automated continuous measurement systems for particulate matter. These clauses contain information about:
- type-approval test conditions, test procedures and test requirements,
- system performance requirements,
- evaluation of the type-approval test results,
- evaluation of the uncertainty of the measurement results of the automated continuous measurement systems for particulate matter based on the type-approval test results.
Clauses 8 to 11 are directed towards monitoring networks performing the practical measurements of particulate matter in ambient air. These clauses contain information about:
- initial installation of the system in the monitoring network and acceptance testing,
- ongoing quality assurance/quality control,
- verification of equivalence,
- treatment, validation and reporting of measurement results.

This European Standard gives guidance on the measurement of elemental carbon (EC) and organic carbon (OC) following the requirement for the networks of all EU member states to measure EC and OC in particulate matter from June 2010 at background sites according to the Council Directive 2008/50/EC on ambient air quality and cleaner air for Europe [1].
This European Standard describes the analytical procedures for determining EC and OC on quartz fibre filters as μg/cm2, and the subsequent calculation of concentrations as µg/m3. Sampling onto filters is to be done in accordance with EN 12341:2014 for PM2,5. The sampling process determines the size fraction of the particulate matter, the retention of semi-volatile material, and uptake/loss of volatile organic compounds on the filter at the time of sampling.
The same analysis method may also be used for smaller size fractions than PM2,5. Any possible additional artefacts for larger particles, e.g. pyrolysis or higher concentrations of carbonates, should be assessed.
The scope includes rural background, urban background, road side and industrial measurement sites, to allow the assessment of additional exposure of people in urban areas as stated in the objectives of the council directive and to achieve coherence in the European approach.
The applicable concentration range of the proposed method is limited by the optical correction and instrument applied in the analysis of EC and OC. This method was validated from 0,2 µg CEC/cm² and 1,8 µg COC/cm² to 38 µg CEC/cm² and 49 µg COC/cm² in the laboratory and to 16 µg CEC/cm² and 45 µg COC/cm² in the field.

This European Standard specifies a method for the determination of the mass concentration of water soluble NO3- (nitrate), SO42- (sulphate), Cl- (chloride), NH4+ (ammonium), Na+ (sodium), K+ (potassium), Mg2+ (magnesium), Ca2+ (calcium) in PM2,5 as deposited on filters.
This European Standard describes the analytical procedures for determining anions and cations as part of the PM2,5 particulate phase, sample extraction and analysis of anions and cations by ion chromatography. Sampling onto filters will be done in accordance with EN 12341 for PM2,5.
NOTE 1   Alternatively, cations, excluding ammonium, can be analysed by inductively coupled plasma optical emission spectrometry (ICP-OES). Ammonium can also be analysed by photometry or conductometry.
This European Standard can be used for the measurements of anions and cations as required by Directive 2008/50/EC. The method does not take into account the possible losses during sampling due to evaporation.
NOTE 2   NO3-, Cl-, NH4+ are part of the volatile fraction of PM2,5, and the concentrations determined using this standard can be used as minimum values for the concentrations of these ions in PM2,5. NO3-, NH4+, Cl- are usually up to 30 % underestimated due to evaporational losses from the filter during sampling.
This European Standard may be used at rural and urban background sites and road sites that are in accordance with the siting criteria of Directive 2008/50/EC.
This European Standard is applicable to the measurement of anion/cations in PM2,5 samples corresponding to PM2,5 mass concentrations between approximately 1 μg/m3 (i.e. the limit of detection of the standard measurement method (EN 12341) expressed as its uncertainty) up to 120 μg/m3.
The validated range of the anion and cation concentrations based on the field validation measurements is presented in Table 1.
(...)
See Annex A for the statistical analysis of the field validation measurements.

In order to be in compliance with EU Air Quality Directive requirements, the reference methods given in the Directive 2008/50/EC [1] for the measurement of mass concentrations of particulate matter are not commonly used for operation in routine monitoring networks. These networks usually apply automated continuous measurement systems (AMS), such as those based on the use of oscillating microbalances, ß-ray attenuation, or in-situ optical methods. Such AMS are typically capable of producing 24-hour average measurement values over a measurement range up to 1 000 µg/m3 and 1-hour average measurement values up to 10 000 µg/m3, if applicable, where the volume of air is the volume at ambient conditions near the inlet at the time of sampling.
The 1-hour average values may be used for:
a)   direct information of the public;
b)   aggregation to produce daily or yearly average concentration values for regulatory reporting purposes.
Directive 2008/50/EC allows the use of such systems after demonstration of equivalence with the reference method, i.e. after demonstration that these systems meet the Data Quality Objectives for continuous measurements. Guidelines for the demonstration of equivalence are given in Reference [2].
This European Standard lays down the minimum performance requirements and test procedures for the type approval of appropriate AMS for particulate matter. This includes the evaluation of its equivalence with the reference method as laid down in Directive 2008/50/EC.
Further, this European Standard describes minimum requirements for ongoing quality assurance – quality control (QA/QC) of AMS deployed in the field. These requirements are necessary to ensure that uncertainties of measured concentrations are kept within the required limits during extended periods of continuous monitoring in the field, and include procedures for maintenance, calibration and control checks.
Additional procedures are described that determine whether an instrument’s equivalence to the reference method is maintained through possible pollution climate changes, over periods longer than five years.
Lastly, this European Standard describes harmonized requirements and procedures for the treatment and validation of raw measurement data that are used for the assembly of daily or yearly average concentration values. Experience with existing methods for data treatment and validation – for similar AMS – has shown that the different ways of data treatment and validation applied may lead to significant differences in reported results for similar datasets [3].
When the European Standard is used for purposes other than measurements required by Directive 2008/50/EC, the range and uncertainty requirements may not apply.
This European Standard contains information for different groups of users.
Clauses 5 and 6 and Annex A contain general information about the principles of automated continuous measurement systems for particulate matter, and relevant equipment.
Clause 7 and Annexes B and C are specifically directed towards test houses and laboratories that perform type-approval testing of automated continuous measurement systems for particulate matter. These clauses contain information about:
c)   type-approval test conditions, test procedures and test requirements;
d)   system performance requirements;
e)   evaluation of the type-approval test results;
f)   evaluation of the uncertainty of the measurement results of the automated continuous measurement systems for particulate matter based on the type-approval test results.
Clauses 8 to 11 are aimed at monitoring networks performing the practical measurements of particulate matter in ambient air. These clauses contain information about:
g)   initial installation of the system in the monitoring network and acceptance testing;
h)   ongoing quality assurance/quality control;
i)   on-going verification of suitability;
j)   treatment, validation and reporting of measurement results.

This European Standard gives guidance on the measurement of elemental carbon (EC) and organic carbon (OC) following the requirement for the networks of all EU member states to measure EC and OC in particulate matter from June 2010 at background sites according to the Council Directive 2008/50/EC on ambient air quality and cleaner air for Europe [1].
This European Standard describes the analytical procedures for determining EC and OC on quartz fibre filters as μg/cm2, and the subsequent calculation of concentrations as µg/m3. Sampling onto filters is to be done in accordance with EN 12341:2014 for PM2,5. The sampling process determines the size fraction of the particulate matter, the retention of semi-volatile material, and uptake/loss of volatile organic compounds on the filter at the time of sampling.
The same analysis method may also be used for smaller size fractions than PM2,5. Any possible additional artefacts for larger particles, e.g. pyrolysis or higher concentrations of carbonates, should be assessed.
The scope includes rural background, urban background, road side and industrial measurement sites, to allow the assessment of additional exposure of people in urban areas as stated in the objectives of the council directive and to achieve coherence in the European approach.
The applicable concentration range of the proposed method is limited by the optical correction and instrument applied in the analysis of EC and OC. This method was validated from 0,2 µg CEC/cm² and 1,8 µg COC/cm² to 38 µg CEC/cm² and 49 µg COC/cm² in the laboratory and to 16 µg CEC/cm² and 45 µg COC/cm² in the field.

This European Standard describes a standard method for determining the PM10 or PM2,5 mass 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 m3/h, over a nominal sampling period of 24 h. Measurement results are expressed in µg/m3, 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/m3 (i.e. the limit of detection of the standard measurement method expressed as its uncertainty) up to 150 µg/m3 for PM10 and 120 µg/m3 for PM2,5.
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/m3 when 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 PM10 or PM2,5. 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 m3/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 m3/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 m3/h sampler and the 68 m3/h sampler for PM10 in EN 12341:1998, and the 30 m3/h PM2,5 inlet 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 uncertainties (see Annex B).
Other sampling systems, as described in Annex B of this European Standard, can be used provided that a well justified additional allowance is made to their uncertainties as derived from equivalence tests.
NOTE 2   By evaluating existing data it has been shown that these samplers give results for PM10 and PM2,5 that are equivalent to those obtained by application of this European Standard. Results are shown in Annex B.
This European Standard also provides guidance for the selection and testing of filters with the aim of reducing the measurement uncertainty of the results obtained when applying this European Standard.