FprEN 12341

Ambient air - Standard gravimetric measurement method for the determination of the PM10 or PM2,5 mass concentration of suspended particulate matter

This European Standard describes a standard method for determining the PM10 or PM2,5 mass concentrations of suspendedparticulate 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 atambient conditions near the inlet at the time of sampling.
The range of application of this European Standard is for 24 h measurements from approximately 1 μg/m3 (i.e. the limit of detection ofthe standard measurement method expressed as its uncertainty) up to 150 μg/m3 for PM10 and 120 μg/m3 for PM2,5.
This European Standard describes procedures and gives requirements for the testing and use of so-called sequential samplers,equipped with a filter changer, suitable for extended stand-alone operation. Sequential samplers are commonly used throughout theEuropean Union for the measurement of concentrations in ambient air of PM10 or PM2,5. However, this European Standard does notexclude the use of single-filter samplers.
This European Standard represents an evolution of earlier European Standards (EN 12341:1998 and 2014, EN 14907:2005). Newequipment procured shall comply fully with this European Standard.
Older versions of these samplers, including those described in EN 12341:2014 Annex B, have a special status in terms of their use. These samplers can still be used for monitoring purposes and for ongoing quality control, provided that a well justified additionalallowance is made to their uncertainties
This European Standard also provides guidance for the selection and testing of filters with the aim of reducing the measurementuncertainty of the results obtained when applying this European Standard.

Außenluft - Gravimetrisches Standardmessverfahren für die Bestimmung der PM10- oder PM2,5- Massenkonzentration des Schwebstaubes

Dieses Dokument legt ein Standardverfahren zur Bestimmung der PM10- oder PM2,5-Massenkonzentration in der Außenluft durch Probenahme auf Filtern und deren Wägung mittels einer Waage fest.
Die Messungen werden mit Probenahmegeräten durchgeführt, bei denen die Probeneinlässe entsprechend den Festlegungen in Anhang A ausgeführt sind, und die mit einem Nennvolumenstrom von 2,3 m3/h über eine Nennprobenahmedauer von 24 h betrieben werden. Das Verfahren umfasst die Konzentrationsbestimmung spezifischer Partikelfraktionen in der Außenluft in Bereichen klassifiziert als ländliche Gebiete, städtischer Hintergrund, verkehrsbezogene Orte und Orte, die durch industrielle Quellen beeinflusst sind. Die Messergebnisse werden in μg/m3 angegeben, wobei das Luftvolumen das Volumen bei Umgebungsbedingungen in der Nähe des Probeneinlasses während der Probenahme darstellt.
Der Anwendungsbereich dieses Dokuments für 24 h-Messungen reicht von etwa 1 μg/m3 (d. h. der Nachweisgrenze des Standardmessverfahrens, ausgedrückt als deren Unsicherheit) bis zu 150 μg/m3 bei PM10 und 120 μg/m3 bei PM2,5.
ANMERKUNG 1 Obwohl dieses Dokument nicht für höhere Konzentrationen validiert ist, kann der Anwendungsbereich bei Verwendung von geeigneten Filtermaterialien kann durchaus auf Konzentrationen in der Luft von bis zu etwa 200 μg/m3 erweitert werden (siehe 5.1.5.2).
Dieses Dokument legt Verfahren für und Anforderungen an die Prüfung und Anwendung sogenannter sequentieller Probenahmeeinrichtungen fest, die mit einem Filterwechsler ausgestattet und für einen längeren autonomen Betrieb geeignet sind. Sequentielle Probenahmeeinrichtungen werden üblicherweise in der gesamten Europäischen Union zur Messung von Konzentrationen von PM10 oder PM2,5 in Luft eingesetzt. Dieses Dokument schließt den Einsatz von Einzelfiltergeräten jedoch nicht aus.
ANMERKUNG 2 Ältere Versionen von Probenahmegeräten, die früheren Versionen von EN 12341 [2 und 21] entsprechen, können weiterhin zur Bewertung der Gleichwertigkeit von Kandidatmethoden verwendet werden, wobei die in EN 16450 [5] und in [11] beschriebenen Verfahren anzuwenden sind. Sobald neuere Versionen der nach diesem Dokument geprüften Probenahmegeräte zur Verfügung stehen, sollten die älteren Referenzprobenahmegeräte für Gleichwertigkeitsnachweise nach EN 16450 und nach [11] nicht mehr verwendet werden. Typprüfungsberichte über gleichwertige Verfahren sind weiterhin gültig, wenn sie in Auftrag gegeben wurden, bevor die nach diesem Dokument getesteten eignungsgeprüften Referenzsammlern verfügbar waren.
Dieses Dokument gibt auch Hilfestellung für die Auswahl und Prüfung von Filtern mit dem Ziel der Verringerung der Messunsicherheit der Ergebnisse aus diesem Verfahren.

Air ambiant - Méthode normalisée de mesurage gravimétrique pour la détermination de la concentration massique MP10 ou MP2,5 de matière particulaire en suspension

Le présent document spécifie une méthode normalisée de détermination des concentrations massiques de MP10 ou MP2,5 de la matière particulaire en suspension dans l’air ambiant en prélevant la matière particulaire sur les filtres et en les pesant à l’aide d’une balance.
Les mesurages sont effectués avec des préleveurs dont les têtes de prélèvement sont conçues conformément aux spécifications de l’Annexe A, fonctionnant à un débit nominal de 2,3 m3/h, pendant une période de prélèvement nominale de 24 h. La méthode couvre la détermination des concentrations de fractions spécifiques de matière particulaire en suspension présente dans l’air ambiant dans les zones classées comme zones rurales, périurbaines, proches d’axes de circulation automobile et influencées par des sources industrielles. Les résultats de mesure sont exprimés en μg/m3, le volume d’air étant le volume dans les conditions ambiantes à proximité de la tête de prélèvement pendant le prélèvement.
La gamme d’application du présent document, pour des mesurages sur 24 h, se situe entre environ 1 μg/m3 (c’est-à-dire, la limite de détection de la méthode de mesure normalisée exprimée sous la forme de son incertitude) et 150 μg/m3 pour la MP10 et 120 μg/m3 pour la MP2,5.
NOTE 1 Bien que la présente Norme européenne ne soit pas validée pour des concentrations supérieures, sa gamme d’application peut parfaitement être élargie à des concentrations dans l’air ambiant pouvant atteindre environ 200 μg/m3 en cas d’utilisation de matériaux filtrants appropriés (voir 5.1.5.2).
Le présent document spécifie les modes opératoires et donne les exigences d’essai et d’utilisation des préleveurs dits séquentiels, équipés d’un passeur de filtres, adaptés pour un fonctionnement autonome prolongé. Les préleveurs séquentiels sont couramment utilisés dans toute l’Union européenne pour mesurer les concentrations dans l’air ambiant de MP10 ou MP2,5. Toutefois, le présent document n’exclut pas l’utilisation de préleveurs à filtre unique.
NOTE 2 Les anciens modèles de préleveurs, conformes aux versions antérieures de l’EN 12341 [2 et 21], peuvent encore être utilisés pour évaluer l’équivalence des méthodes candidates, à l’aide des modes opératoires décrits dans l’EN 16450 [5] et en [11]. Dès que des modèles plus récents de préleveurs soumis à essai dans le présent document seront disponibles, cesser d’utiliser les anciens préleveurs de référence mentionnés dans l’EN 16450 et en [11]. Les rapports sur les essais de type des méthodes équivalentes restent valides s’ils ont été demandés avant que les préleveurs de référence de type approuvé soumis à essai dans le présent document ne soient disponibles.
Le présent document fournit également des recommandations pour la sélection et l’analyse des filtres en vue de réduire l’incertitude de mesure des résultats obtenus lors de l’application du présent document.

Zunanji zrak - Standardna gravimetrijska metoda za določevanje masne koncentracije frakcije lebdečih delcev PM10 ali PM2,5

General Information

• Status: Not Published
• Publication Date: 20-Aug-2023
• ICS: 13.040.20 - Ambient atmospheres
• Technical Committee: CEN/TC 264 - Air quality
• Drafting Committee: CEN/TC 264/WG 15 - Ambient Air - Reference gravimetric measurement method and equivalence procedure for the determination of the PM 2,5 micronmillimeters mass fraction of suspended particulate matter.
• Current Stage: 6055 - CEN Ratification completed (DOR) - Publishing
• Start Date: 24-Apr-2023
• Due Date: 03-Jul-2023
• Completion Date: 24-Apr-2023
• Directive: 2008/50/EC - Directive 2008/50/EC of the European Parliament and of the Council of 21 May 2008 on ambient air quality and cleaner air for Europe
• Mandate: M/037 - Standardization mandate addressed to CEN/CENELEC/ETSI in the area of Character set technology (programme)
• Mandate: M/503 - Mandate to CEN, CENELEC and ETSI in support of the Implementation of the Ambient Air Quality Legislation
• Ref Project: kSIST FprEN 12341:2023 - Ambient air - Standard gravimetric measurement method for the determination of the PM10 or PM2,5 mass concentration of suspended particulate matter

Relations

• Revises: EN 12341:2014 - Ambient air - Standard gravimetric measurement method for the determination of the PM10 or PM2,5 mass concentration of suspended particulate matter
• Effective Date: 19-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 12341:2022
01-julij-2022
Zunanji zrak - Standardna gravimetrijska metoda za določevanje masne
koncentracije frakcije lebdečih delcev PM10 ali PM2,5

Ambient air - Standard gravimetric measurement method for the determination of the

PM10 or PM2,5 mass concentration of suspended particulate matter
Außenluft - Gravimetrisches Standardmessverfahren für die Bestimmung der PM10-
oder PM2,5- Massenkonzentration des Schwebstaubes

Air ambiant - Méthode normalisée de mesurage gravimétrique pour la détermination de

la concentration massique MP10 ou MP2,5 de matière particulaire en suspension
Ta slovenski standard je istoveten z: prEN 12341
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
oSIST prEN 12341:2022 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 12341:2022
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oSIST prEN 12341:2022
DRAFT
EUROPEAN STANDARD
prEN 12341
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2022
ICS 13.040.20 Will supersede EN 12341:2014
English Version
Ambient air - Standard gravimetric measurement method
for the determination of the PM10 or PM2,5 mass
concentration of suspended particulate matter

Air ambiant - Méthode normalisée de mesurage Außenluft - Gravimetrisches Standardmessverfahren

gravimétrique pour la détermination de la für die Bestimmung der PM10- oder PM2,5-

concentration massique MP10 ou MP2,5 de matière Massenkonzentration des Schwebstaubes

particulaire en suspension

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 264.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12341:2022 E

worldwide for CEN national Members.
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Contents Page

European foreword ............................................................................................................................................ 4

1 Scope .......................................................................................................................................................... 6

2 Normative references .......................................................................................................................... 6

3 Terms, definitions, symbols and abbreviations ........................................................................ 7

3.1 Terms and definitions ......................................................................................................................... 7

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

4.3 Evaluation of measurement uncertainty .................................................................................... 12

5 Equipment, facilities and testing ................................................................................................... 13

5.1 Sampling system components and programme for type testing ....................................... 13

5.1.1 General.................................................................................................................................................... 13

5.1.2 Sampler design .................................................................................................................................... 16

5.1.3 Standard inlet design ......................................................................................................................... 16

5.1.4 Connecting pipe work ....................................................................................................................... 17

5.1.5 Filter holder and filter ...................................................................................................................... 17

5.1.6 Flow control system ........................................................................................................................... 18

5.1.7 Temperature sensors ........................................................................................................................ 20

5.1.8 Ambient pressure sensor ................................................................................................................. 20

5.1.9 Sampling period .................................................................................................................................. 20

5.1.10 Leak tightness of the sampling system ....................................................................................... 20

5.1.11 Storage conditions .............................................................................................................................. 22

5.1.12 Recording of operational parameters ......................................................................................... 22

5.1.13 Effect of failure of mains power ..................................................................................................... 23

5.1.14 Effect of ending sampling early due to filter clogging ........................................................... 23

5.1.15 Firmware, software and manual versions ................................................................................. 23

5.2 Sampling system components and programme for type testing ....................................... 24

5.3 Field tests ............................................................................................................................................... 25

5.3.1 General.................................................................................................................................................... 25

5.3.2 Performance tests ............................................................................................................................... 25

5.4 Type testing report ............................................................................................................................. 26

6 Filter conditioning, sampling, weighing facilities and weighing procedures ............... 27

6.1 General.................................................................................................................................................... 27

6.2 Weighing Facilities ............................................................................................................................. 28

6.2.1 Weighing room .................................................................................................................................... 28

6.2.2 Balance ................................................................................................................................................... 28

6.3 Filter conditioning and weighing prior to sampling .............................................................. 28

6.4 Sampling procedure ........................................................................................................................... 29

6.4.1 Filter cassette loading ....................................................................................................................... 29

6.4.2 Filter sampling ..................................................................................................................................... 29

6.4.3 Sample storage and transport procedures ................................................................................ 29

6.5 Filter conditioning and weighing after sampling .................................................................... 29

6.6 Weighing room procedures ............................................................................................................ 30

6.7 Filter blanks for ongoing quality control ................................................................................... 30

6.7.1 General.................................................................................................................................................... 30

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6.7.2 Weighing room blanks ...................................................................................................................... 30

6.7.3 Field blanks ........................................................................................................................................... 31

7 Ongoing quality control .................................................................................................................... 31

7.1 General ................................................................................................................................................... 31

7.2 Frequency of calibrations, checks and maintenance ............................................................. 31

7.3 Recording of operational parameters ......................................................................................... 33

7.4 Maintenance of the sampling system .......................................................................................... 33

7.5 Checks of sampler sensors .............................................................................................................. 33

7.6 Calibration of sampler sensors ...................................................................................................... 34

7.7 Checks of the sampler flow rate .................................................................................................... 34

7.8 Calibration of the sampler flow rate ............................................................................................ 34

7.9 Leak check of the sampling system .............................................................................................. 34

7.10 Checks of weighing facility sensors .............................................................................................. 34

7.11 Calibration of weighing facility sensors ..................................................................................... 35

7.12 Balance ................................................................................................................................................... 35

7.13 Check of the accuracy of sampler clock ...................................................................................... 35

8 Expression of results ......................................................................................................................... 35

9 Performance characteristics of the method ............................................................................. 35

9.1 General ................................................................................................................................................... 35

9.2 GUM concept ......................................................................................................................................... 36

9.3 Individual uncertainty sources ..................................................................................................... 37

9.3.1 General ................................................................................................................................................... 37

9.3.2 Collected particulate mass .............................................................................................................. 37

9.3.3 Time (t) ................................................................................................................................................... 40

9.3.4 Uncertainty budget ............................................................................................................................ 40

9.4 Expanded uncertainty vs. EU Data Quality Objectives .......................................................... 42

Bibliography ....................................................................................................................................................... 60

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European foreword

This document (prEN 12341:2022) has been prepared by Technical Committee CEN/TC 264 “Air

quality”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12341:2014.

Technical modifications which have been made in comparison with the previous edition are summarized

in Annex I.

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 EU Directive(s).

For relationship with EU Directive(s) see the introduction.
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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 document is to present a

harmonized methodology for monitoring the mass concentrations of suspended particulate matter (PM

and PM respectively) in ambient air, following Directive 2008/50/EC on ambient air quality and

2,5

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 document may also be used for measurement of mass

concentrations of other PM fractions such as PM . However, this document does not describe standardized sampling

inlets for such fractions.

The European Standard method described in this document is focused 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 reference materials currently available to provide traceability for PM or PM

10 2,5

measurements in ambient air. 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 document contains:

— a description of a manual gravimetric standard measurement method for PM or PM using

10 2,5
sequential samplers or single-filter samplers;

— a summary of performance requirements of the method, together with associated type testing

requirements for the sampler;

— 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 document method;

— 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 document were partly determined

in different comparative and validation trials. The trials were sponsored by the European Commission

and the European Free Trade Association.

The requirements of this document are targeted firstly towards obtaining optimum results for the

measurement of mass concentrations of PM or PM .
10 2,5
or PM

However, the filters collected for the purpose of determining the mass concentrations of PM10 2,5

can 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], as amended by Directive 2015/1480/EU [26].

— constituents of PM2,5 (see EN 16909 [9] and EN 16913 [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).
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1 Scope

This document describes a standard method for determining the PM or PM mass concentrations of

10 2,5

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 /h, over a nominal sampling period of 24 h. Measurement results are

expressed in µg/m , 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 document is for 24 h measurements from approximately 1 µg/m (i.e. the

limit of detection of the standard measurement method expressed as its uncertainty) up to 150 µg/m

for PM and 120 µg/m for PM .
10 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 when using suitable filter materials (see

5.1.5.2).

This document describes procedures and gives requirements for the testing and 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 or PM . However, this document does not exclude the use of single-

10 2,5
filter samplers.

NOTE 2 Older versions of samplers, which conform to previous versions of EN 12341, can still be used to evaluate

equivalence of candidate methods, using the procedures described in EN 16450 and in [11]. As newer versions of

samplers tested under this document become available, discontinue the use of older reference samplers in EN

16450 and in [11]. Type testing reports of equivalent methods are still valid if they were commissioned prior to the

availability of reference methods tested under this document.

This document 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 document.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

JCGM 100, Evaluation of measurement data — Guide to the expression of uncertainty in measurement

EN 15267-1:2009, Air quality - Certification of automated measuring systems - Part 1: General principles

EN 15267-2:2009, Air quality - Certification of automated measuring systems - Part 2: Initial assessment of

the AMS manufacturer’s quality management system and post certification surveillance for the

manufacturing process
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3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
ambient air

outdoor air in the troposphere, excluding workplaces where provisions concerning health and safety at

work apply and to which members of the public do not have regular access
[SOURCE: Directive 2008/50/EC]
3.1.2
calibration

operation that, under specified conditions, in a first step, establishes a relation between the quantity

values with measurement uncertainties provided by measurement standards and corresponding

indications with associated measurement uncertainties and, in a second step, uses this information to

establish a relation for obtaining a measurement result from an indication
[SOURCE: JCGM 200 [13]]
3.1.3
combined standard uncertainty

standard uncertainty of the result of a measurement when that result is obtained from the values of a

number of other quantities, equal to the positive square root of a sum of terms, the terms being the

variances or covariances of these other quantities weighted according to how the measurement result

varies with changes in these quantities
[SOURCE: JCGM 100]
3.1.4
competent authority

organization which implements the requirements of EU Directives and regulates installations, which

complies with the requirements of applicable European Standards

Note 1 to entry: In ambient air quality monitoring this is an authority that performs one or more of the tasks listed

in Article 3 of Directive 2008/50/EC.
3.1.5
competent body

organization which can demonstrate its competence for a specific task to the competent authority in the

Member State
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3.1.6
coverage factor

numerical factor used as a multiplier of the combined standard uncertainty in order to obtain an

expanded uncertainty
[SOURCE: JCGM 100]
3.1.7
expanded uncertainty

quantity defining an interval about the result of a measurement that may be expected to encompass a

large fraction of the distribution of values that could reasonably be attributed to the measurand

Note 1 to entry: The fraction may be viewed as the coverage probability or level of confidence of the interval.

Note 2 to entry: To associate a specific level of confidence with the interval defined by the expanded uncertainty

requires explicit or implicit assumptions regarding the probability distribution characterized by the measurement

result and its combined standard uncertainty. The level of confidence that may be attributed to this interval can be

known only to the extent to which such assumptions may be justified.
[SOURCE: JCGM 100]
3.1.8
field blank

filter that undergoes the same procedures of conditioning and weighing as a sample filter, including

transport to and from, and storage in the field, but is not used for sampling air

Note 1 to entry: A field blank is sometimes also called a procedure blank.
3.1.9
limit value

level fixed on the basis of scientific knowledge, with the aim of avoiding, preventing or reducing harmful

effects on human health and/or the environment as a whole, to be attained within a given period and not

to be exceeded once attained
[SOURCE: 2008/50/EC]
3.1.10
monitoring station

enclosure located in the field in which a sampler has been installed to measure particulate matter in such

a way that its performance and operation comply with the prescribed requirements
3.1.11
parallel measurement

measurements from measuring systems, sampling from the same air over the same time period

3.1.12
performance characteristic
one of the parameters assigned to a sampler in order to define its performance
3.1.13
performance criterion

limiting quantitative numerical value assigned to a performance characteristic, to which conformance is

tested
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3.1.14
period of unattended operation

time period over which the sampler can be operated without requiring operator intervention

3.1.15

particulate matter suspended in air which is small enough to pass through a size-selective inlet with a

50 % efficiency cut-off at x µm aerodynamic diameter

Note 1 to entry: By convention, the size-selective standard inlet designs prescribed in this document – used at the

prescribed flow rates – possess the required characteristics to sample the relevant PM fraction suspended in

ambient air.

Note 2 to entry: The efficiency of the size selectiveness of other inlets used may have a significant effect on the

fraction of PM surrounding the cut-off, and, consequently on the mass concentration of PMx determined.

3.1.16
reference method

measurement method(ology) which, by convention, gives the accepted reference value of the measurand

3.1.17
reference sampler

sampling system which has been proved to be compliant to the requirements of the design and

performance characteristics of this document
3.1.18
sampled air
ambient air that has been sampled through the sampling inlet and sampling system
3.1.19
sampling inlet

entrance to the sampling system where ambient air is collected from the atmosphere

3.1.20
standard uncertainty
uncertainty of the result of a measurement expressed as a standard deviation
[SOURCE: JCGM 100]
3.1.21
suspended particulate matter
SPM
notion of all particles surrounded by air in a given, undisturbed volume of air
3.1.22
time coverage

percentage of the reference period of the relevant limit value for which valid data for aggregation have

been collected
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3.1.23
type testing

examination of two or more samplers of the same model (identical in hardware and firmware) which are

submitted by a manufacturer to a competent body for testing of performance requirements

3.1.24
uncertainty (of measurement)

parameter associated with the result of a measurement that characterizes the dispersion of the values

that could reasonably be attributed to the measurand
[SOURCE: JCGM 100]
3.1.25
weighing room blank

filter that undergoes the same procedures of conditioning and weighing as a sample filter, but is stored

in the weighing room
3.2 Symbols and abbreviations

For the purposes of this document, the following symbols and abbreviated terms apply.

— φ Flow rate related to standard conditions
— φ Flow rate related to ambient conditions (T , P )
a a a
— ∆P Pressure difference determined for the time interval ∆t (leak test)
— ∆t Time interval needed for the pressure rise (leak test)
— C Concentration of PM (µg/m ) at ambient conditions
— d day(s)
— h hour(s)
— k Coverage factor
— m Filter mass
— m Mass of blank conditioned filter
— m Mass of sampled filter
— m Mass of sampled and conditioned filter
— m Mass of unsampled filter
— min Minutes
— P Pressure at t = 0 (leak test)
— P Ambient pressure
— t Sampling time
Ambient temperature
— Ta
— u Standard uncertainty
— u Between-sampler uncertainty
— u Uncertainty of flow
— u Uncertainty due to the effect of humidity on a blank filter
mfb
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— u Uncertainty due to hysteresis effects on mass of PM
— u Uncertainty of the mass of PM (ml – mu)
— u Uncertainty due to buoyancy
— u Uncertainty due to balance calibration
mba
— u Uncertainty due to contamination
— u Uncertainty due to lack of filter efficiency
mfe
— u Uncertainty due to the interaction with gases
— u Uncertainty due to the effect of humidity on particulate matter
mhp
— umip Uncertainty due to inlet performance
— u Uncertainty of the mass of a sampled filter
— u Uncertainty due to static charging of the filter
— u Uncertainty due to losses of PM on transport and storage
mtl
— u Uncertainty of the mass of an unsampled filter
— u Uncertainty due to balance zero drift
mzd
— φ Leak flow rate (leak test)
— V Estimated total volume of the system (dead volume)
sys
— w Relative uncertainty
— W
...