SIST EN 14211:2025
(Main)Ambient air - Standard method for the measurement of the concentration of nitrogen dioxide and nitrogen monoxide by chemiluminescence
Ambient air - Standard method for the measurement of the concentration of nitrogen dioxide and nitrogen monoxide by chemiluminescence
This document specifies a continuous measurement method for the determination of the concentrations of nitrogen dioxide and nitrogen monoxide present in ambient air based on the chemiluminescence measuring principle. This document describes the performance characteristics and sets the relevant minimum criteria required to select an appropriate chemiluminescence analyser by means of type testing. It also includes the evaluation of the suitability of an analyser for use in a specific fixed site so as to meet the data quality requirements as specified in Annex I of Directive 2008/50/EC [1] and requirements during sampling, calibration and quality assurance for use.
The method is applicable to the determination of the concentration of nitrogen dioxide present in ambient air up to 500 µg/m3. This concentration range represents the certification range for nitrogen dioxide for type testing.
The method is applicable to the determination of the concentration of nitrogen monoxide present in ambient air up to 1 200 µg/m3. This concentration range represents the certification range for nitrogen monoxide for the type testing.
NOTE 1 It is possible to use other ranges depending on the levels present in ambient air.
NOTE 2 When this document is used for purposes other than for measurements required by Directive2008/50/EC, the ranges and uncertainty requirements possibly do not apply.
The method covers the determination of ambient air concentrations of nitrogen dioxide and nitrogen monoxide in zones classified as rural areas, urban-background areas, traffic-orientated locations and locations influenced by industrial sources.
The results are expressed in µg/m3 (at 20 °C and 101,3 kPa).
NOTE 3 500 µg/m3 of nitrogen dioxide corresponds to 261 nmol/mol of nitrogen dioxide at 20 °C and 101,3 kPa. 1 200 µg/m3 of nitrogen monoxide corresponds to 962 nmol/mol of nitrogen monoxide at 20 °C and 101,3 kPa.
This document contains information for different groups of users.
Clause 5 to Clause 7 and Annex B and Annex C contain general information about the principles of NOx measurement by chemiluminescence analyser and sampling equipment.
Clause 8 and Annex E are specifically directed towards test houses and laboratories that perform type testing of NOx analysers. These sections contain information about:
— type testing conditions, test procedures and test requirements;
— analyser performance requirements;
— evaluation of the type testing results;
— evaluation of the uncertainty of the measurement results of the NOx analyser based on the type testing results.
Clause 9 to Clause 11 and Annex F and Annex G are directed towards monitoring networks performing the practical measurements of NOx in ambient air. These sections contain information about:
— initial installation of the analyser in the monitoring network and acceptance testing;
— ongoing quality assurance/quality control;
— calculation and reporting of measurement results;
— evaluation of the uncertainty of measurement results under practical monitoring conditions.
This document represents an evolution of earlier editions (EN 14211:2005 and EN 14211:2012). It is advisable that when equipment is procured it complies fully with this document.
NOTE 4 Type testing performed prior to the publication of this document for the purpose of demonstrating equivalence are still valid.
NOTE 5 Analysers type tested prior to the publication of this document remain valid for use for regulated monitoring purposes.
Außenluft - Messverfahren zur Bestimmung der Konzentration von Stickstoffdioxid und Stickstoffmonoxid mit Chemilumineszenz
Dieses Dokument legt ein kontinuierliches Chemilumineszenz-Messverfahren zur Bestimmung der Konzentration von Stickstoffdioxid und Stickstoffmonoxid in Luft fest. Es nennt die Leistungskenngrößen und legt die Mindestanforderungen für die Eignungsprüfung von Chemilumineszenz-Messgeräten fest. Es beinhaltet auch die Bewertung der Eignung eines Messgeräts für den Einsatz an einem bestimmten ortsfesten Messstandort bezüglich der Anforderungen an die Datenqualität nach Anhang I der Richtlinie 2008/50/EG [1] und bezüglich der Anforderungen für Probennahme, Kalibrierung und Qualitätssicherung.
Das Verfahren ist anwendbar zur Bestimmung der Massenkonzentration von Stickstoffdioxid in Außenluft bis 500 µg/m3. Dieser Konzentrationsbereich entspricht dem Zertifizierungsbereich für Stickstoffdioxid für die Eignungsprüfung.
Das Verfahren ist anwendbar zur Bestimmung der Massenkonzentration von Stickstoffmonoxid in Außenluft bis 1 200 µg/m3. Dieser Konzentrationsbereich entspricht dem Zertifizierungsbereich für Stickstoffmonoxid für die Eignungsprüfung.
ANMERKUNG 1 Je nach Konzentrationsniveau in der Luft können auch andere Bereiche gewählt werden.
ANMERKUNG 2 Wird dieses Dokument für andere Zwecke als für Messungen nach Richtlinie 2008/50/EG eingesetzt, dann brauchen die Anforderungen hinsichtlich Anwendungsbereich und Unsicherheit nicht zur Geltung kommen.
Das Verfahren umfasst die Bestimmung der Konzentration von Stickstoffdioxid und Stickstoffmonoxid an Standorten, die als ländlich, städtischer Hintergrund, verkehrsbezogen und durch industrielle Quellen beeinflusst klassifiziert sind.
Die Ergebnisse werden in µg/m3 (bei 20 C und 101,3 kPa) angegeben.
ANMERKUNG 3 500 µg/m3 Stickstoffdioxid entsprechen 261 nmol/mol Stickstoffdioxid bei 20 C und 101,3 kPa. 1 200 µg/m3 Stickstoffmonoxid entsprechen 962 nmol/mol Stickstoffmonoxid bei 20 C und 101,3 kPa.
Dieses Dokument enthält Informationen für verschiedene Nutzergruppen.
Abschnitt 5 bis Abschnitt 7 und Anhang B und Anhang C enthalten allgemeine Informationen über die Grundlagen der NOx-Messung mit einem Chemilumineszenz-Messgerät sowie über die Probennahmeeinrichtung.
Abschnitt 8 und Anhang E richten sich speziell an Prüfinstitute und -laboratorien, die Eignungsprüfungen von NOx-Messgeräten durchführen. Diese Abschnitte enthalten Informationen über:
— Prüfbedingungen, -verfahren und -anforderungen bei der Eignungsprüfung;
— Anforderungen an die Leistungsfähigkeit des Messgeräts;
— die Bewertung der Ergebnisse der Eignungsprüfung;
— die Bewertung der Unsicherheit der Messergebnisse des NOx-Messgeräts anhand der Eignungsprüfungsergebnisse.
Abschnitt 9 bis Abschnitt 11 und Anhang F und Anhang G richten sich an die Betreiber von Messnetzen, mit denen NOx-Messungen in Luft durchgeführt werden. Diese Abschnitte enthalten Informationen über:
— die Erstinstallation des Messgeräts im Messnetz und Eignungsbewertung;
— die laufende Qualitätssicherung und -kontrolle;
— die Berechnung und Übermittlung der Messergebnisse;
— die Bewertung der Unsicherheit der Messergebnisse unter Messbedingungen.
Das vorliegende Dokument stellt eine Weiterentwicklung der vorangegangenen Ausgaben (EN 14211:2005 und EN 14211:2012) dar. Es wird empfohlen, dass bei der Beschaffung von Geräten diese vollständig mit diesem Dokument übereinstimmen.
ANMERKUNG 4 Eignungsprüfungen, die vor der Veröffentlichung dieses Dokuments zum Zweck des Nachweises der Gleichwertigkeit durchgeführt wurden, sind weiterhin gültig.
ANMERKUNG 5 Eignungsprüfungen von Messgeräten, die vor der Veröffentlichung dieses Dokuments durchgeführt wurden, bleiben weiterhin für die Verwendung für regulierte Beobachtungszwecke gültig.
Air ambiant - Méthode normalisée pour le mesurage de la concentration en dioxyde d'azote et monoxyde d'azote par chimiluminescence
Le présent document spécifie une méthode de mesure en continu pour la détermination des concentrations en dioxyde d’azote et en monoxyde d’azote dans l’air ambiant, selon le principe de mesure par chimiluminescence. Le présent document décrit les caractéristiques de performance et fixe les critères minimaux requis pour sélectionner un analyseur par chimiluminescence approprié à l’aide d’essais de type. Il présente également l’évaluation de l’aptitude d’un analyseur sur un site fixe spécifique de manière à répondre aux exigences de qualité des données spécifiées à l’Annexe I de la Directive 2008/50/CE [1] ainsi qu’aux exigences à observer au cours du prélèvement, de l’étalonnage et de l’assurance qualité.
La méthode s’applique à la détermination de la concentration en dioxyde d’azote présent dans l’air ambiant jusqu’à 500 µg/m3. Cette plage de concentration représente l’étendue de mesure certifiée en dioxyde d’azote pour les essais de type.
La méthode s’applique à la détermination de la concentration en monoxyde d’azote présent dans l’air ambiant jusqu’à 1 200 µg/m3. Cette plage de concentration représente l’étendue de mesure certifiée en monoxyde d’azote pour les essais de type.
NOTE 1 D’autres plages peuvent être utilisées selon les niveaux présents dans l’air ambiant.
NOTE 2 Lorsque le présent document est utilisé à d’autres fins que les mesurages requis par la Directive 2008/50/CE, les exigences relatives à la plage et à l’incertitude peuvent ne pas s’appliquer.
La méthode couvre la détermination des concentrations en dioxyde d’azote et en monoxyde d’azote présents dans l’air ambiant dans les zones classées comme zones rurales, urbaines de fond, proches d’axes de circulation automobile et influencées par des sources industrielles.
Les résultats sont exprimés en µg/m3 (à 20 °C et 101,3 kPa).
NOTE 3 500 µg/m3 de dioxyde d’azote correspondent à 261 nmol/mol de dioxyde d’azote à 20 °C et 101,3 kPa. 1 200 µg/m3 de monoxyde d’azote correspondent à 962 nmol/mol de monoxyde d’azote à 20 °C et 101,3 kPa.
Le présent document contient des informations pour différents groupes d’utilisateurs.
Les Articles 5 à 7 et les Annexes B et C contiennent des informations générales relatives aux principes de mesure des NOx à l’aide d’un analyseur par chimiluminescence et d’un équipement de prélèvement.
L’Article 8 et l’Annexe E concernent tout particulièrement les organismes et les laboratoires d’essai qui effectuent des essais de type des analyseurs de NOx. Ces sections contiennent des informations concernant :
les conditions des essais de type, les modes opératoires d’essai et les exigences d’essai ;
les exigences de performance de l’analyseur ;
l’évaluation des résultats des essais de type ;
l’évaluation de l’incertitude des résultats de mesure de l’analyseur de NOx d’après les résultats des essais de type.
Les Articles 9 à 11 et les Annexes F et G concernent les réseaux de surveillance effectuant les mesurages en conditions réelles des NOx dans l’air ambiant. Ces sections contiennent des informations concernant :
l’installation initiale de l’analyseur dans le réseau de surveillance et l’essai de réception ;
l’assurance qualité / le contrôle qualité en continu ;
le calcul et le compte-rendu des résultats de mesure ;
l’évaluation de l’incertitude des résultats de mesure sous des conditions de surveillance réelles.
Le présent document représente une évolution par rapport aux éditions antérieures (EN 14211:2005 et EN 14211:2012). Il est conseillé que l’équipement acheté soit parfaitement conforme au présent document.
[...]
Zunanji zrak - Standardna metoda za določanje koncentracije dušikovega dioksida in dušikovega monoksida s kemiluminiscenco
Ta dokument določa metodo stalnega merjenja za določitev koncentracij dušikovega dioksida in dušikovega monoksida v zunanjem zraku na podlagi kemoluminiscenčnega merilnega principa. Ta dokument opisuje lastnosti delovanja in vzpostavlja ustrezna minimalna merila, ki so potrebna za izbiro primernega kemoluminiscenčnega analizatorja s tipskimi preskusi. Vključuje tudi oceno ustreznosti analizatorja za uporabo na specifičnem fiksnem mestu, da se izpolnijo zahteve o kakovosti podatkov (za več informacij glej dodatek I Direktive 2008/50/ES [1]) ter zahteve med vzorčenjem, kalibriranjem in zagotavljanjem kakovosti za uporabo.
Metoda se uporablja za določitev koncentracije dušikovega dioksida v zunanjem zraku do vrednosti 500 μg/m3. Te koncentracije predstavljajo razpon certificiranja za dušikov dioksid za tipske preskuse.
Metoda se uporablja za določitev koncentracije dušikovega monoksida v zunanjem zraku do vrednosti 1200 µg/m3. Te koncentracije predstavljajo razpon certificiranja za dušikov monoksid za tipske preskuse.
OPOMBA 1: Uporabiti je mogoče tudi druge koncentracije, odvisno od ravni v zunanjem zraku.
OPOMBA 2: Primeri izračunov proračuna negotovosti so podani v dodatkih od F do H v zvezi z Direktivo 2008/50/ES [1]. V primeru posodobitev mejnih vrednosti v prihodnjih različicah Direktive 2008/50/ES [1] lahko uporabnik te nove vrednosti uporabi za izračun merilne negotovosti.
Ta metoda zajema določitev koncentracij dušikovega dioksida in dušikovega monoksida v zunanjem zraku na področjih, ki so uvrščena med podeželska območja, območja v urbanem okolju, prometna območja in lokacije, na katere vplivajo industrijski viri.
Rezultati so izraženi v μg/m3 (pri 20 °C in 101,3 kPa).
OPOMBA 3: 500 µg/m3 dušikovega dioksida ustreza 261 nmol/mol dušikovega dioksida pri 20 °C in 101,3 kPa.
1200 µg/m3 dušikovega dioksida ustreza 962 nmol/mol dušikovega dioksida pri 20 °C in 101,3 kPa.
Ta dokument vsebuje informacije za različne skupine uporabnikov.
Točke od 5 do 7 ter dodatka B in C vsebujejo splošne informacije o načelih merjenja dušikovih oksidov (NOx) s kemoluminiscenčnimi analizatorji in opremo za vzorčenje.
Osrednji predmet obravnave v točki 8 in dodatku E so laboratoriji, ki izvajajo tipske preskuse analizatorjev dušikovih oksidov. Ti razdelki vsebujejo informacije o:
– pogojih tipskih preskusov ter preskusnih postopkih in zahtevah;
– zahtevah glede učinkovitosti analizatorja;
– ocenah rezultatov tipskih preskusov;
– oceni povezane negotovosti meritev analizatorja dušikovih oksidov na podlagi rezultatov tipskih preskusov.
Osrednji predmet obravnave v točkah od 9 do 11 ter dodatkih F in G so mreže za spremljanje, ki izvajajo praktične meritve dušikovih oksidov v zunanjem zraku. Ti razdelki vsebujejo informacije o:
– začetni namestitvi analizatorja v mreži za spremljanje in preskušanju sprejemljivosti;
– stalnem zagotavljanju oziroma nadzoru kakovosti;
– izračunavanju in sporočanju rezultatov merjenja;
– oceni povezane negotovosti meritev v okviru pogojev praktičnega spremljanja.
Ta dokument je nadgradnja prejšnjih različic (EN 14211:2005 in EN 14211:2012).
OPOMBA 4: Analizatorje, ki so bili tipsko preskušeni pred objavo tega dokumenta, je mogoče še vedno uporabljati za regulirano spremljanje. S pojavom novejših različic analizatorjev, preskušenih v skladu s tem dokumentom, se uporaba starejših referenčnih analizatorjev preneha.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-april-2025
Nadomešča:
SIST EN 14211:2012
Zunanji zrak - Standardna metoda za določanje koncentracije dušikovega dioksida
in dušikovega monoksida s kemiluminiscenco
Ambient air - Standard method for the measurement of the concentration of nitrogen
dioxide and nitrogen monoxide by chemiluminescence
Außenluft - Messverfahren zur Bestimmung der Konzentration von Stickstoffdioxid und
Stickstoffmonoxid mit Chemilumineszenz
Air ambiant - Méthode normalisée pour le mesurage de la concentration en dioxyde
d'azote et monoxyde d'azote par chimiluminescence
Ta slovenski standard je istoveten z: EN 14211:2024
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN 14211
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2024
EUROPÄISCHE NORM
ICS 13.040.20 Supersedes EN 14211:2012
English Version
Ambient air - Standard method for the measurement of the
concentration of nitrogen dioxide and nitrogen monoxide
by chemiluminescence
Air ambiant - Méthode normalisée pour le mesurage de Außenluft - Messverfahren zur Bestimmung der
la concentration en dioxyde d'azote et monoxyde Konzentration von Stickstoffdioxid und
d'azote par chimiluminescence Stickstoffmonoxid mit Chemilumineszenz
This European Standard was approved by CEN on 11 November 2024.
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, 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, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14211:2024 E
worldwide for CEN national Members.
Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 7
4 Abbreviated terms . 12
5 Principle . 13
5.1 General . 13
5.2 Measuring principle . 13
5.3 Type testing . 14
5.4 Field operation and quality control. 14
6 Sampling . 14
6.1 General . 14
6.2 Sampling location . 15
6.3 Sampling system . 15
6.4 Control and regulation of sample flow rate . 17
6.5 Sampling pump for the manifold . 17
7 Analyser equipment . 17
7.1 General . 17
7.2 Converter . 17
7.3 Ozone generator . 18
7.4 Reaction chamber . 18
7.5 Optical filter . 18
7.6 Detector . 18
7.7 Ozone removal device . 18
7.8 Sampling pump for the analyser . 18
7.9 Particle filter . 18
8 Type testing of nitrogen dioxide and nitrogen monoxide analysers. 19
8.1 General . 19
8.2 Relevant performance characteristics and performance criteria. 20
8.3 Design change . 23
8.4 Procedures for determination of the performance characteristics during the
laboratory test . 23
8.5 Determination of the performance characteristics during the field test. 37
8.6 Type testing and uncertainty calculation . 41
9 Field operation and ongoing quality control . 41
9.1 General . 41
9.2 Suitability evaluation . 42
9.3 Initial installation . 44
9.4 Ongoing quality assurance/quality control . 45
9.5 Calibration of the analyser . 48
9.6 Checks . 50
9.7 Maintenance . 56
9.8 Data handling and data reports . 57
9.9 Measurement uncertainty . 58
10 Expression of results . 58
11 Test reports and documentation . 59
11.1 Type testing . 59
11.2 Field operation . 60
Annex A (normative) Test of lack of fit . 62
A.1 Establishment of the regression line . 62
A.2 Calculation of the residuals of the averages . 62
Annex B (informative) Sampling equipment . 64
Annex C (informative) Types of chemiluminescence analysers . 66
Annex D (informative) Manifold testing . 69
D.1 Procedure for applying test gas . 69
D.2 Procedure for the cross test . 70
Annex E (normative) Type testing . 73
E.1 Type testing and uncertainty calculation . 73
E.2 Type testing Requirement a) . 73
E.3 Type testing Requirement b). 75
E.4 Type testing Requirement c) . 88
E.5 Type testing Requirement d). 88
Annex F (informative) Calculation of uncertainty in field operation at the hourly limit value . 95
F.1 General . 95
F.2 Combined standard uncertainty . 95
F.3 Standard uncertainties . 96
F.4 Example calculation . 103
Annex G (informative) Calculation of uncertainty in field operation at the annual limit
value . 105
G.1 General . 105
Annex H (informative) Test stand for the test point “sensitivity coefficient of sample gas
pressure" . 118
Annex I (informative) Significant technical changes . 119
Bibliography . 120
European foreword
This document (EN 14211:2024) 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 June 2025, and conflicting national standards shall be
withdrawn at the latest by June 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 14211:2012.
The technical modifications in comparison with the previous edition are listed in Annex H
of this document.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: 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, Türkiye and the United
Kingdom.
1 Scope
This document specifies a continuous measurement method for the determination of the concentrations
of nitrogen dioxide and nitrogen monoxide present in ambient air based on the chemiluminescence
measuring principle. This document describes the performance characteristics and sets the relevant
minimum criteria required to select an appropriate chemiluminescence analyser by means of type
testing. It also includes the evaluation of the suitability of an analyser for use in a specific fixed site
so as to meet the data quality requirements (see Annex I of Directive 2008/50/EC [1] for additional
information) and requirements during sampling, calibration and quality assurance for use.
The method is applicable to the determination of the concentration of nitrogen dioxide present
in ambient air up to 500 µg/m . This concentration range represents the certification range for nitrogen
dioxide for type testing.
The method is applicable to the determination of the concentration of nitrogen monoxide present
in ambient air up to 1 200 µg/m . This concentration range represents the certification range for nitrogen
monoxide for the type testing.
NOTE 1 It is possible to use other ranges depending on the levels present in ambient air.
NOTE 2 Exemplar uncertainty budget calculations are given in Annexes F to H referring to Directive 2008/50/EC
[1]. In the event that the Limit Values are updated in future iterations of Directive 2008/50/EC [1], the user can use
these new values to calculate measurement uncertainties.
The method covers the determination of ambient air concentrations of nitrogen dioxide and nitrogen
monoxide in zones classified as rural areas, urban-background areas, traffic-orientated locations
and locations influenced by industrial sources.
The results are expressed in µg/m (at 20 °C and 101,3 kPa).
NOTE 3 500 µg/m of nitrogen dioxide corresponds to 261 nmol/mol of nitrogen dioxide at 20 °C and 101,3 kPa.
1 200 µg/m of nitrogen monoxide corresponds to 962 nmol/mol of nitrogen monoxide at 20 °C and 101,3 kPa.
This document contains information for different groups of users.
Clause 5 to Clause 7 and Annex B and Annex C contain general information about the principles of NO
x
measurement by chemiluminescence analyser and sampling equipment.
Clause 8, Annex E is specifically directed towards test houses and laboratories that perform type testing
of NO analysers. These sections contain information about:
x
— type testing conditions, test procedures and test requirements;
— analyser performance requirements;
— evaluation of the type testing results;
— evaluation of the associated uncertainty of the measurement performed by the NO analyser based
x
on the type testing results.
Clause 9 to Clause 11 and Annex F and Annex G are directed towards monitoring networks performing
the practical measurements of NO in ambient air. These sections contain information about:
x
— initial installation of the analyser in the monitoring network and acceptance testing;
— ongoing quality assurance/quality control;
— calculation and reporting of measurement results;
— evaluation of the associated uncertainty of the measurements under practical monitoring conditions.
This document represents an evolution of earlier editions (EN 14211:2005 and EN 14211:2012).
NOTE 4 Analysers type tested prior to the publication of this document can still be used for regulated monitoring
purposes. As newer versions of analysers tested under this document become available, discontinue the use of older
reference analysers.
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.
EN 15267-1, Air quality - Assessment of air quality monitoring equipment - Part 1: General principles of
certification
EN 15267-2, Air quality - Assessment of air quality monitoring equipment - Part 2: Initial assessment of the
manufacturer’s quality management system and post certification surveillance for the manufacturing
process
EN ISO 6142-1, Gas analysis — Preparation of calibration gas mixtures — Gravimetric method (ISO 6142-
1)
EN ISO 6143, Gas analysis - Comparison methods for determining and checking the composition of
calibration gas mixtures (ISO 6143)
EN ISO 6144, Gas analysis - Preparation of calibration gas mixtures - Static volumetric method (ISO 6144)
EN ISO 6145-6, Gas analysis - Preparation of calibration gas mixtures using dynamic methods - Part 6:
Critical flow orifices (ISO 6145-6)
EN ISO 6145-7, Gas analysis - Preparation of calibration gas mixtures using dynamic methods - Part 7:
Thermal mass-flow controllers (ISO 6145-7)
EN ISO 6145-10, Gas analysis - Preparation of calibration gas mixtures using dynamic volumetric methods
- Part 10: Permeation method (ISO 6145-10)
EN ISO 14956, Air quality - Evaluation of the suitability of a measurement procedure by comparison with a
required measurement uncertainty (ISO 14956)
ISO 19229, Gas analysis - Purity analysis and the treatment of purity data
3 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:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
adjustment of a measuring system
set of operations carried out on a measuring system so that it provides prescribed indications
corresponding to given values of a quantity to be measured
Note 1 to entry: Types of adjustment of a measuring system include zero adjustment of a measuring system,
offset adjustment, and span adjustment (sometimes called gain adjustment).
Note 2 to entry: Adjustment of a measuring system should not be confused with calibration, which is a
prerequisite for adjustment.
Note 3 to entry: In the context of this document, adjustment is generally performed on measurement data rather
than on the analyser.
[SOURCE: JCGM 200:2012, 3.11] [2]
3.2
ambient air
outdoor air in the troposphere where provisions concerning health and safety at work apply and to which
members of the public do not have regular access
Note 1 to entry: This excluding workplaces as defined by Directive 89/654/EEC.
[SOURCE: Council Directive 2008/50/EC] [1]
3.3
analyser
measuring system that provides an output signal which is a function of the concentration or partial
pressure of one or more components in a gas mixture and flow or temperature of this gas mixture
3.4
availability of the analyser
fraction of the time period for which valid measuring data of the ambient air concentration is available
from an analyser
3.5
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
Note 1 to entry: A calibration can be expressed by a statement, calibration function, calibration diagram,
calibration curve, or calibration table. In some cases, it can consist of an additive or multiplicative correction of the
indication with associated measurement uncertainty.
Note 2 to entry: Calibration should not be confused with adjustment of a measuring system, often mistakenly
called “self-calibration”, nor with verification of a calibration.
Note 3 to entry: Often, the first step alone in the above definition is perceived as being calibration.
Note 4 to entry: In the context of this document, calibration is a comparison of the analyser response to a known
gas concentration with a known uncertainty when the information obtained from the comparison is used
for the successive adjustment (if needed) of the analyser.
[SOURCE: JCGM 200:2012, 2.39] [2]
3.6
certification range
concentration range for which the analyser is type tested
3.7
check
verification that the analyser is still operating within specified performance limits
3.8
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 co-variances of these other quantities weighted according to how the measurement
result varies with changes in these quantities
[SOURCE: JCGM 100:2008, 2.3.4] [3]
3.9
converter efficiency
degree of conversion of nitrogen dioxide present in the sample gas into nitrogen monoxide, given as a
percentage
3.10
coverage factor
numerical factor used as a multiplier of the combined standard uncertainty in order to obtain
an expanded uncertainty
[SOURCE: JCGM 100:2008, 2.3.6] [3]
3.11
competent body
organization which can demonstrate its competence for a specific task to the national competent
authority of the Member State
3.12
detection limit
smallest concentration of a measurand that can be reliably detected by a specific measurement process
Note 1 to entry: The detection limit is calculated as 3,3 × (sr,z/B) where sr,z is the standard deviation of analyser
response at zero measurand concentration (see 8.4.5) and B is the slope of the calibration function [4].
3.13
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 can 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 can be attributed to this interval can be
known only to the extent to which such assumptions can be justified.
[SOURCE: JCGM 100:2008, 2.3.5] [3]
Note 3 to entry: For the purpose of this document, the expanded uncertainty is the combined standard
uncertainty multiplied by a coverage factor k = 2 resulting in an interval with a level of confidence of 95 %.
3.14
fall time
difference between the response time (fall) and the lag time (fall)
3.15
independent measurement
individual measurement that is not influenced by a previous individual measurement by separating
two individual measurements by at least four response times
Note 1 to entry: The largest value of response time (rise) and response time (fall) are intended.
3.16
individual measurement
measurement averaged over a time period equal to the response time of the analyser
Note 1 to entry: The largest value of response time (rise) and response time (fall) are intended.
Note 2 to entry: This definition differs from the meaning of the concept “individual measurement” in
Directive 2008/50/EC [1].
3.17
influence quantity
quantity that is not the measurand but that affects the result of the measurement
[SOURCE: JCGM 100:2008, B.2.10] [3]
3.18
interferent
component of the air sample, excluding the measured constituent, that affects the output signal
3.19
lack of fit
maximum deviation from the linear regression line of the average of a series of measurement results
at the same concentration
3.20
lag time
time interval from the moment at which a step change of sample concentration occurs at the inlet
of the analyser to the moment at which the output reading reaches a level corresponding to a predefined
change of the stable output reading
3.21
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: Council Directive 2008/50/EC] [1]
3.22
long-term drift
difference between zero or span readings over a determined period of time (e.g., period of unattended
operation)
3.23
monitoring station
enclosure located in the field in which an analyser has been installed to monitor concentrations of one
or more ambient air pollutants
3.24
parallel measurement
measurement from different analysers, sampling with the same sampling system, starting at the same
time and ending at the same time
Note 1 to entry: sampling can be performed from one and the same sampling manifold or with identical individual
sampling lines
3.25
performance characteristic
one of the parameters assigned to equipment in order to define its performance
3.26
performance criterion
limiting quantitative numerical value assigned to a performance characteristic, to which conformance
is tested
3.27
period of unattended operation
time period over which the drift complies with the performance criterion for long-term drift
3.28
repeatability of results of measurement
closeness of the agreement between the results of successive individual measurements of nitrogen
monoxide and nitrogen dioxide carried out under the same conditions of measurement
Note 1 to entry: These conditions include:
a) the same measurement procedure;
b) the same observer;
c) the same analyser, used under the same conditions;
d) at the same location;
e) repetition over a short period of time.
3.29
reproducibility under field conditions
closeness of the agreement between the results of simultaneous measurements with two analysers
in ambient air carried out under the same conditions of measurement
Note 1 to entry: These conditions are called field reproducibility conditions and include:
a) the same measurement procedure;
b) two identical analysers, used under the same conditions;
c) at the same monitoring station;
d) the period of unattended operation.
3.30
residence time inside the analyser
time period for the sampled air to be transported from the inlet of the analyser to the reaction chamber
for the NO-channel
3.31
residence time in the sampling system
time period for the sampled air to be transferred to the inlet of the analyser
3.32
response time
time interval from the instant at which a step change of sample concentration occurs at the inlet
of the analyser to the instant at which the output reading reaches a level corresponding to a predefined
change of the output reading
3.33
sampled air
part of ambient air that is transferred through the sampling inlet and sampling system for subsequent
measurement
3.34
sample gas temperature
temperature of the sampled gas at the sample inlet
Note 1 to entry: The term “gas” can refer to a test gas used in type testing or to ambient air transferred
to the analyser.
3.35
sampling system
the assembly of components needed to transfer ambient air to the analyser
3.36
short-term drift
difference between zero or span readings at the beginning and end of a 12 h period
3.37
standard uncertainty
uncertainty of the result of a measurement expressed as a standard deviation
[SOURCE: JCGM 100:2008, 2.3.1] [3]
3.38
surrounding temperature
temperature of the air directly surrounding the analyser
3.39
total residence time
sum of the residence time in the sampling system and the residence time inside the analyser
3.40
type testing
examination of two or more analysers of the same design which are submitted by a manufacturer to a
competent body including the tests necessary for approval of the design (determination of fitness
for purpose of a specific device model/of an unambiguous designated analyser)
Note 1 to entry: In EN 15267-1 and -2, type testing is referred to as performance testing.
3.41
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 100:2008, 2.2.3 [3]]
4 Abbreviated terms
AMS automated measuring system (sometimes referred to as continuous automated measuring
system (CAMS))
PFA perfluoro-alkoxy
PTFE Polytetrafluoroethylene
5 Principle
5.1 General
This document describes the method for measurement of the concentrations of nitrogen dioxide and
nitrogen monoxide in ambient air by means of chemiluminescence. The requirements, the specific
components of the chemiluminescence analyser and its sampling system are described. A number of
performance characteristics with associated minimum performance criteria are given for the analyser.
The actual values of these performance characteristics for a specific type of analyser shall be determined
in a so-called type test for which procedures have been described. The type testing comprises laboratory
tests and field tests. The selection of a type-tested analyser for a specific measuring task in the field is
based on the calculation of the expanded uncertainty of the measured values obtained by the
measurement method. In this expanded uncertainty calculation, the actual values of various performance
characteristics of a type tested analyser and the site-specific conditions at the monitoring station are
taken into account (see Table 8 and 9.9). The expanded uncertainty of the method shall not exceed the
limits (this is also specified in Annex I of Directive 2008/50/EC [1]). Requirements and
recommendations for quality assurance and quality control are given for the measurements in the field
(see 9.4).
5.2 Measuring principle
Chemiluminescence is based on the reaction of nitrogen monoxide with ozone. In a chemiluminescence
analyser, air is sampled through a filter (to prevent contamination of the gas conveying system, especially
the optical components of the analyser) and fed at a constant flow rate into the reaction chamber of the
analyser, where it is mixed with an excess of ozone for the determination of nitrogen monoxide only.
The emitted radiation (chemiluminescence) is proportional to the number of nitrogen monoxide
molecules in the detection volume and thus proportional to the concentration of nitrogen monoxide.
The emitted radiation is filtered by a selective optical filter and converted into an electric signal
by a photomultiplier tube or a photodiode.
For the determination of nitrogen dioxide, the sampled air is fed through a converter where the nitrogen
dioxide is reduced to nitrogen monoxide and analysed in the same way as described previously.
The electrical signal obtained from the photomultiplier tube or photodiode is proportional to the sum of
concentrations of reduced nitrogen dioxide and nitrogen monoxide. The amount of nitrogen dioxide is
calculated from the difference between this concentration and that obtained for nitrogen monoxide only
(when the sampled air has not passed through the converter).
Chemiluminescence is the emission of light during a chemical reaction. During the gas-phase reaction
of nitrogen monoxide and ozone light with an intensity proportional to the concentration of nitrogen
monoxide is produced when electrons of the excited nitrogen dioxide molecules decay to lower energy
states.
This chemiluminescence method is based on the reaction:
*
NO+→O NO + O
(1)
3 22
*
NO →+NO hν (2)
Excited nitrogen dioxide (NO *) emits radiation in the near infrared region (600 nm to 3 000 nm)
with a maximum centred around 1 200 nm. For the determination of nitrogen dioxide, the nitrogen
dioxide present in sampled air is converted to nitrogen monoxide in a converter as a result of the reaction:
converter
NO → NO (3)
The nitrogen monoxide is then analysed according to the reactions (1) and (2).
The concentrations of nitrogen dioxide and nitrogen monoxide are expressed in the units provided
by the calibration standard. The final results for reporting are expressed in µg/m using standard
conversion factors (see Clause 10).
5.3 Type testing
The type test is based on the evaluation of performance characteristics determined under a prescribed
series of tests. In this document, test procedures are described for the determination of the actual values
of the performance characteristics for at least two analysers off the same type in a laboratory
and the same analysers in the field, operated in parallel in both cases. The laboratory tests shall not
include the sampling inlet, sampling system and external data acquisition system, but shall include
analyser sampling line and filter. The field tests may include a sampling inlet and a sampling system.
However, the influence of these components on the test results shall be minimized by proper
maintenance.
A competent body shall perform these tests. The evaluation for type testing of an analyser is based
on the calculation of the expanded uncertainty in the measuring result based on the numerical values
of the tested performance characteristics and compared with a prescribed maximum uncertainty.
The type testing of an analyser and subsequent QA and QC procedures provide evidence that the specified
requirements concerning data quality (see Annex I of Directive 2008/50/EC [1] for more information)
can be satisfied.
Appropriate experimental evidence shall be provided by:
— type tests performed under conditions of intended use of the specified method of measurement, and
— calculation of expanded uncertainty of results of measurement by reference to JCGM 100 [3].
5.4 Field operation and quality control
Prior to the installation and operation of a type-tested analyser at a monitoring station, an expanded
uncertainty calculation shall be performed with the actual values of the performance, obtained during
the type tests, and in accordance with the site-specific conditions at that monitoring station. This
calculation shall be used to demonstrate that the type-tested analyser meets the requirements for all
applicable limit values under the actual conditions present at that specific monitoring station.
After the installation of the type-tested analyser at the monitoring station, its correct functioning
shall be tested.
Requirements for quality assurance and quality control are given in Clause 9 for the operation
and maintenance of the sampling system, as well as for the analyser, to ensure that the associated
uncertainty of measurements obtained in the field is not compromised.
6 Sampling
6.1 General
Depending on the installation of the chemiluminescence analyser at a monitoring station, a single
sampling line for the analyser shall be chosen. Sampling can take place:
— from a sampling inlet with an individual sampling line specific to the analyser
or
— from a common sampling inlet with a sampling manifold to which analysers and equipment may be
attached.
Conditions and layout of the sampling system will contribute to the uncertainty of the measurement; to
minimize this contribution to the expanded uncertainty, requirements for the sampling equipment are
given in the following subclauses.
NOTE In Annex B, different arrangements of the sampling equipment are schematically presented.
The following factors may, through decrease or increase in the concentration of nitrogen dioxide,
contribute to the uncertainty of the measurement when considering the sampling as an integral part
of the measurement:
— loss of nitrogen dioxide in the sampling system;
— loss of nitrogen dioxide in the particle filter;
— formation of nitrogen dioxide due to reaction of nitrogen monoxide with ozone in the sampling
system and in the analyser.
These factors are recognized to be relevant, but currently cannot be quantified for lack of appropriate
assessment methods. As a consequence, the contributions of these factors are not considered
in the uncertainty assessment applied in this document. The effect of these factors is minimized through
minimum requirements (see 6.3) and application of appropriate QA/QC measures (see 9.4 to 9.6)
and maintenance (see 9.7).
6.2 Sampling location
The location where the ambient air shall be sampled and analysed is not specified as this depends
strongly on the category of a monitoring station (such as measurements taken in a rural or background
area).
NOTE More information on guidance and criteria for sampling points on a micro scale are given in Annex III
of Directive 2008/50/EC [1] and Amendment 2015/1480/EC [5]
6.3 Sampling system
6.3.1 Construction
The sampling system shall include a sampling inlet and may include the following components:
— a dedicated sampling line to the analyser or manifold;
— a particle filter placed between the sampling line or manifold and the analyser;
— a sampling pump in case a sampling manifold is used.
The sample inlet shall be constructed in such a way that ingress of rainwater into the sampling line
or manifold is prevented. The sampling line or manifold shall be as short as practical to minimize
the residence time (see also 6.3.3).
In the case where a sampling manifold is used, an additional pump is necessary with sufficient capacity
to fulfil the sampling requirements stated in the previous subclauses (see also 6.5 and Annex B).
The material of the sample inlet as well as the sampling line or manifold can influence the composition
of the sample. In practice, the best materials, such as polytetrafluoroethylene (PTFE), perfluoro-alkoxy
(PFA), borosilicate glass, silicon-coated or 316L stainless steel, shall be used. The influence of the material
of the sampling inlet and line or manifold on the measured concentrations of nitrogen monoxide and
nitrogen dioxide due to losses shall be ≤ 2,0 %.
NOTE 1 When using polymeric materials, consider their permeability to gases and in particular to water vapour.
This effect can be avoided by increasing the thickness of the sampling line or manifold.
NOTE 2 This value can be achieved when the quality assurance and quality control requirements (see Clause 9)
are followed.
The sampling line or manifold may be moderately heated to avoid condensation, which may occur in the
case of high ambient temperature and/or humidity in the presence of cold surfaces.
The influence of the pressure drop on the measured concentration along the sampling inlet, line,
manifold, and the particle filter on the measured concentrations shall be considered (see 9.6.4).
6.3.2 Particle filter
A particle filter shall be placed between the sampling line or manifold and the inlet of the analyser.
The filter shall retain all particles likely to alter the performance of the analyser. It shall be made of PTFE.
The material of the filter housing shall be chemically inert to nitrogen monoxide and nitrogen dioxide.
The filter may be internal to the analyser (see 7.9) or external. In case the analyser contains a built-in
filter, an external filter is not necessary.
NOTE 1 A pore size of the filter of 5 µm usually fulfils this requirement.
NOTE 2 Suitable materials for the filter housing are for example PTFE, PFA, 316L stainless steel, or borosilicate
glass.
The particle filter shall be conditioned before used in measurements (see 6.3.4). The filter shall be
changed periodically depending on the dust loading at the sampling site (as indicated
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...