SIST EN 14212:2025

Ambient air - Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence

This document specifies a continuous measurement method for the determination of the concentration of sulfur dioxide present in ambient air based on the ultraviolet fluorescence measuring principle. This document describes the performance characteristics and sets the relevant minimum criteria required to select an appropriate ultraviolet fluorescence 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 mass concentration of sulphur dioxide present in ambient air up to 1000 µg/m3. This concentration range represents the certification range for sulfur dioxide for 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 Directive 2008/50/EC, the ranges and uncertainty requirements possibly do not apply.
The method covers the determination of ambient air concentrations of sulfur dioxide in locations classified as rural areas, urban-background areas, and for sampling influenced by traffic or industrial sources.
The results are expressed in µg/m3 (at 20 °C and 101,3 kPa).
NOTE 3   1 000 µg/m3 of SO2 corresponds to 376 nmol/mol of SO2.
This document contains information for different groups of users.
Clause 5 to Clause 7 and Annex C and Annex D contain general information about the principles of sulfur dioxide measurement by ultraviolet fluorescence analyser and sampling equipment.
Clause 8 and Annex E are specifically directed towards test houses and laboratories that perform type testing of sulfur dioxide 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 sulfur dioxide 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 sulfur dioxide 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 the measurement results under practical monitoring conditions.
This document represents an evolution of earlier editions (EN 14212:2005 and EN 14212:2012). 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 Schwefeldioxid mit Ultraviolett-Fluoreszenz

Dieses Dokument legt ein kontinuierliches Ultraviolett-Fluoreszenz-Messverfahren zur Bestimmung der Konzentration von Schwefeldioxid in Luft fest. Dieses Dokument nennt die Leistungskenngrößen und legt die Mindestanforderungen für die Eignungsprüfung von Ultraviolett-Fluoreszenz-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 Schwefeldioxid in Luft im Bereich bis 1 000 µg/m3. Dieser Konzentrationsbereich entspricht dem Zertifizierungsbereich für Schwefeldioxid 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 Schwefeldioxid an Standorten, die als ländlich, städtischer Hintergrund, verkehrsbezogen und für Probenahmen unter dem Einfluss von Verkehr oder industrielle Quellen klassifiziert sind.
Die Ergebnisse werden in µg/m3  (bei 20 °C und 101,3 kPa) angegeben.
ANMERKUNG 3   1 000 µg/m3 von SO2 entsprechen 376 nmol/mol SO2.
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 Schwefeldioxid-Messung mit einem Ultraviolett-Fluoreszenz-Messgerät sowie über die Probennahmeeinrichtung.
Abschnitt 8 und Anhang E richten sich speziell an Prüfinstitute und -laboratorien, die Eignungsprüfungen von Schwefeldioxid-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 Schwefeldioxid-Messgeräts anhand der Eignungsprüfungsergebnisse.
Abschnitt 9 bis Abschnitt 11 und Anhang F und Anhang G richten sich an die Betreiber von Messnetzen, mit denen Schwefeldioxid-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 14212:2005 und EN 14212:2012) 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 de soufre par fluorescence U.V.

Le présent document spécifie une méthode de mesure en continu pour la détermination de la concentration en dioxyde de soufre dans l’air ambiant, selon le principe de mesure par fluorescence U.V. Le présent document décrit les caractéristiques de performance et fixe les critères minimaux requis pour sélectionner un analyseur par fluorescence U.V. à l’aide de l’essai de type. Il présente également l'évaluation de l'aptitude à l'emploi d'un analyseur sur un site fixe spécifique afin de répondre aux exigences de qualité des données (voir l'Annexe I de la Directive 2008/50/CE [1] pour des informations supplémentaires) 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 massique en dioxyde de soufre présent dans l'air ambiant jusqu'à 1 000 µg/m3. Cette plage de concentration représente l’étendue de mesure certifiée en dioxyde de soufre pour l’essai de type.
NOTE 1   D'autres plages peuvent être utilisées selon les niveaux présents dans l'air ambiant.
NOTE 2   Des exemples de calculs de bilans d'incertitude sont donnés aux Annexes E à H en référence à la Directive 2008/50/CE [1]. Si les valeurs limites sont actualisées dans les versions ultérieures de la Directive 2008/50/CE [1], l'utilisateur peut utiliser ces nouvelles valeurs pour calculer les incertitudes de mesure.
La méthode couvre la détermination des concentrations en dioxyde de soufre présent 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   1 000 µg/m3 de SO2 correspondent à 376 nmol/mol de SO2.
Le présent document contient des informations pour différents groupes d'utilisateurs.
Les Articles 5 à 7 ainsi que l'Annexe C et l'Annexe D contiennent des informations générales relatives aux principes de mesure du dioxyde de soufre à l'aide d'un analyseur par fluorescence U.V. et d'un équipement de prélèvement.
L'Article 8 et Annexe E concernent tout particulièrement les organismes et les laboratoires d'essai qui effectuent l’essai de type des analyseurs de dioxyde de soufre. Ces sections contiennent des informations concernant :
-   les conditions de l’essai de type, les procédures de test et les exigences d'essai ;
-   les exigences de performance de l'analyseur ;
-   l'évaluation des résultats de l’essai de type ;
-   l'évaluation de l'incertitude des résultats de mesure de l'analyseur de dioxyde de soufre d'après les résultats de l’essai de type.
Les Articles 9 à 11 ainsi que l'Annexe F, l'Annexe G et l'Annexe H concernent les réseaux de surveillance effectuant les mesurages concrets du dioxyde de soufre 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 associée aux mesures sous des conditions de surveillance réelles.
Le présent document représente une évolution par rapport aux éditions antérieures (EN 14212:2005 et EN 14212:2012).
NOTE 4   Les analyseurs soumis à essai de type avant la publication du présent document peuvent toujours être utilisés à des fins de surveillance réglementaire. Au fur et à mesure que de nouvelles versions des analyseurs testés dans le cadre du présent document sont disponibles, cesser d'utiliser les anciens analyseurs de référence.

Zunanji zrak - Standardna metoda za določanje koncentracije žveplovega dioksida z ultravijolično fluorescenco

Ta dokument določa metodo stalnega merjenja za določitev koncentracije žveplovega dioksida v zunanjem zraku na podlagi fluorescentnega ultravijoličnega merilnega principa. Ta dokument opisuje lastnosti delovanja in vzpostavlja ustrezna minimalna merila, potrebna za izbiro ustreznega fluorescentnega ultravijoličnega 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 masne koncentracije žveplovega dioksida v zunanjem zraku do vrednosti 1000 μg/m3. Te koncentracije predstavljajo razpon certificiranja za žveplov dioksid 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 E 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 žveplovega dioksida 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: 1000 µg/m3 žveplovega dioksida (SO2) ustreza 376 nmol/mol žveplovega dioksida.
Ta dokument vsebuje informacije za različne skupine uporabnikov.
Točke od 5 do 7 ter dodatka C in D vsebujejo splošne informacije o načelih merjenja žveplovega dioksida z ultravijoličnimi fluorescentnimi analizatorji in opremo za vzorčenje.
Osrednji predmet obravnave v točki 8 in dodatku E so laboratoriji, ki izvajajo tipske preskuse analizatorjev žveplovega dioksida. 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 žveplovega dioksida na podlagi rezultatov tipskih preskusov.
Osrednji predmet obravnave v točkah od 9 do 11 ter dodatkih F in H so mreže za spremljanje, ki izvajajo praktične meritve žveplovega dioksida 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 negotovosti rezultatov merjenja v okviru pogojev praktičnega spremljanja.
Ta dokument je nadgradnja prejšnjih različic (EN 14212:2005 in EN 14212:2012).

General Information

• Status: Published
• Public Enquiry End Date: 02-Jan-2023
• Publication Date: 03-Mar-2025
• ICS: 13.040.20 - Ambient atmospheres
• Technical Committee: KAZ - Air quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 10-Feb-2025
• Due Date: 17-Apr-2025
• Completion Date: 04-Mar-2025
• 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
• Directive: 2011-01-2525 - Pravilnik o ocenjevanju kakovosti zunanjega zraka
• Ref Project: EN 14212:2024 - Ambient air - Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence

Relations

• Replaces: SIST EN 14212:2012/AC:2014 - Ambient air - Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence
• Effective Date: 01-Apr-2025
• Replaces: SIST EN 14212:2012 - Ambient air - Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence
• Effective Date: 01-Apr-2025

Overview

EN 14212:2024 (CEN) - Ambient air: Standard method for the measurement of the concentration of sulphur dioxide by ultraviolet fluorescence - specifies a continuous measurement method for determining sulphur dioxide (SO2) in ambient air using the ultraviolet fluorescence principle. The standard defines performance characteristics, minimum criteria for type testing ultraviolet fluorescence analysers and gives procedures for on-site installation, sampling, calibration, quality assurance and uncertainty evaluation to meet data quality requirements (including those of Directive 2008/50/EC). The certified concentration range for type testing is up to 1000 µg/m3 (expressed as µg/m3 at 20 °C and 101,3 kPa).

Key topics and requirements

• Measuring principle: UV fluorescence detection of SO2 and related instrumental requirements.
• Type testing: Laboratory and field procedures, performance characteristics, test gases and purity specifications, and uncertainty calculation for analyser certification.
• Performance criteria: Minimum acceptance limits for sensitivity, linearity, detection limit, response time, stability and interferents.
• Sampling & analyser equipment: Recommendations for sampling location, manifold and sampling system design, flow control, pumps, filters and selective traps.
• Field operation & QA/QC: Initial installation checks, ongoing calibration frequency, maintenance, checks, and data handling/reporting.
• Uncertainty evaluation: Methods to calculate measurement uncertainty from type test and field data; procedures tailored for test houses and monitoring networks.
• Scope of application: Suitable for rural, urban-background, traffic-influenced and industrial-influenced sites; note that other concentration ranges may be used where appropriate.

Practical applications and users

Who benefits from EN 14212:2024:

• Environmental regulators and air quality authorities implementing compliance monitoring under Directive 2008/50/EC.
• Monitoring networks and fixed-site stations conducting continuous ambient SO2 measurements.
• Test houses and laboratories performing type testing and instrument certification.
• Manufacturers and procurement officers selecting and validating ultraviolet fluorescence analysers.
• Air quality consultants and researchers needing standardized procedures for calibration, QA/QC and uncertainty assessment.

Practical uses:

• Selecting analysers that meet certified performance for regulatory monitoring.
• Implementing standardized sampling systems and calibration regimes to ensure data comparability.
• Calculating and reporting SO2 concentrations and measurement uncertainty for compliance and public reporting.

Related standards and notes

• Builds on earlier editions EN 14212:2005 and EN 14212:2012 - procurement is recommended to comply fully with the 2024 edition.
• Linked to Directive 2008/50/EC data quality requirements; when used outside regulatory contexts some ranges or uncertainty requirements may not apply.

Standards Content (Sample)

SLOVENSKI STANDARD
01-april-2025
Nadomešča:
SIST EN 14212:2012
SIST EN 14212:2012/AC:2014
Zunanji zrak - Standardna metoda za določanje koncentracije žveplovega dioksida
z ultravijolično fluorescenco
Ambient air - Standard method for the measurement of the concentration of sulphur
dioxide by ultraviolet fluorescence
Außenluft - Messverfahren zur Bestimmung der Konzentration von Schwefeldioxid mit
Ultraviolett-Fluoreszenz
Air ambiant - Méthode normalisée pour le mesurage de la concentration en dioxyde de
soufre par fluorescence U.V.
Ta slovenski standard je istoveten z: EN 14212:2024
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 14212
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2024
EUROPÄISCHE NORM
ICS 13.040.20 Supersedes EN 14212:2012
English Version
Ambient air - Standard method for the measurement of the
concentration of sulphur dioxide by ultraviolet
fluorescence
Air ambiant - Méthode normalisée pour le mesurage de Außenluft - Messverfahren zur Bestimmung der
la concentration en dioxyde de soufre par fluorescence Konzentration von Schwefeldioxid mit Ultraviolett-
U.V. Fluoreszenz
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 14212:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 8
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 11
4 Abbreviated terms . 16
5 Principle . 17
5.1 General . 17
5.2 Measuring principle . 17
5.3 Type testing . 18
5.4 Field operation and quality control. 18
6 Sampling . 18
6.1 General . 18
6.2 Sampling location . 19
6.3 Sampling system . 19
6.4 Control and regulation of sample flow rate . 20
6.5 Sampling pump for the manifold . 20
7 Analyser equipment . 21
7.1 General . 21
7.2 Selective traps for interfering agents . 21
7.3 Optical assembly. 21
7.4 Pressure measurement . 21
7.5 Flow rate indicator . 22
7.6 Sampling pump for the analyser . 22
7.7 Internal sulfur dioxide span source . 22
7.8 Particle filter . 22
8 Type testing of ultraviolet fluorescence sulfur dioxide analysers . 22
8.1 General . 22
8.2 Relevant performance characteristics and criteria . 23
Table 1 — Relevant performance characteristics and criteria . 24
8.3 Design change . 26
8.4 Procedures for determination of the performance characteristics during the
laboratory test . 26
Table 2 — Set points and stability of test parameters . 27
Table 3 — Methods for preparation of test gases . 27
Table 4a — Specification for purity of test gas . 28
Table 4b — Specification for purity of zero gas for interferents testing [9] . 28
Table 4c — Specification for purity of zero gas for other tests [9] . 28
Figure 1 — Diagram illustrating the response time . 30
Figure 2 — Concentration variations for the averaging effect test . 37
8.5 Determination of the performance characteristics during the field test. 38
8.6 Type testing and uncertainty calculation . 42
9 Field operation and ongoing quality control . 42
9.1 General . 42
9.2 Suitability evaluation . 43
Table 5 — Site-specific conditions to be evaluated . 43
9.3 Initial installation . 44
9.4 Ongoing quality assurance/quality control . 46
Table 6 — Required frequency of calibration, checks and maintenance . 47
9.5 Calibration of the analyser . 49
Figure 3 — Flow scheme for performance of evaluation of effects of violation of
performance requirements and possibilities for data correction . 52
9.6 Checks . 53
9.7 Maintenance . 56
9.8 Data handling and data reports . 57
9.9 Measurement uncertainty . 57
10 Expression of results . 58
11 Test reports and documentation . 58
11.1 Type testing . 58
11.2 Field operation . 59
Annex A (normative) Test of lack of fit . 61
A.1 Establishment of the regression line . 61
A.2 Calculation of the residuals of the averages . 61
Annex B (informative) Sampling equipment . 63
Figure B.1 — Sampling layout with a main sampling manifold . 63
Figure B.2 — Sampling layout with individual lines . 64
Annex C (informative) Ultraviolet fluorescence analyser . 65
Figure C.1 — Schematic diagram of a UV fluorescence sulfur dioxide analyser . 65
Annex D (informative) Manifold testing . 66
D.1 Procedure for applying test gas . 66
Figure D.1 — Schematic diagram of manifold testing equipment . 67
D.2 Procedure for the cross test . 67
D.2.1 General . 67
D.2.2 Initial stage . 67
D.2.3 Stage 1 . 68
D.2.4 Stage 2 . 68
D.2.5 Data Processing . 68
D.2.6 Evaluation . 68
Annex E (normative) Type testing . 70
E.1 Type testing and uncertainty calculation . 70
E.1.1 Type testing . 70
E.1.2 Uncertainty calculation . 70
E.2 Type testing Requirement a) . 70
Table E.1 — Relevant performance characteristics and criteria . 71
E.3 Type testing Requirement b) . 72
E.3.1 General . 72
Table E.2 — Standard uncertainties to be incorporated in the calculation of the expanded
uncertainty after the laboratory tests . 73
Table E.3 — Standard uncertainty of the calibration gas to be incorporated in the
calculation of the expanded uncertainty after the laboratory tests . 73
E.3.2 Calculation of standard uncertainties . 75
E.3.2.1 General . 75
E.3.2.2 Repeatability at zero . 75
E.3.2.3 Repeatability at the hourly limit value of sulfur dioxide . 75
E.3.2.4 Lack of fit . 76
E.3.2.5 Influence quantities . 76
E.3.2.5.1 General . 76
E.3.2.5.2 Sample gas pressure . 77
E.3.2.5.3 Sample gas temperature . 77
E.3.2.5.4 Surrounding temperature . 78
E.3.2.5.5 Electrical voltage . 78
E.3.2.5.6 Water vapour . 79
E.3.2.5.7 Other interferents. 79
E.3.2.5.8 Averaging effect . 80
E.3.2.5.9 Calibration gas . 81
E.3.2.5.10 Difference sample/calibration port . 81
E.3.3 Example calculation . 82
Table E.4 —Example calculation . 82
E.4 Type testing Requirement c) . 84

Table E.5 — Relevant performance characteristics and criteria . 84
E.5 Type testing Requirement d) . 84
E.5.1 General . 84
Table E.6 — Standard uncertainties to be incorporated in the calculation of the expanded
uncertainty after the laboratory and field tests. 85
Table E.7 — Standard uncertainty of the calibration gas to be incorporated in the
calculation of the expanded uncertainty after the laboratory and field tests . 85
E.5.2 Combined standard uncertainty . 86
E.5.3 Absolute expanded uncertainty . 86
E.5.4 Relative expanded uncertainty . 87
E.5.5 Calculation of standard uncertainties . 87
E.5.6 Example calculation . 89
Table E.8 —Example calculation . 89
Annex F (informative) Calculation of uncertainty in field operation at the hourly limit value . 91
F.1 General . 91
F.2 Combined standard uncertainty . 91
F.3 Standard uncertainties . 92
F.3.1 General . 92
F.3.1.1 General . 92
F.3.1.2 Repeatability at zero . 92
F.3.1.3 Repeatability at the hourly limit value . 92
F.3.1.4 Lack of fit . 92
F.3.2 Influence quantities . 93
F.3.2.1 General . 93
F.3.2.2 Sample gas pressure . 93
F.3.2.3 Sample gas temperature . 93
F.3.2.4 Surrounding temperature . 94
F.3.2.5 Electrical voltage . 95
F.3.3 Interferents . 95
F.3.3.1 Water vapour . 95
F.3.3.2 Other interferents . 96
F.3.4 Averaging effect . 96
F.3.5 Reproducibility under field conditions . 96
F.3.6 Long-term drift at zero . 97
F.3.7 Long-term drift at level of the hourly limit value . 97
F.3.8 Zero gas . 97
F.3.9 Calibration gas . 97
F.3.10 Difference sample/calibration port . 97
F.4 Example calculation . 98
Table F.1 —Example calculation . 98
Annex G (informative) Calculation of uncertainty in field operation at the daily limit value . 100
G.1 General . 100
G.2 Combined standard uncertainty . 100
G.3 Standard uncertainties . 101
G.3.1 General . 101
G.3.1.1 General . 101
G.3.1.2 Repeatability at zero . 101
G.3.1.3 Repeatability at the daily limit value . 102
G.3.1.4 Lack of fit . 102
G.3.2 Influence quantities . 102
G.3.2.1 General . 102
G.3.2.2 Sample gas pressure . 103
G.3.2.3 Sample gas temperature . 103
G.3.2.4 Surrounding temperature . 104
G.3.2.5 Electrical voltage . 104
G.3.3 Interferents . 105
G.3.3.1 General . 105
G.3.3.2 Water vapour . 105
G.3.3.3 Other interferents . 106
G.3.4 Averaging effect . 107
G.3.5 Zero gas . 107
G.3.6 Calibration gas . 107
G.3.7 Difference sample/calibration port . 107
G.3.8 Reproducibility under field conditions . 108
G.3.9 Long-term drift at zero . 108
G.3.10 Long-term drift at level of the daily limit value . 108
G.4 Example calculation . 109
Table G.1 —Example calculation . 109
Annex H (informative) Calculation of uncertainty in field operation at the annual critical
level . 111
H.1 General . 111
H.2 Combined standard uncertainty . 111
H.3 H.3 Standard uncertainties . 113
H.3.1 General . 113
H.3.2 Repeatability at zero . 113
H.3.3 Repeatability at the annual limit value . 113
H.3.4 Lack of fit . 114
H.3.5 Influence quantities . 114
H.3.5.1 General . 114
H.3.5.2 Sample gas pressure . 114
H.3.5.3 Sample gas temperature . 115
H.3.5.4 Surrounding temperature . 115
H.3.5.5 Electrical voltage . 116
H.3.5.6 Interferents . 117
H.3.5.7 Water vapour . 117
H.3.5.8 Other interferents . 117
H.3.6 Averaging effect . 118
H.3.7 Zero gas . 119
H.3.8 Calibration gas . 119
H.3.9 Difference sample/calibration port . 119
H.3.10 Reproducibility under field conditions . 120
H.3.11 Long term drift at zero . 120
H.3.12 Long term drift at level of the annual critical level . 121
Annex I (informative) Test stand for the test point “sensitivity coefficient of sample gas
pressure”. 122
Figure I.1 — Test stand for the test point “sensitivity coefficient of sample gas pressure” . 122
Annex J (informative) Significant technical changes . 123
Table J.1 —Details of significant technical changes between this document and the previous
edition . 123
Bibliography . 124

European foreword
This document (EN 14212:2024) 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 14212:2012.
The technical modifications in comparison with the previous edition are listed in Annex J
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 concentration
of sulfur dioxide present in ambient air based on the ultraviolet fluorescence measuring principle. This
document describes the performance characteristics and sets the relevant minimum criteria required to
select an appropriate ultraviolet fluorescence 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 mass concentration of sulfur dioxide present
in ambient air up to 1000 µg/m . This concentration range represents the certification range for sulfur
dioxide for 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 E 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 sulfur dioxide in zones classified
as rural areas, urban-background areas, traffic-oriented locations and locations influenced by industrial
sources.
The results are expressed in µg/m (at 20 °C and 101,3 kPa).
NOTE 3 1 000 µg/m of SO corresponds to 376 nmol/mol of SO .
2 2
This document contains information for different groups of users.
Clause 5 to Clause 7 and Annex C and Annex D contain general information about the principles of sulfur
dioxide measurement by ultraviolet fluorescence analyser and sampling equipment.
Clause 8 and Annex E are specifically directed towards test houses and laboratories that perform type
testing of sulfur dioxide 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 associated uncertainty of the measurement performed by the sulfur dioxide
analyser based on the type testing results.
Clause 9 to Clause 11 and Annex F, Annex G and Annex H are directed towards monitoring networks
performing the practical measurements of sulfur dioxide 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 the measurement results under practical monitoring conditions.
This document represents an evolution of earlier editions (EN 14212:2005 and EN 14212:2012).
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, Gas analysis — Preparation of calibration gas mixtures — Gravimetric method (ISO 6142)
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)
EN 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 excludes 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 may be expressed by a statement, calibration function, calibration diagram,
calibration curve, or calibration table. In some cases, it may 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
...