Ambient air - Standard method for the measurement of the concentration of carbon monoxide by non-dispersive infrared spectroscopy

This European Standard specifies a continuous measurement method for the determination of the concentration of carbon monoxide present in ambient air based on the non-dispersive infrared spectroscopic measuring principle. This standard describes the performance characteristics and sets the relevant minimum criteria required to select an appropriate non-dispersive infrared spectroscopic analyser by means of type approval tests. 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 con¬centration of carbon monoxide present in ambient air up to 100 mg/m3 carbon monoxide. This concentration range represents the certification range for CO for the type approval test.
NOTE 1   Other ranges may be used depending on the levels present in ambient air.
NOTE 2   When the standard is used for other purposes than for measurements required by Directive 2008/50/EC, the ranges and uncertainty requirements may not apply.
The method covers the determination of ambient air concentrations of carbon monoxide in areas classified as rural, urban-background and traffic-orientated and those influenced by industrial sources.  
The results are expressed in mg/m3 (at 20 °C and 101,3 kPa).
NOTE 3   100 mg/m3 of CO corresponds to 86 mol/mol of CO.
This standard contains information for different groups of users.
Clauses 5 to 7 and Annexes B, C and D contain general information about the principles of carbon monoxide measurement by non-dispersive infrared spectroscopic analyser and sampling equipment.
Clause 8 and Annex E are specifically directed towards test houses and laboratories that perform type-approval testing of carbon monoxide analysers. These sections contain information about:
-   Type-approval test conditions, test procedures and test requirements;
-   Analyser performance requirements;
-   Evaluation of the type-approval test results;
-   Evaluation of the uncertainty of the measurement results of the carbon monoxide analyser based on the type-approval test results.
Clauses 9 to 11 and Annex F are directed towards monitoring networks performing the practical measurements of carbon monoxide 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.

Außenluft - Messverfahren zur Bestimmung der Konzentration von Kohlenmonoxid mit nicht-dispersiver Infrarot-Photometrie

Dieses Dokument legt ein kontinuierliches Messverfahren nach dem nicht-dispersiven Infrarot-Messprinzip zur Bestimmung der Konzentration von Kohlenmonoxid in Außenluft fest. Es nennt die Leistungs¬kenngrößen und legt die Mindestanforderungen für die Eignungsprüfung von Infrarot-Photometern 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 Kohlenmonoxid in Außenluft bis 100 mg/m3. Dieser Konzentrationsbereich entspricht dem Zertifizierungsbereich für die Eignungsprüfung.
ANMERKUNG 1      Je nach Konzentrationsniveau in der Luft können auch andere Bereiche gewählt werden.
ANMERKUNG 2      Wird diese Norm 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 Kohlenmonoxid 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   100 mg/m3 Kohlenmonoxid entsprechen 86 µmol/mol Kohlenmonoxid.
Dieses Dokument enthält Informationen für verschiedene Nutzergruppen.
Die Abschnitte 5 bis 7 und die Anhänge B bis D enthalten allgemeine Informationen über die Grundlagen der Kohlenmonoxid-Messung mit einem nicht-dispersiven Infrarot-Photometer sowie über die Probennahme-einrichtung.
Abschnitt 8 und Anhang E richten sich speziell an Prüfinstitute und -laboratorien, die Eignungsprüfungen von Kohlenmonoxid-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 Kohlenmonoxid-Messgeräts anhand der Eignungsprüfungsergebnisse.
Die Abschnitte 9 bis 11 und die Anhang F richten sich an die Betreiber von Messnetzen, mit denen Kohlenmonoxid-Messungen in Außenluft 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.

Air ambiant - Méthode normalisée de mesurage de la concentration en monoxyde de carbone par spectroscopie à rayonnement infrarouge non dispersif

La présente Norme européenne spécifie une méthode de mesurage en continu pour la détermination de la concentration en monoxyde de carbone dans l’air ambiant, selon le principe de mesure par spectroscopie à rayonnement infrarouge non dispersif. La présente norme décrit les caractéristiques de performance et fixe les critères minimaux requis pour sélectionner un analyseur par spectroscopie à rayonnement infrarouge non dispersif à l’aide d’essais d’approbation de type. Elle présente également l’évaluation de l’aptitude à l’emploi d’un analyseur sur un site fixe spécifique de manière à répondre aux exigences de qualité des données spécifiées dans 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 massique en monoxyde de carbone présent dans l’air ambiant jusqu’à 100 mg/m3. Cette plage de concentration représente l’étendue de mesure certifiée pour l’essai d’approbation de type.
NOTE 1   D’autres plages peuvent être utilisées selon les niveaux présents dans l’air ambiant.
NOTE 2   Lorsque la norme est utilisée à d’autres fins que 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 monoxyde de carbone 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 mg/m3 (à 20 °C et 101,3 kPa).
NOTE 3   100 mg/m3 de CO correspondent à 86 µmol/mol de CO.
La présente norme contient des informations pour différents groupes d’utilisateurs.
Les Articles 5 à 7 et les Annexes B, C et D contiennent des informations générales relatives aux principes de mesurage du monoxyde de carbone à l’aide d’un analyseur par spectroscopie à rayonnement infrarouge non dispersif et d’un équipement de prélèvement.
L’Article 8 et l’Annexe E concernent tout particulièrement les entreprises et les laboratoires d’essai qui effectuent des essais d’approbation de type des analyseurs de monoxyde de carbone. Ces sections contiennent des informations concernant :
-   les conditions de l’essai d’approbation de type, les modes opératoires d’essai et les exigences d’essai ;
-   les exigences de performance de l’analyseur ;
-   l’évaluation des résultats de l’essai d’approbation de type ;
-   l’évaluation de l’incertitude des résultats de mesurage de l’analyseur de monoxyde de carbone d’après les résultats de l’essai d’approbation de type.
Les Articles 9 à 11 et les Annexes F à H concernent les réseaux de surveillance effectuant les mesurages pratiques du monoxyde de carbone 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 mesurage ;
-   l’évaluation de l’incertitude des résultats de mesurage sous des conditions de surveillance pratiques.

Zunanji zrak - Standardna metoda za določevanje koncentracije ogljikovega monoksida z nedisperzivno infrardečo spektroskopijo

Ta evropski standard določa metodo stalnega merjenja za določitev koncentracije ogljikovega monoksida v zunanjem zraku na podlagi principa nedisperzne infrardeče spektrometrije. Ta standard opisuje lastnosti delovanja in vzpostavlja ustrezna minimalna merila, potrebna za izbiro ustreznega nedisperznega infrardečega spektroskopskega analizatorja s homologacijskimi preizkusi. Vključuje tudi oceno ustreznosti analizatorja za uporabo na specifičnem fiksnem mestu, da se izpolnijo zahteve o kakovosti podatkov, kot je opredeljeno v Prilogi I Direktive 2008/50/ES, ter zahteve med vzorčenjem, kalibriranjem in zagotavljanjem kakovosti za uporabo. Ta metoda velja za določitev masne koncentracije ogljikovega monoksida v zunanjem zraku do vrednosti 100 mg/m3 ogljikovega monoksida. Ta razpon koncentracij predstavlja razpon certificiranja za homologacijski preizkus. Ta metoda pokriva določitev koncentracij ogljikovega 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 mg/m3 (pri 20 °C in 101,3 kPa). Ta standard vsebuje informacije za različne skupine uporabnikov. Določbe od 5 do 7 ter dodatki B, C in D vsebujejo splošne informacije o načelih merjenja ogljikovega monoksida z nedisperznim infrardečim spektroskopskim analizatorjem in opremo za vzorčenje. Osrednji predmet obravnave določbe 8 in dodatka E so laboratoriji, ki izvajajo homologacijske preizkuse analizatorjev ogljikovega monoksida. Ti razdelki vsebujejo informacije o naslednjem: – pogoji homologacijskih preizkusov, preizkusni postopki in zahteve; – zahteve glede učinkovitosti analizatorja; ocena rezultatov homologacijskih preizkusov; ocena negotovosti rezultatov merjenja analizatorja ogljikovega monoksida na podlagi rezultatov homologacijskih preizkusov. Osrednji predmet obravnave določb od 9 do 11 in dodatka F so omrežja za spremljanje stanja, ki izvajajo praktično merjenje ogljikovega monoksida v zunanjem zraku. Ti razdelki vsebujejo informacije o naslednjem: – začetna namestitev analizatorja v omrežju za spremljanje stanja in preizkušanje ustreznosti; – tekoče zagotavljanje kakovosti/nadzor kakovosti; izračun in poročanje rezultatov merjenja; ocena negotovosti rezultatov merjenja pod pogoji praktičnega spremljanja.

General Information

Status
Published
Publication Date
21-Aug-2012
Current Stage
9093 - Decision to confirm - Review Enquiry
Due Date
04-Mar-2018
Completion Date
07-Mar-2018

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.MLNRYHJDLuftqualität - Messverfahren zur Bestimmung der Konzentration von Kohlenmonoxid mit nicht-dispersiver Infrarot-PhotometrieAir ambiant - Méthode normalisée de mesurage de la concentration en monoxyde de carbone par spectroscopie à rayonnement infrarouge non dispersifAmbient air - Standard method for the measurement of the concentration of carbon monoxide by non-dispersive infrared spectroscopy13.040.20Kakovost okoljskega zrakaAmbient atmospheresICS:Ta slovenski standard je istoveten z:EN 14626:2012SIST EN 14626:2012en,fr,de01-december-2012SIST EN 14626:2012SLOVENSKI

STANDARDSIST EN 14626:20051DGRPHãþD
SIST EN 14626:2012
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 14626
August 2012 ICS 13.040.20 Supersedes EN 14626:2005English Version

Ambient air - Standard method for the measurement of the concentration of carbon monoxide by non-dispersive infrared spectroscopy

Air ambiant - Méthode normalisée de mesurage de la concentration en monoxyde de carbone par spectroscopie à rayonnement infrarouge non dispersif

Luftqualität - Messverfahren zur Bestimmung der Konzentration von Kohlenmonoxid mit nicht-dispersiver Infrarot-Photometrie This European Standard was approved by CEN on 10 May 2012.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,

B-1000 Brussels © 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 14626:2012: ESIST EN 14626:2012

EN 14626:2012 (E) 2 Contents Contents ...................................................................................................................................................................... 2Foreword ...................................................................................................................................................................... 41Scope .............................................................................................................................................................. 52Normative references .................................................................................................................................... 63Terms and definitions ................................................................................................................................... 64Abbreviated terms ....................................................................................................................................... 105Principle ........................................................................................................................................................ 115.1General .......................................................................................................................................................... 115.2Measuring principle ..................................................................................................................................... 115.3Type approval test ....................................................................................................................................... 115.4Field operation and quality control ............................................................................................................ 126Sampling ....................................................................................................................................................... 126.1General .......................................................................................................................................................... 126.2Sampling location ........................................................................................................................................ 126.3Sampling system ......................................................................................................................................... 126.4Control and regulation of sample flow rate .............................................................................................. 136.5Sampling pump for the manifold ................................................................................................................ 147Analyser equipment .................................................................................................................................... 147.1General .......................................................................................................................................................... 147.2Interferents ................................................................................................................................................... 147.3Details about analyser equipment ............................................................................................................. 147.4Pressure measurement ............................................................................................................................... 157.5Flow rate indicator ....................................................................................................................................... 157.6Sampling pump for the analyser ................................................................................................................ 157.7Particle filter ................................................................................................................................................. 158Type approval of carbon monoxide analysers ......................................................................................... 158.1General .......................................................................................................................................................... 158.2Relevant performance characteristics and performance criteria ........................................................... 168.3Design change ............................................................................................................................................. 188.4Procedures for determination of the performance characteristics during the laboratory test ........... 188.5Determination of the performance characteristics during the field test ................................................ 288.6Expanded uncertainty calculation for type approval ............................................................................... 329Field operation and ongoing quality control ............................................................................................ 339.1General .......................................................................................................................................................... 339.2Suitability evaluation ................................................................................................................................... 33SIST EN 14626:2012

EN 14626:2012 (E) 3 9.3Initial installation ......................................................................................................................................... 359.4Ongoing quality assurance/quality control............................................................................................... 369.5Calibration of the analyser.......................................................................................................................... 389.6Checks .......................................................................................................................................................... 399.7Maintenance ................................................................................................................................................. 439.8Data handling and data reports .................................................................................................................. 449.9Measurement uncertainty ........................................................................................................................... 4410Expression of results .................................................................................................................................. 4511Test reports and documentation ................................................................................................................ 4511.1Type approval test ....................................................................................................................................... 4511.2Field operation ............................................................................................................................................. 46Annex A (normative)

Test of lack of fit ................................................................................................................... 48Annex B (informative)

Sampling equipment........................................................................................................... 50Annex C (informative)

Schematics of non-dispersive infrared spectrometer .................................................... 52Annex D (informative)

Manifold testing .................................................................................................................. 54Annex E (normative)

Type approval ........................................................................................................................ 56Annex F (informative)

Calculation of uncertainty in field operation at the 8-hour limit value .......................... 75Annex G (informative)

Significant technical changes ........................................................................................... 83Bibliography .............................................................................................................................................................. 84 SIST EN 14626:2012

EN 14626:2012 (E) 4 Foreword This document (EN 14626:2012) 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 February 2013, and conflicting national standards shall be withdrawn at the latest by February 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 14626:2005. The technical changes made since EN 14211:2005 are listed in Annex G of this European Standard.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 14626:2012

EN 14626:2012 (E) 5 1 Scope This European Standard specifies a continuous measurement method for the determination of the concentration of carbon monoxide present in ambient air based on the non-dispersive infrared spectroscopic measuring principle. This standard describes the performance characteristics and sets the relevant minimum criteria required to select an appropriate non-dispersive infrared spectroscopic analyser by means of type approval tests. 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 carbon monoxide present in ambient air up to 100 mg/m3 carbon monoxide. This concentration range represents the certification range for the type approval test. NOTE 1 Other ranges may be used depending on the levels present in ambient air.

NOTE 2 When the standard is used for other purposes than for measurements required by Directive 2008/50/EC, the ranges and uncertainty requirements may not apply. The method covers the determination of ambient air concentrations of carbon monoxide in zones classified as rural areas, urban-background areas and traffic-orientated locations and locations influenced by industrial sources.

The results are expressed in mg/m3 (at 20 °C and 101,3 kPa). NOTE 3 100 mg/m3 of CO corresponds to 86 µmol/mol of CO. This standard contains information for different groups of users. Clauses 5 to 7 and Annexes B, C and D contain general information about the principles of carbon monoxide measurement by non-dispersive infrared spectroscopic analyser and sampling equipment. Clause 8 and Annex E are specifically directed towards test houses and laboratories that perform type-approval testing of carbon monoxide analysers. These sections contain information about:  type-approval test conditions, test procedures and test requirements;  analyser performance requirements;  evaluation of the type-approval test results;  evaluation of the uncertainty of the measurement results of the carbon monoxide analyser based on the type-approval test results. Clauses 9 to 11 and Annex F are directed towards monitoring networks performing the practical measurements of carbon monoxide 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.

SIST EN 14626:2012

EN 14626:2012 (E) 6 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. 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 — Certification of automated measuring systems — Part 1: General principles EN 15267-2, 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 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 methods

(ISO 6144) EN ISO 6145-6, Gas analysis — Preparation of calibration gas mixtures using dynamic volumetric methods — Part 6: Critical orifices (ISO 6145-6) EN ISO 6145-7, Gas analysis — Preparation of calibration gas mixtures using dynamic volumetric methods — Part 7: Thermal mass-flow controllers (ISO 6145-7) EN ISO 14956, Air quality — Evaluation of the suitability of a measurement procedure by comparison with a required measurement uncertainty (ISO 14956) EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories

(ISO/IEC 17025) ENV 13005:1999, Guide to the expression of uncertainty in measurement

3 Terms and definitions For the purpose of this document, the following terms and definitions apply. 3.1 adjustment 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. [SOURCE: JCGM 200:2012 (VIM) [2]] Note 3 to entry:

In the context of this standard, adjustment is performed on measurement data rather than on the analyser. 3.2 ambient air outdoor air in the troposphere, excluding workplaces as defined by Directive 89/654/EEC, where provisions concerning health and safety at work apply and to which members of the public do not have regular access [SOURCE: 2008/50/EC[1]] SIST EN 14626:2012

EN 14626:2012 (E) 7 3.3 analyser measuring system that provides an output signal which is a function of the concentration, partial pressure, flow or temperature of one or more components of a 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 perceived as being calibration.

[SOURCE: JCGM 200:2012 (VIM) [2]] Note 4 to entry:

In the context of this standard, 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. 3.6 certification range concentration range for which the analyser is type-approved 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: ENV 13005:1999] 3.9 coverage factor numerical factor used as a multiplier of the combined standard uncertainty in order to obtain an expanded uncertainty [SOURCE: ENV 13005:1999] 3.10 designated body body which has been designated for a specific task (type approval tests and/or QA/QC activities in the field) by the competent authority in the Member States SIST EN 14626:2012

EN 14626:2012 (E) 8 3.11 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 x (sz/B) where sz is the standard deviation of analyser response at zero measurand concentration (see 8.4.5) and B is the slope of the calibration function [3].

3.12 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 characterised 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: ENV 13005:1999] Note 3 to entry: For the purpose of this standard 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 %. 3.13 fall time difference between the response time (fall) and the lag time (fall) 3.14 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. 3.15 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]. 3.16 influence quantity quantity that is not the measurand but that affects the result of the measurement

[SOURCE: ENV 13005:1999] 3.17 interferent component of the air sample, excluding the measured constituent, that affects the output signal 3.18 lack of fit maximum deviation from the linear regression line of the average of a series of measurement results at the same concentration

SIST EN 14626:2012

EN 14626:2012 (E) 9 3.19 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 3.20 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 [1]] 3.21 long term drift difference between zero or span readings over a determined period of time (e.g. period of unattended operation) 3.22 monitoring station enclosure located in the field in which an analyser has been installed to monitor concentrations of one or more ambient air pollutants

3.23 parallel measurements measurements from different analysers, sampling from one and the same sampling manifold, starting at the same time and ending at the same time 3.24 performance characteristic one of the parameters assigned to equipment in order to define its performance 3.25 performance criterion limiting quantitative numerical value assigned to a performance characteristic, to which conformance is tested 3.26 period of unattended operation time period over which the drift complies with the performance criterion for long term drift 3.27 repeatability (of results of measurement) closeness of the agreement between the results of successive individual measurements of carbon monoxide 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. 3.28 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; SIST EN 14626:2012

EN 14626:2012 (E) 10 c) at the same monitoring station; d) the period of unattended operation. 3.29 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 90 % of the stable output reading 3.30 sampled air part of ambient air that is transferred through the sampling inlet and sampling system for subsequent measurement 3.31 sample gas temperature temperature of the sampled gas at the sample inlet

Note 1 to entry: The term ‘gas’ may refer to a test gas used in type-approval testing or to ambient air transferred to the analyser.

3.32 sampling system the assembly of components needed to transfer ambient air to the analyser 3.33 short-term drift difference between zero or span readings at the beginning and end of a 12 h period 3.34 standard uncertainty uncertainty of the result of a measurement expressed as a standard deviation

[SOURCE: ENV 13005:1999] 3.35 surrounding temperature temperature of the air directly surrounding the analyser 3.36 type approval decision taken by a designated body that the pattern of an analyser conforms to specified requirements

3.37 type approval test examination of two or more analysers of the same pattern which are submitted by a manufacturer to a designated body including the tests necessary for approval of the pattern 3.38 uncertainty (of measurement) parameter associated with the result of a measurement that characterises the dispersion of the values that could reasonably be attributed to the measurand [SOURCE: ENV 13005:1999] 4 Abbreviated terms

FEP
perfluoro-ethylene-propylene MFC mass flow controller SIST EN 14626:2012

EN 14626:2012 (E) 11 PTFE polytetrafluoroethylene 5 Principle 5.1 General This standard describes the method for measurement of the concentration of carbon monoxide in ambient air by means of non-dispersive infrared spectroscopy. The requirements, the specific components of the infrared 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 approval test for which procedures have been described. The type approval test comprises a laboratory test and a field test. The selection of a type-approved analyser for a specific measuring task in the field is based on the calculation of the expanded uncertainty of the measurement method. In this expanded uncertainty calculation, the actual values of various performance characteristics of a type-approved analyser and the site-specific conditions at the monitoring station are taken into account (see 9.6). The expanded uncertainty of the method shall not exceed 15 % for fixed measurements or 25 % for indicative measurements, as 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 The attenuation of infrared light passing through a sample cell is a measure of the concentration of CO in the cell, according to the Lambert-Beer law. Not only CO but also most hetero-atomic molecules will absorb infrared light; in particular water and CO2 have broad bands that can interfere with the measurement of CO. Different technical solutions have been developed to suppress cross-sensitivity, instability and drift in order to design continuous monitoring systems with acceptable properties. For instance:  measuring IR absorption of a specific wavelength (4,7 µm for CO);  dual-cell monitors, using a reference cell filled with clean air (compensation for drift);  gas-filter correlation, “measuring” over a range of wavelengths. Special attention shall be paid to infrared radiation absorbing gases such as water vapour, carbon dioxide, nitrous oxide and hydrocarbons. The concentration of carbon monoxide is measured in volume/volume units (if the analyser is calibrated using a volume/volume standard). The final results for reporting are expressed in mg/m3 using standard conversion factors (see Clause 10). 5.3 Type approval test The type approval test is based on the evaluation of performance characteristics determined under a prescribed series of tests. In this European Standard, test procedures are described for the determination of the actual values of the performance characteristics for at least two analysers in a laboratory and the same analysers in the field, operated in parallel in both cases. The type approval laboratory tests shall not include the sampling inlet, sampling system and external data acquisition system, but shall include analyser sampling line and filter. The type approv

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