SIST EN 16429:2021

Stationary source emissions - Reference method for the determination of the concentration of gaseous hydrogen chloride (HCl) in waste gases emitted by industrial installations into the atmosphere

This document specifies the standard reference method (SRM) based on an automatic method for determination of the mass concentration of hydrogen chloride (HCl) in ducts and stacks emitting to the atmosphere. It describes the sampling and gas conditioning system.
This document specifies the characteristics to be determined and the performance criteria to be fulfilled by portable automated measuring systems (P-AMS) using the infrared measurement method. It applies for periodic monitoring and for the calibration or control of automated measuring systems (AMS) permanently installed on a stack, for regulatory or other purposes.
The infrared measurement method described in this document can be used as a SRM, provided the expanded uncertainty of the method is less than 20 % relative at the daily Emission Limit Value (ELV), or 1 mg/m3 for ELV below 5 mg/m3, and the criteria associated to performance characteristics described in EN 15267-4 for portable automated measuring systems (P-AMS), are fulfilled.
This document specifies criteria for demonstration of equivalence of an alternative method (AM) to the SRM by application of EN 14793.

Emissionen aus stationären Quellen - Referenzverfahren zur Bestimmung der Konzentration von gasförmigem Chlorwasserstoff (HCl) in Abgasen, die von Industrieanlagen in die Atmosphäre emittiert werden

Dieses Dokument legt das auf einem automatischen Verfahren beruhende Standardreferenzverfahren (SRM) zur Bestimmung der Massenkonzentration von Chlorwasserstoff (HCl) in Abgasen, die aus Kanälen und Kaminen in die Atmosphäre emittiert werden, fest. Es legt die Einrichtungen zur Probenahme und Gaskonditionierung fest.
Dieses Dokument legt die zu bestimmenden Eigenschaften und Leistungskriterien fest, die von tragbaren automatischen Messeinrichtungen (en: portable automated measuring system, P-AMS) mit Infrarot-Messverfahren zu erfüllen sind. Es ist anwendbar für die regelmäßige Überwachung und für die Kalibrierung oder Steuerung von dauerhaft an einem Abgaskanal installierten automatischen Messeinrichtungen (en: automated measuring system, AMS) aufgrund regulatorischer oder anderer Gründe.
Das in diesem Dokument festgelegte Infrarot-Messverfahren kann als SRM verwendet werden, sofern die erweiterte Messunsicherheit des Verfahrens weniger als 20 % (relativ) beim 1-Tages-Emissionsgrenzwert (Emission Limit Value, ELV) oder 1 mg/m3 für einen ELV kleiner als 5 mg/m3 beträgt und die Kriterien, die den in EN 15267 4 für tragbare automatische Messeinrichtungen (P-AMS) genannten Leistungskenngrößen zugeordnet sind, erfüllt werden.
Dieses Dokument legt Kriterien für den Nachweis der Gleichwertigkeit eines Alternativverfahrens (en: Alternative Method; AM) mit dem SRM durch Anwendung der EN 14793 fest.

Émissions de sources fixes - Méthode de référence pour la détermination de la concentration de chlorure d’hydrogène gazeux (HCl) dans les effluents gazeux émis dans l’atmosphère par des installations industrielles

Le présent document spécifie la méthode de référence normalisée (SRM) basée sur une méthode automatique de détermination de la concentration massique de chlorure d’hydrogène (HCl) émis dans l’atmosphère par les conduits et les cheminées. Il décrit le système de prélèvement et de conditionnement du gaz.
Le présent document spécifie les caractéristiques devant être déterminées et les critères de performance devant être remplis par les systèmes de mesurage automatisés portables (P-AMS) utilisant la méthode de mesurage infrarouge. Il s’applique à la surveillance périodique ainsi qu’à l’étalonnage ou au contrôle des systèmes de mesurage automatisés (AMS) installés à demeure sur une cheminée, à des fins réglementaires ou autres.
La méthode de mesurage par infrarouge décrite dans le présent document peut servir de SRM, à condition que l’incertitude élargie de la méthode soit inférieure à la valeur relative de 20 % à la valeur limite d’émission (VLE) journalière, ou 1 mg/m3 pour une VLE inférieure à 5 mg/m3, et que les critères associés aux caractéristiques de performance décrites dans l’EN 15267-4 pour les systèmes de mesurage automatisés portables (P-AMS) soient satisfaits.
Le présent document spécifie des critères permettant de prouver l’équivalence d’une méthode alternative (AM) avec la méthode de référence normalisée en appliquant l’EN 14793.

Emisije nepremičnih virov - Referenčna metoda za določevanje koncentracije plinastega vodikovega klorida (HCl) v odpadnih plinih, ki se sproščajo v ozračje iz industrijskih naprav

General Information

• Status: Published
• Public Enquiry End Date: 02-Feb-2020
• Publication Date: 16-Mar-2021
• ICS: 13.040.40 - Stationary source emissions
• Technical Committee: KAZ - Air quality
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 11-Mar-2021
• Due Date: 16-May-2021
• Completion Date: 17-Mar-2021
• Mandate: M/513 - Automatic determination by measurement of the concentration of gaseous hydrogen chloride (HCl) in waste gases emitted by industrial installations into the air
• Ref Project: EN 16429:2021 - Stationary source emissions - Reference method for the determination of the concentration of gaseous hydrogen chloride (HCl) in waste gases emitted by industrial installations into the atmosphere

RELATIONS

• Replaces: SIST-TS CEN/TS 16429:2013 - Stationary source emissions - Sampling and determination of hydrogen chloride content in ducts and stacks - Infrared analytical technique
• Effective Date: 01-May-2021

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN 16429:2021
01-maj-2021
Nadomešča:
SIST-TS CEN/TS 16429:2013
Emisije nepremičnih virov - Referenčna metoda za določevanje koncentracije

plinastega vodikovega klorida (HCl) v odpadnih plinih, ki se sproščajo v ozračje iz

industrijskih naprav
Stationary source emissions - Reference method for the determination of the

concentration of gaseous hydrogen chloride (HCl) in waste gases emitted by industrial

installations into the atmosphere
Emissionen aus stationären Quellen - Referenzverfahren zur Bestimmung der
Konzentration von gasförmigem Chlorwasserstoff (HCl) in Abgasen, die von
Industrieanlagen in die Atmosphäre emittiert werden
Émissions de sources fixes - Méthode de référence pour la détermination de la

concentration de chlorure d’hydrogène gazeux (HCl) dans les effluents gazeux émis

dans l’atmosphère par des installations industrielles
Ta slovenski standard je istoveten z: EN 16429:2021
ICS:
13.040.40 Emisije nepremičnih virov Stationary source emissions
SIST EN 16429:2021 en,fr,de

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

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SIST EN 16429:2021
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SIST EN 16429:2021
EN 16429
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2021
EUROPÄISCHE NORM
ICS 13.040.40 Supersedes CEN/TS 16429:2013
English Version
Stationary source emissions - Reference method for the
determination of the concentration of gaseous hydrogen
chloride (HCl) in waste gases emitted by industrial
installations into the atmosphere

Émissions de sources fixes - Méthode de référence Emissionen aus stationären Quellen -

pour la détermination de la concentration de chlorure Referenzverfahren zur Bestimmung der Konzentration

d'hydrogène gazeux (HCl) dans les effluents gazeux von gasförmigem Chlorwasserstoff (HCl) in Abgasen,

émis dans l'atmosphère par des installations die von Industrieanlagen in die Atmosphäre emittiert

industrielles werden
This European Standard was approved by CEN on 1 February 2021.

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, Turkey 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

© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 16429:2021 E

worldwide for CEN national Members.
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SIST EN 16429:2021
EN 16429:2021 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 5

4 Principle .......................................................................................................................................................... 11

4.1 General ............................................................................................................................................................. 11

4.2 Measuring principle .................................................................................................................................... 12

5 Sampling system ........................................................................................................................................... 12

5.1 General ............................................................................................................................................................. 12

5.2 Sampling probe ............................................................................................................................................. 12

5.3 Filter .................................................................................................................................................................. 12

5.4 Sampling line ................................................................................................................................................. 13

5.5 Conditioning system .................................................................................................................................... 13

5.5.1 Permeation drier (configuration 1) ...................................................................................................... 13

5.5.2 Heated line and heated analyser (configuration 2) ......................................................................... 13

5.6 Sample pump ................................................................................................................................................. 13

5.7 Secondary filter (optional) ....................................................................................................................... 13

6 Analyser equipment .................................................................................................................................... 14

7 Determination of the characteristics of the method: analyser, sampling and

conditioning line .......................................................................................................................................... 14

7.1 General ............................................................................................................................................................. 14

7.2 Relevant performance characteristics of the method and performance criteria ................. 14

7.3 Establishment of the uncertainty budget ............................................................................................ 14

8 Field operation .............................................................................................................................................. 16

8.1 Measurement plan and sampling strategy .......................................................................................... 16

8.2 Setting of the analyser on site .................................................................................................................. 17

8.2.1 General ............................................................................................................................................................. 17

8.2.2 Preliminary zero and span check, and adjustments ....................................................................... 17

8.2.3 Zero and span checks after measurement .......................................................................................... 18

9 Ongoing quality control ............................................................................................................................. 18

9.1 Introduction ................................................................................................................................................... 18

9.2 Frequency of checks .................................................................................................................................... 19

10 Expression of results ................................................................................................................................... 19

11 Equivalence of an alternative method .................................................................................................. 20

12 Measurement report ................................................................................................................................... 20

Annex A (informative) Example of assessment of compliance of non-dispersive infrared

method for HCl with requirements on emission measurements ................................................ 21

Annex B (informative) Example of correction of data from drift effect ................................................ 34

Annex C (informative) Validation of the method in the field .................................................................... 36

Bibliography ................................................................................................................................................................. 42

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SIST EN 16429:2021
EN 16429:2021 (E)
European foreword

This document (EN 16429:2021) 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 September 2021, and conflicting national standards shall

be withdrawn at the latest by September 2021.

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 CEN/TS 16429:2013.
List of significant technical changes compared to CEN/TS 16429:2013:

— Clause 6 "Analyser equipment": The description of the analyser equipment has been replaced by the

reference to performance criteria given in EN 15267-4.

— The informative Annex "Examples of schematics of non-dispersive infrared spectrometer" was

deleted.

— The informative Annex "Validation of the method in the field" was added. EN 16429 has been

validated during field tests on a test bench, on a waste incineration plant and a large combustion

plant for HCl concentrations with sampling periods of 30 min in the range of 2,5 mg/m3 to 61 mg/m3.

The characteristics of installations, the conditions during field tests and the values of repeatability

and reproducibility in the field are given in Annex C.

This document has been prepared under a mandate given to CEN by the European Commission and the

European Free Trade Association.

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, Turkey and the United

Kingdom.
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SIST EN 16429:2021
EN 16429:2021 (E)
Introduction

The European Commission (EC) has charged the European Committee for Standardization (CEN) to

elaborate this new standard (with Mandate M/513 of January 2013). The work was allocated to

CEN/TC 264 “Air quality”/WG 3, who has prepared this document.

This document has been validated during field tests on a test bench, on a waste incineration plant and a

large combustion plant for HCl concentrations with sampling periods of 30 min in the range of 2,5 mg/m

3 3

to 61 mg/m . Directive 2010/75/EU lays down emission values which are expressed in mg/m , on dry

basis at a specified value of oxygen and at standard conditions (273 K and 101,3 kPa).

NOTE The characteristics of installations, the conditions during field tests and the values of repeatability and

reproducibility in the field are given in Annex C.
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SIST EN 16429:2021
EN 16429:2021 (E)
1 Scope

This document specifies the standard reference method (SRM) based on an automatic method for

determination of the mass concentration of hydrogen chloride (HCl) in ducts and stacks emitting to the

atmosphere. It describes the sampling and gas conditioning system.

This document specifies the characteristics to be determined and the performance criteria to be fulfilled

by portable automated measuring systems (P-AMS) using the infrared measurement method. It applies

for periodic monitoring and for the calibration or control of automated measuring systems (AMS)

permanently installed on a stack, for regulatory or other purposes.

The infrared measurement method described in this document can be used as a SRM, provided the

expanded uncertainty of the method is less than 20 % relative at the daily Emission Limit Value (ELV), or

3 3

1 mg/m for ELV below 5 mg/m , and the criteria associated to performance characteristics described in

EN 15267-4 for portable automated measuring systems (P-AMS), are fulfilled.

This document specifies criteria for demonstration of equivalence of an alternative method (AM) to the

SRM by application of EN 14793.
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 14793, Stationary source emissions — Demonstration of equivalence of an alternative method with a

reference method

EN 15259:2007, Air quality — Measurement of stationary source emissions — Requirements for

measurement sections and sites and for the measurement objective, plan and report

EN 15267-3:2007, Air quality — Certification of automated measuring systems — Part 3: Performance

criteria and test procedures for automated measuring systems for monitoring emissions from stationary

sources

EN 15267-4:2017, Air quality — Certification of automated measuring systems — Part 4: Performance

criteria and test procedures for automated measuring systems for periodic measurements of emissions from

stationary sources

EN ISO 14956:2002, Air quality — Evaluation of the suitability of a measurement procedure by comparison

with a required measurement uncertainty (ISO 14956:2002)

CEN/TS 17337, Stationary source emissions — Determination of mass concentration of multiple gaseous

species — Fourier transform infrared spectroscopy

ISO/IEC Guide 98-3:2008, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in

measurement (GUM:1995)
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:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
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EN 16429:2021 (E)
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
[SOURCE: JCGM 200:2012]
3.2
alternative method

measurement method which complies with the criteria given by this document with respect to the

reference method

Note 1 to entry: An alternative method can consist of a simplification of the reference method.

[SOURCE: EN 14793:2017]
3.3
ambient temperature
temperature of the air around the measuring system
3.4
automated measuring system
AMS

entirety of all measuring instruments and additional devices for obtaining a result of measurement

Note 1 to entry: Apart from the actual measuring device (the analyser), an AMS includes facilities for taking

samples (e.g. probe, sample gas lines, flow meters and regulator, delivery pump) and for sample conditioning (e.g.

dust filter, pre-separator for interferents, cooler, converter). This definition also includes testing and adjusting

devices that are required for functional checks and, if applicable, for commissioning.

Note 2 to entry: The term “automated measuring system” (AMS) is typically used in Europe. The term

“continuous emission monitoring system” (CEMS) is also typically used in the UK and USA.

[SOURCE: EN 15267-4:2017]
3.5
calibration

set of operations that establish, under specified conditions, the relationship between values of quantities

indicated by a measuring method or measuring system, and the corresponding values given by the

applicable reference

Note 1 to entry: In case of automated measuring system (AMS) permanently installed on a stack, the applicable

reference is the standard reference method (SRM) used to establish the calibration function of the AMS.

Note 2 to entry: Calibration should not be confused with adjustment of a measuring system.

3.6
drift

difference between two zero (zero drift) or span readings (span drift) at the beginning and at the end of

a measuring period
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EN 16429:2021 (E)
3.7
emission limit value
ELV

emission limit value laid out in EU Directives on the basis of a specified period (e.g. 10 min, 30 min, one

hour, one day…)
3.8
influence quantity

quantity that, in a direct measurement, does not affect the quantity that is actually measured, but affects

the relation between the indication and the measurement result
EXAMPLES
— ambient temperature;
— atmospheric pressure;
— presence of interfering gases in the flue gas matrix;
— pressure of the gas sample.
[SOURCE: JCGM 200:2012, examples have been adapted]
3.9
interference

negative or positive effect that a substance has upon the output of the P-AMS, when that substance is not

the measured component
[SOURCE: EN 15267-4:2017]
3.10
cross-sensitivity
response of the P-AMS to interferents
Note 1 to entry: See interference.
[SOURCE: EN 15267-4:2017]
3.11
lack of fit

systematic deviation, within the measurement range, between the accepted value of a reference material

applied to the measuring system and the corresponding result of measurement produced by the

calibrated measuring system

Note 1 to entry: In common language lack of fit is often called “linearity” or “deviation from linearity”. Lack of fit

test is often called “linearity test”.
[SOURCE: EN 15267-4:2017]
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3.12
measurand
particular quantity subject to measurement

Note 1 to entry: The measurand is a quantifiable property of the stack gas under test, for example mass

concentration of a measured component, temperature, velocity, mass flow, oxygen content and water vapour

content.
[SOURCE: EN 15259:2007]
3.13
measurement method

method described in a written procedure containing all the means and procedures required to sample

and analyse, namely field of application, principle and/or reactions, definitions, equipment, procedures,

presentation of results, other requirements and measurement report
[SOURCE: EN 14793:2017]
3.14
measurement plane
plane normal to the centreline of the duct at the sampling position
Note 1 to entry: Measurement plane is also known as sampling plane.
[SOURCE: EN 15259:2007]
3.15
measurement point

position in the measurement plane at which the sample stream is extracted or the measurement data are

obtained directly
Note 1 to entry: Measurement point is also known as sampling point.
[SOURCE: EN 15259:2007]
3.16
measuring system

set of one or more measuring instruments and often other devices, including any reagent and supply,

assembled and adapted to give information used to generate measured quantity values within specified

intervals for quantities of specified kinds
[SOURCE: JCGM 200:2012]
3.17
performance characteristic
quantity assigned to the P-AMS in order to define its performance

Note 1 to entry: The values of relevant performance characteristics are determined in the performance testing

and compared to the applicable performance criteria.
[SOURCE: EN 15267-4:2017]
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3.18
portable automated measuring system
P-AMS

automated measuring system which is in a condition or application to be moved from one to another

measurement site to obtain measurement results for a short measurement period
Note 1 to entry: The measurement period is typically 8 h for a day.

Note 2 to entry: The P-AMS can be configured at the measurement site for the special application but can be also

set-up in a van or mobile container. The probe and the sample gas lines are installed often just before the

measurement task is started.
[SOURCE: EN 15267-4:2017]
3.19
reference method

measurement method taken as a reference by convention, which gives the accepted reference value of

the measurand
Note 1 to entry: A reference method is fully described.
Note 2 to entry: A reference method can be a manual or an automated method.

Note 3 to entry: Alternative methods may be used if equivalence to the reference method has been demonstrated.

[SOURCE: EN 15259:2007]
3.20
repeatability

condition of measurement, out of a set of conditions that includes the same measurement procedure,

same operators, same measuring system, same operating conditions and same location, and replicable

measurements on the same or similar objects over a short period of time
3.21
repeatability in the field

closeness of the agreement between the results of simultaneous measurements of the same measurand

carried out with two sets of equipment under the same conditions of measurement
Note 1 to entry: These conditions include:
— same measurement method;

— two sets of equipment, the performance of which fulfils the requirements of the measurement method,

used under the same conditions;
— same location;
— implemented by the same laboratory;

— typically calculated on short periods of time in order to avoid the effect of changes of influence

parameters (e.g. 30 min).

Note 2 to entry: Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the

results.

Note 3 to entry: In this document, the repeatability under field conditions is expressed as a value with a level of

confidence of 95 %.
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3.22
reproducibility in the field

closeness of the agreement between the results of simultaneous measurements of the same measurand

carried out using several sets of equipment under the same conditions of measurement

Note 1 to entry: These conditions are called field reproducibility conditions and include:

— same measurement method;

— several sets of equipment, the performance of which are fulfilling the requirements of the measurement

method, used under the same conditions;
— same location;
— implemented by several laboratories.

Note 2 to entry: Reproducibility may be expressed quantitatively in terms of the dispersion characteristics of the

results.

Note 3 to entry: In this document, the reproducibility under field conditions is expressed as a value with a level

of confidence of 95 %.
3.23
residence time in the measuring system

time period for the sampled gas to be transported from the inlet of the probe to the inlet of the

measurement cell
3.24
response time

time interval between the instant of a sudden change in the value of the input quantity to an AMS and the

time as from which the value of the output quantity is reliably maintained above 90 % of the correct value

of the input quantity
Note 1 to entry: The response time is also referred to as the 90 % time.
[SOURCE: EN 15267-3:2007]
3.25
span gas

test gas used to adjust and check a specific point on the response line of the measuring system

Note 1 to entry: This concentration is often chosen around 80 % of the upper limit of the range or around the

emission limit value.
3.26
standard reference method
SRM
reference method prescribed by European or national legislation
[SOURCE: EN 15259:2007]
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3.27
uncertainty

parameter associated with the result of a measurement, that characterises the dispersion of the values

that could reasonably be attributed to the measurand
[SOURCE: ISO/IEC Guide 98-3:2008]
3.28
standard uncertainty
uncertainty of the result of a measurement expressed as a standard deviation u
[SOURCE: ISO/IEC Guide 98-3:2008]
3.29
combined standard uncertainty

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

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

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

varies with changes in these quantities
[SOURCE: ISO/IEC Guide 98-3:2008]
3.30
expanded uncertainty

quantity defining a level of confidence about the result of a measurement that could be expected to

encompass a specific fraction of the distribution of values that could reasonably be attributed to a

measurand
[SOURCE: ISO/IEC Guide 98-3:2008]

Note 1 to entry: The interval about the result of measurement is established for a level of confidence of 95 %.

3.31
uncertainty budget

statement of a measurement uncertainty, of the components of that measurement uncertainty, and of

their calculation and combination
[SOURCE: JCGM 200:2012; Note 1 added]

Note 1 to entry: Calculation table combining all the sources of uncertainty according to EN ISO 14956 or

ISO/IEC Guide 98-3:2008.
4 Principle
4.1 General

This document specifies a method for the determination of the mass concentration of hydrogen chloride

(HCl) in ducts and stacks emitting to atmosphere by means of an automatic analyser using the infrared

absorption principle. The specific components and requirements for the sampling system and the

infrared analyser are described in Clause 5 and 6. A number of performance characteristics with

associated minimum performance criteria and an expanded uncertainty of the method are given.

Requirements and recommendations for quality assurance and quality control are given for

measurements in the field (see Table 1 in 7.3).
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4.2 Measuring principle

The HCl concentration is measured with an infrared absorption method. The attenuation of infrared light

passing through a sample cell is a measure of the concentration of HCl in the cell, according to the

Lambert-Beer law. Not only HCl but also most hetero-atomic molecules absorb infrared light, in particular

water and CO have broad bands that can interfere with the measurement of HCl. Different technical

solutions have been developed to suppress cross-sensitivity, instability and drift in order to design

automatic monitoring systems with acceptable properties. For instance: Gas Filter Correlation, Tunable

Diode Laser (TDL) and Fourier Transform Infrared Spectroscopy (FTIR).

The P-AMS will be used only in the field of gas matrices tested during its characterization according to

EN 15267-4.

Infrared analysers are part of extractive or in situ systems. Most of them are combined with an extractive

sampling system and a gas conditioning system. A representative sample of gas is taken from the stack

with a sampling probe and conveyed to the analyser through the sampling line and gas conditioning

system. The values from the analyser are recorded and/or stored by means of electronic data processing.

The concentration of HCl is typically measured in parts per million by volume (ppmv). The final results

for reporting are expressed in milligrams per cubic meter using standard conversion factors (see

Clause 10).
5 Sampling system
5.1 General

A volume is extracted (see 8.2.1) from the flue gas for a fixed period of time at a controlled flow rate. A

filter removes the dust in the sampled volume before the sample is conditioned and passes to the

analyser. Two different sampling and conditioning configurations can be used in order to avoid

uncontrolled water vapour condensation in the measuring system. These configurations are:

— configuration 1: removal of water vapour through elimination using a permeation drier;

— configuration 2: maintaining the temperature of the sampling line at a minimum value (see 5.5.2) up

to the heated analyser.

Conditions and layout of the sampling equipment contribute to the expanded uncertainty. In order to

minimize this contribution to the expanded uncertainty of the method, sampling conditions are given in

...