SIST EN 14789:2005

Stationary source emissions - Determination of volume concentration of oxygen (O2) - Reference method - Paramagnetism

This European Standard describes the paramagnetic method, including the sampling and the gas conditioning system, to determine the oxygen concentrations in flue gases emitted to the atmosphere from ducts and stacks.
This European Standard is the Standard Reference Method (SRM) for periodic monitoring and for the calibration or control of Automatic Measuring Systems (AMS) permanently installed on a stack, for regulatory purposes or other purposes. To be used as the SRM, the user shall demonstrate that the performance characteristics of the method are better than the performance criteria defined in this European Standard and that the overall uncertainty of the method is less than ± 6,0 percent of the measured concentration.
NOTE   When paramagnetism is the measurement principle used for AMS, reference should be made to EN 14181 and other relevant standards provided by CEN/TC 264.
An alternative method to this SRM may be used provided that the user can demonstrate equivalence according to the Technical Specification CEN/TS 14793, to the satisfaction of his national accreditation body or law.
This Standard Reference Method has been evaluated during field tests on waste incineration, co-incineration and large combustion installations. It has been validated for sampling periods of 30 min in the range: 5 percent to 26 percent. Oxygen concentration values, expressed in percent volume, are used in order to allow emission measurements of pollutants to be standardised to the reference O2 concentration and dry gas conditions required by the following Council Directives:
   Council Directive 2001/80/EC on the limitation of emissions of certain pollutants into the air from large combustion plants;
   Council Directive 2000/76/EC on waste incineration plants.

Emissionen aus stationären Quellen - Bestimmung der Volumenkonzentration von Sauerstoff (O2) - Referenzverfahren - Paramagnetismus

Diese Europäische Norm beschreibt das paramagnetische Verfahren einschließlich der Probenahme und des Gasvorbehandlungssystems zur Bestimmung der Sauerstoffkonzentrationen in Abgasen, die aus Abgaskanälen in die Atmosphäre emittiert werden.
Diese Europäische Norm ist das Standardreferenzverfahren (SRM) für die periodische Überwachung und für die Kalibrierung oder Überprüfung von automatischen Messsystemen (AMS), die aus gesetzgeberischen oder anderen Gründen permanent an einem Abgaskanal installiert sind. Damit dieses Verfahren als Standardreferenzverfahren angewandt werden kann, muss der Anwender nachweisen, dass die Verfahrenskenngrößen besser sind als die Leistungskriterien in dieser Norm und dass die Gesamtmessunsicherheit des Verfahrens kleiner ist als ± 6 % der gemessenen Konzentration.
ANMERKUNG   Wenn der Paramagnetismus als Messprinzip eines automatischen Messsystems genutzt wird, sollte auf EN 14181 und andere einschlägige Normen des CEN/TC 264 Bezug genommen werden.
Ein anderes als dieses Standardreferenzverfahren darf angewendet werden, wenn der Anwender vor der nationalen Akkreditierungsstelle oder dem Gesetz die Äquivalenz nach der Technischen Spezifikation CEN/TS 14793 nachweisen kann.
Dieses Standardreferenzverfahren wurde während Feldversuchen an Abfallverbrennungsanlagen und Mitverbrennungsanlagen sowie an Großfeuerungsanlagen erprobt. Sie wurde mit Probenahmedauern von 30 min im Bereich von 5 % bis 26 % validiert. O2-Konzentrationswerte, angegeben als Volumenanteil, werden verwendet, um die Ergebnisse von Emissionsmessungen von Schadstoffen auf die O2-Bezugskonzentration und auf trockenes Gas zu beziehen, wie von den folgenden Richtlinien des Rates gefordert wird:
-   Richtlinie 2001/80/EG des Europäischen Parlaments und des Rates vom 23. Oktober 2001 zur Begrenzung von Schadstoffemissionen von Großfeuerungsanlagen in die Luft;
Richtlinie 2000/76/EG des Europäischen Parlaments und des Rates vom 4. Dezember 2000 über die Verbrennung von Abfällen.

Emissions de sources fixes - Détermination de la concentration volumique en oxygene (O2) - Méthode de référence: Paramagnétisme

La présente Norme européenne décrit la méthode paramagnétique comprenant le systeme de prélevement et
de conditionnement du gaz, afin de déterminer les concentrations en oxygene présentes dans les effluents
gazeux émis dans l’atmosphere par les conduits et cheminées.
La présente Norme européenne est la méthode de référence normalisée (SRM) en matiere de surveillance
périodique et d’étalonnage ou de contrôle des systemes automatiques de mesurage (AMS) installés a
demeure sur une cheminée, a des fins réglementaires ou autres. Pour utiliser la norme comme SRM,
l’utilisateur doit démontrer que les caractéristiques de performance de la méthode sont meilleures que les
criteres de performance définis dans la présente Norme européenne et que l’incertitude globale de la
méthode est inférieure a ± 6,0 % de la concentration mesurée.
NOTE Lorsque le paramagnétisme est utilisé comme principe de mesurage pour l’AMS, consulter l’EN 14181 et les
autres normes pertinentes élaborées par le CEN/TC 264.
Il est possible d’employer une méthode différente a condition que l’utilisateur puisse démontrer son
équivalence selon la spécification technique de la CEN/TS 14793 et en accord avec son organisme
d’accréditation national ou la loi.
Cette méthode de référence normalisée a été évaluée au cours d’essais sur site pratiqués sur les installations
destinées a l’incinération des déchets, la coincinération et sur des grandes installations de combustion. Elle a
été validée pour des périodes de prélevement de 30 min dans la plage comprise entre : 5 % et 26 %. Les
valeurs de concentration en oxygene, exprimées en pourcentage volumique, sont utilisées afin d’exprimer les
résultats des mesurages d’émission des polluants aux conditions de référence en O 2 et aux conditions de gaz
sec requises par les Directives du Conseil suivantes :

Emisije nepremičnih virov - Določevanje volumske koncentracije kisika (O2) – Referenčna metoda – Paramagnetizem

General Information

• Status: Withdrawn
• Publication Date: 30-Nov-2005
• Withdrawal Date: 31-Jan-2017
• ICS: 13.040.40 - Stationary source emissions
• Technical Committee: KAZ - Air quality
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 27-Jan-2017
• Due Date: 19-Feb-2017
• Completion Date: 01-Feb-2017
• Directive: 88/609/EEC - Limitation of emissions of certain pollutants into the air from large combustion plants
• Directive: 89/369/EEC - Prevention of air pollution from new municipal waste incineration plants
• Directive: 89/429/EEC - Reduction of air pollution from existing municipal waste incineration plants
• Directive: 94/67/EC - Incineration of hazardous waste
• Mandate: M/277 - Standardization mandate to CEN for manual reference methods for the calibration of automated measurement systems for oxygen (02) and water vapour (H2O) emissions in stack
• Ref Project: EN 14789:2005 - Stationary source emissions - Determination of volume concentration of oxygen (O2) - Reference method - Paramagnetism

Relations

• Replaced By: SIST EN 14789:2017 - Stationary source emissions - Determination of volume concentration of oxygen - Standard reference method: Paramagnetism
• Effective Date: 01-Mar-2017

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 14789:2005
01-december-2005
(PLVLMHQHSUHPLþQLKYLURY'RORþHYDQMHYROXPVNHNRQFHQWUDFLMHNLVLND2±
5HIHUHQþQDPHWRGD±3DUDPDJQHWL]HP
Stationary source emissions - Determination of volume concentration of oxygen (O2) -
Reference method - Paramagnetism
Emissionen aus stationären Quellen - Bestimmung der Volumenkonzentration von
Sauerstoff (O2) - Referenzverfahren - Paramagnetismus
Emissions de sources fixes - Détermination de la concentration volumique en oxygene
(O2) - Méthode de référence: Paramagnétisme
Ta slovenski standard je istoveten z: EN 14789:2005
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
SIST EN 14789:2005 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 14789:2005

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SIST EN 14789:2005
EUROPEAN STANDARD
EN 14789
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2005
ICS 13.040.40

English Version
Stationary source emissions - Determination of volume
concentration of oxygen (O2) - Reference method -
Paramagnetism
Emissions de sources fixes - Détermination de la Emissionen aus stationären Quellen - Bestimmung der
concentration volumique en oxygène (O2) - Méthode de Volumenkonzentration von Sauerstoff - Referenzverfahren -
référence: Paramagnétisme Paramagnetismus
This European Standard was approved by CEN on 30 September 2005.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14789:2005: E
worldwide for CEN national Members.

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SIST EN 14789:2005
EN 14789:2005 (E)
Contents Page
Foreword .4
1 Scope.5
2 Normative references.5
3 Terms and definitions.5
4 Principle.10
4.1 General.10
4.2 Measuring principle.10
5 Description of measuring equipment - Sampling and sample gas conditioning systems.10
5.1 General.10
5.2 Sampling line components.11
5.2.1 Sampling line.11
5.2.2 Filter.11
5.2.3 Sample cooler or permeation drier.11
5.2.4 Sample pump.11
5.2.5 Secondary filter.12
5.2.6 Flow controller and flow meter .12
6 Analyser equipment.12
7 Determination of the characteristics of the SRM : analyser, sampling and conditioning

line.13
7.1 General.13
7.2 Relevant performance characteristics of the SRM and performance criteria .13
7.3 Establishment of the uncertainty budget.14
8 Field operation.15
8.1 Sampling location.15
8.2 Sampling point(s).15
8.3 Choice of the measuring system .16
8.4 Setting of the SRM on site.16

8.4.1 General.16
8.4.2 Preliminary zero and span check, and adjustments .17
8.4.3 Zero and span checks after measurement.17
9 Ongoing quality control.18
9.1 General.18
9.2 Frequency of checks .18
10 Expression of results.18
11 Evaluation of the method in the field.18
12 Equivalence with an alternative method .19
13 Test report.19
(informative)
Annex A Schematic diagram of the measurement system .21
Annex B (informative) Example of assessment of compliance of paramagnetic method for O with
2
requirements on emission measurements.22
B.1 Process of uncertainty estimation.22

B.1.1 General.22
B.1.2 Determination of model function .22
B.1.3 Quantification of uncertainty components .22
B.1.4 Calculation of the combined uncertainty .22
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EN 14789:2005 (E)
B.2 Specific conditions in the site.23
B.3 Performance characteristics of the method .24
B.4 Calculation of the standard uncertainty of the concentration values given by the analyser.25
B.4.1 Model equation and application of the rule of the uncertainty propagation .25

B.4.2 Calculation of the partial uncertainties .26
B.4.3 Results of uncertainty calculation.31
Annex C (informative) Procedure of correction of data from drift effect .33
Annex D (informative) Evaluation of the method in the field .34
D.1 General.34
D.2 Characteristics of installations.34
D.3 Repeatability and reproducibility in the field.35
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive.38
Bibliography.39

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SIST EN 14789:2005
EN 14789:2005 (E)
Foreword
This European Standard (EN 14789:2005) 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 May 2006, and conflicting national standards shall be withdrawn at the
latest by May 2006.
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association, and supports essential requirements of EU Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this European
Standard.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland
and United Kingdom.
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SIST EN 14789:2005
EN 14789:2005 (E)
1 Scope
This European Standard describes the paramagnetic method, including the sampling and the gas conditioning
system, to determine the oxygen concentrations in flue gases emitted to the atmosphere from ducts and
stacks.
This European Standard is the Standard Reference Method (SRM) for periodic monitoring and for the
calibration or control of Automatic Measuring Systems (AMS) permanently installed on a stack, for regulatory
purposes or other purposes. To be used as the SRM, the user shall demonstrate that the performance
characteristics of the method are better than the performance criteria defined in this European Standard and
that the overall uncertainty of the method is less than ± 6,0 % of the measured concentration.
NOTE When paramagnetism is the measurement principle used for AMS, reference should be made to EN 14181
and other relevant standards provided by CEN/TC 264.
An alternative method to this SRM may be used provided that the user can demonstrate equivalence
according to the Technical Specification CEN/TS 14793, to the satisfaction of his national accreditation body
or law.
This Standard Reference Method has been evaluated during field tests on waste incineration, co-incineration
and large combustion installations. It has been validated for sampling periods of 30 min in the range: 5 % to
26 %. Oxygen concentration values, expressed in % volume, are used in order to allow emission
measurements of pollutants to be standardised to the reference O concentration and dry gas conditions
2
required by the following Council Directives:
 Council Directive 2001/80/EC on the limitation of emissions of certain pollutants into the air from large
combustion plants;
 Council Directive 2000/76/EC on waste incineration plants.
2 Normative references
The following referenced documents are indispensable for the application 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.
CEN/TS 14793, Stationary source emission – Intralaboratory validation procedure for an alternative method
compared to a reference method.
ENV 13005, Guide to the expression of uncertainty in measurement.
EN ISO 14956, Air quality - Evaluation of the suitability of a measurement procedure by comparison with a
required measurement uncertainty (ISO 14956:2002).
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
NOTE In this European Standard, the concentration of O is expressed in % volume.
2
3.1
adjustment (of a measuring system)
operation of bringing a measuring system into a state of performance suitable for its use
[VIM 4.30]
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EN 14789:2005 (E)
3.2
ambient temperature
temperature of the air around the measuring device
3.3
automatic measuring system (AMS)
measuring system permanently installed on site for continuous monitoring of emissions
NOTE 1 An AM is a method which is traceable to a reference method.
NOTE 2 Apart from the analyser, an AMS includes facilities for taking samples (e.g. probe, sample gas lines, flow
meters, regulators, delivery pumps) and for sample conditioning (e.g. dust filter, moisture removal devices, converters,
diluters). This definition also includes testing and adjusting devices, that are required for regular functional checks.
[EN 14181]
3.4
calibration
statistical relationship between values of the measurand indicated by the measuring system (AMS) and the
corresponding values given by the standard reference method (SRM) used during the same period of time
and giving a representative measurement on the same sampling plane
NOTE The result of calibration permits to establish the relationship between the values of the SRM and the AMS
(calibration function).
3.5
drift
difference between two zero (zero drift) or span readings (span drift) at the beginning and at the end of a
measuring period
3.6
emission limit value (ELV)
emission limit value according to EU Directives on the basis of 30 min, 1 hour or 1 day
3.7
influence quantity
quantity that is not the measurand but that affects the result of the measurement
[adapted VIM 2.7]
NOTE Examples:
 ambient temperature;
 atmospheric pressure;
 presence of interfering gases in the flue gas matrix;
 pressure of the gas sample.
3.8
interference
negative or positive effect upon the response of the measuring system, due to a component of the sample that
is not the measurand
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EN 14789:2005 (E)
3.9
lack of fit
systematic deviation within the range of application between the measurement result obtained by applying the
calibration function to the observed response of the measuring system measuring test gases and the
corresponding accepted value of such test gases
NOTE 1 Lack of fit may be a function of the measurement result.
NOTE 2 The expression "lack of fit" is often replaced in everyday language by "linearity" or "deviation from linearity".
3.10
measurand
particular quantity subject to measurement
[VIM 2.6]
3.11
measuring system
complete set of measuring instruments and other equipment assembled to carry out specified measurements
[VIM 4.5]
3.12
performance characteristic
one of the quantities (described by values, tolerances, range) assigned to equipment in order to define its
performance
3.13
repeatability in the laboratory
closeness of the agreement between the results of successive measurements of the same measurand carried
out under the same conditions of measurement
NOTE 1 Repeatability conditions include:
 same measurement procedure;
 same laboratory;
 same measuring instrument, used under the same conditions;

same location;
 repetition over a short period of time.
NOTE 2 Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard the repeatability is expressed as a value with a level of confidence of 95 %.
[VIM 3.6]
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3.14
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 These conditions include:
 same measurement procedure;
 two sets of equipment, the performances of which are fulfilling the requirements of the reference 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 Repeatability may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard, the repeatability under field conditions is expressed as a value with a level of
confidence of 95 %.
3.15
reproducibility in the field
closeness of the agreement between the results of simultaneous measurements of the same measurand
carried out with several sets of equipment under the same conditions of measurement
NOTE 1 These conditions are called field reproducibility conditions and include:
 same measurement procedure;
 several sets of equipment, the performances of which fulfil the requirements of the reference method, used under the
same conditions;
 same location;
 implemented by several laboratories.
NOTE 2 Reproducibility may be expressed quantitatively in terms of the dispersion characteristics of the results.
In this European Standard, the reproducibility under field conditions is expressed as a value with a level of
confidence of 95 %.
3.16
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
3.17
response time
time interval between the instant when a stimulus is subjected to a specified abrupt change and the instant
when the response reaches and remains within specified limits around its final steady value
NOTE By convention time taken for the output signal to pass from 0 % to 90 % of the final change.
[VIM 5.17]
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EN 14789:2005 (E)
3.18
sampling location
specific area, close to the sampling plane, where the measurement devices are set up
3.19
sampling plane
plane normal to the centreline of the duct at the sampling position
[EN 13284-1]
3.20
sampling point
specific position on a sampling line at which a sample is extracted
[EN 13284-1]
3.21
span gas
test gas used to adjust and check a specific point on the response line of the measuring system
NOTE This concentration is often chosen around 80 % of the upper limit of the range.
3.22
Standard Reference Method (SRM)
measurement method recognised by experts and taken as a reference by convention, which gives, or is
presumed to give, the accepted reference value of the concentration of the measurand (3.10) to be measured
3.23
uncertainty
parameter associated with the result of a measurement, that characterises the dispersion of the values that
could reasonably be attributed to the measurand
3.23.1
standard uncertainty u
uncertainty of the result of a measurement expressed as a standard deviation u
3.23.2
combined uncertainty u
c
standard uncertainty u attached to the measurement result calculated by combination of several standard
c
uncertainties according to GUM
3.23.3
expanded uncertainty U
quantity defining a level of confidence about the result of a measurement that may be expected to encompass
a specific fraction of the distribution of values that could reasonably be attributed to a measurand
U = k x u
NOTE In this European Standard, the expanded uncertainty is calculated with a coverage factor of k=2, and
with a level of confidence of 95 %.
3.23.4
overall uncertainty U
c
expanded combined standard uncertainty attached to the measurement result calculated according to GUM
U = k x u
c c
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EN 14789:2005 (E)
3.24
uncertainty budget
calculation table combining all the sources of uncertainty according to EN ISO 14956 or ENV 13005 in order
to calculate the overall uncertainty of the method at a specified value
4 Principle
4.1 General
This European Standard describes the Standard Reference Method (SRM), based on the paramagnetism
principle for sampling and determining oxygen O concentration in flue gases emitted to atmosphere from
2
ducts and stacks. The specific components and the requirements for the sampling system and the
paramagnetic analyser are described. A number of performance characteristics, together with associated
minimum performance criteria are specified for the analyser. These performance characteristics and the
overall uncertainty of the method shall meet the performance criteria given in this European Standard.
Requirements and recommendations for quality assurance and quality control are given for measurements in
the field (see Table 1 in 7.2).
4.2 Measuring principle
The paramagnetic method is based on the principle that oxygen molecules are strongly attracted to a
magnetic field. This property, known as paramagnetism, can be used for the selective measurement of
oxygen in flue gases where the other constituents are either slightly or non-paramagnetic. The magnetic
susceptibility or degree of magnetisation produced in a gas sample by a magnetic field is inversely
proportional to its absolute temperature. A gas sample containing oxygen, when exposed to the combined
effect of a magnetic gradient in a confined space, shall be constrained to flow in the direction of the magnetic
field. The magnitude of this flow, other factors being equal, is dependent on the oxygen concentration in the
gas sample induced flow. A number of devices, described in clause 6 have been developed to measure the
paramagnetically induced flow.
Paramagnetic analysers 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 a sampling line and suitable gas conditioning system. The values from the analyser are recorded
and/or stored by means of electronic data processing.
5 Description of measuring equipment - Sampling and sample gas conditioning
systems
5.1 General
A representative volume of flue gas (see 8.2) is extracted from the emission source for a fixed period of time
at a controlled flow rate. A filter removes the dust in the sampled volume before the sampled gas is
conditioned and passed to the analyser.
Two different sampling and conditioning configurations are available in order to avoid uncontrolled water
condensation in the measuring system. Both approaches require that the user shall check that the dew point
temperature is lower or equal to 4 °C at the outlet of the analyser. The user may correct the results for the
remaining water content in order to report results on a dry basis (refer to the table of Annex A in
EN 14790:2003).
These configurations are:
 configuration 1: removal of water vapour by condensation using a cooling system;
 configuration 2: removal of water vapour through elimination within a permeation drier.
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EN 14789:2005 (E)
Schematic diagrams of typical measuring systems are shown in Annex A.
It is important that all parts of the sampling equipment upstream of the analyser are made of materials that do
not react with or absorb O . Except for the cooling system of configuration 1, the temperature of its
2
components coming into contact with the gas, shall be maintained at a sufficiently high temperature to avoid
any condensation.
Conditions and layout of the sampling equipment contribute to the overall uncertainty of the measurement. In
order to minimise this contribution to the overall measurement uncertainty, the performance criteria for the
sampling equipment and sampling conditions are given in sections 5.2 and 6.
5.2 Sampling line components
5.2.1 Sampling line
In order to access the representative measurement point(s) of the sampling plane, probes of different lengths
and inner diameters may be used. The design and configuration of the probe used shall ensure the residence
time of the sample gas within the probe is minimised in order to reduce the response time of the measuring
system.
The procedure of sub-clause 8.2 shall be used when the operator suspects that the flue gas is
inhomogeneous.
The probe may be marked before sampling in order to demonstrate that the representative measurement
point(s) in the measurement plane has (have) been reached.
The line shall be made of a suitable, corrosion resistant material (e.g. stainless steel, borosilicate glass,
ceramic, titanium, PTFE is only suitable for flue gas temperatures lower than 200 °C).
A seal-able connection may be installed on the probe in order to introduce test gases for adjustment.
5.2.2 Filter
The particle filter shall be made of an inert material (e.g. ceramic or sinter metal filter with an appropriate pore
size). It shall be heated above the water or acid dew point. The particle filter shall be changed or cleaned
periodically depending on the dust loading at the sampling site.
NOTE Overloading of the particle filter may increase the pressure drop in the sampling line.
5.2.3 Sample cooler or permeation drier
The sample cooler or permeation drier is used before the gas enters the analyser in order to separate water
vapour from the flue gas. A maximum dew-point temperature of 4 °C shall not be exceeded at the outlet of the
system.
NOTE The measured oxygen concentration, given by these sampling configurations, can be considered to be dry.
However, the user may correct the results for the remaining water (refer to the Table of Annex A in EN 14790:2003).
5.2.4 Sample pump
When a pump is not an integral part of the paramagnetic analyser, an external pump is necessary to draw the
sampled air through the apparatus. It shall be capable of operating according to the specified flow
requirements of the manufacturer of the analyser and pressure conditions required for the reaction chamber.
The pump shall be resistant to corrosion and consistent with the requirements of the analyser to which it is
connected.
NOTE The quantity of sample gas required can vary between 15 l/h and 500 I/h, depending upon the analyser and
the expected response time.
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EN 14789:2005 (E)
5.2.5 Secondary filter
The secondary filter is used to separate fine dust, with a pore size of 1 µm to 2 µm. It may be made in glass-
fibre, sintered ceramic, stainless steel or PTFE.
NOTE No additional secondary filter is necessary when they are part of the analyser itself.
5.2.6 Flow controller and
...