Ambient Air Quality - Standard method for the determination of the concentration of ammonia by diffusive sampling

This European Standard specifies a method for the sampling and analysis of NH3 in ambient air using
diffusive sampling.
It can be used for NH3 measurements at ambient levels but the concentration range and exposure time are sampler dependent and the end user shall use the working conditions for the various devices as recommended by the manufacturer.
Denuders may be used as a surrogate reference method, and for this reason their use is also described in this European Standard.

Außenluftqualität - Messverfahren zur Bestimmung der Konzentration von Ammoniak mit Passivsammlern

Dieses Dokument legt ein Verfahren zur Probenahme und Analyse von NH3 in Außenluft mit Passivsammlern fest.
Es kann für NH3 Messungen bei Außenluftkonzentrationen verwendet werden; Konzentrationsbereich und Expositionszeit sind aber sammlerabhängig. Dem Anwender wird daher empfohlen, einen den Messanforderungen entsprechenden Sammlertyp zu wählen und sich an die Herstellerangaben zu halten.

Air ambiant - Méthode normalisée pour la détermination de la concentration d'ammoniac au moyen d'échantillonneurs par diffusion

Le présent document spécifie une méthode pour l’échantillonnage et l’analyse du NH3 dans l’air ambiant à l’aide d’échantillonneurs par diffusion.
Elle peut être utilisée pour mesurer le NH3 aux niveaux ambiants, mais la gamme de concentrations et la durée d’exposition dépendent de l’échantillonneur. Il est donc conseillé à l’utilisateur final d’adapter le type d’échantillonneur aux exigences de mesure et de se conformer aux instructions d’utilisation fournies par le fabricant.

Kakovost zunanjega zraka - Standardna metoda za določevanje koncentracije amoniaka z difuzijskim vzorčenjem

General Information

Status
Published
Public Enquiry End Date
03-Apr-2019
Publication Date
08-Jun-2020
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
05-Jun-2020
Due Date
10-Aug-2020
Completion Date
09-Jun-2020

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SLOVENSKI STANDARD
SIST EN 17346:2020
01-julij-2020
Kakovost zunanjega zraka - Standardna metoda za določevanje koncentracije
amoniaka z difuzijskim vzorčenjem

Ambient Air Quality - Standard method for the determination of the concentration of

ammonia by diffusive sampling

Außenluftqualität - Messverfahren zur Bestimmung der Konzentration von Ammoniak mit

Passivsammlern

Air ambiant - Méthode normalisée pour la détermination de la concentration d'ammoniac

au moyen d'échantillonneurs par diffusion
Ta slovenski standard je istoveten z: EN 17346:2020
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
SIST EN 17346:2020 en,fr,de

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

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SIST EN 17346:2020
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SIST EN 17346:2020
EN 17346
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2020
EUROPÄISCHE NORM
ICS 13.040.20
English Version
Ambient air - Standard method for the determination of
the concentration of ammonia using diffusive samplers

Air ambiant - Méthode normalisée pour la Außenluft - Messverfahren zur Bestimmung der

détermination de la concentration en ammoniac au Konzentration von Ammoniak mit Passivsammlern

moyen d'échantillonneurs par diffusion
This European Standard was approved by CEN on 13 April 2020.

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

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 17346:2020 E

worldwide for CEN national Members.
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SIST EN 17346:2020
EN 17346:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 4

Introduction .................................................................................................................................................................... 5

1 Scope .................................................................................................................................................................... 9

2 Normative references .................................................................................................................................... 9

3 Terms and definitions ................................................................................................................................... 9

4 Description of samplers ............................................................................................................................. 11

4.1 Principle .......................................................................................................................................................... 11

4.2 Implementation ............................................................................................................................................ 11

4.3 Tube-type samplers..................................................................................................................................... 11

4.4 Badge-type samplers .................................................................................................................................. 12

4.5 Radial samplers ............................................................................................................................................ 12

5 Calculation of the concentration of NH ............................................................................................... 12

5.1 Mass concentration ..................................................................................................................................... 12

5.2 Conversion to standard conditions of temperature and pressure ............................................. 13

6 Quality control/quality assurance ......................................................................................................... 13

6.1 Quality control .............................................................................................................................................. 13

6.2 Quality assurance ......................................................................................................................................... 14

7 Report ............................................................................................................................................................... 14

8 Performance requirements and measurement uncertainty ........................................................ 15

Annex A (informative) Tube-type samplers .................................................................................................... 16

A.1 Sampler design .............................................................................................................................................. 16

A.2 Extraction and analysis .............................................................................................................................. 16

A.3 Application range and conditions .......................................................................................................... 16

Annex B (informative) Badge-type samplers .................................................................................................. 18

B.1 Type 1 badge-type sampler ...................................................................................................................... 18

B.2 Type 2 badge-type sampler ...................................................................................................................... 20

B.3 Type 3 badge-type sampler ...................................................................................................................... 23

B.4 Type 4 badge-type sampler ...................................................................................................................... 25

Annex C (informative) Radial samplers ............................................................................................................ 29

C.1 Sampler design .............................................................................................................................................. 29

C.2 Extraction and analysis .............................................................................................................................. 30

C.3 Application range and conditions .......................................................................................................... 31

Annex D (informative) Summary of passive diffusive sampling rate data ........................................... 32

Annex E (normative) Estimation of the sampling rate of the samplers ................................................. 33

Annex F (informative) Measurement uncertainty calculation ................................................................. 35

F.1 Measurement equation .............................................................................................................................. 35

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SIST EN 17346:2020
EN 17346:2020 (E)

F.2 Combined standard uncertainty ............................................................................................................. 35

F.3 Expanded relative uncertainty ................................................................................................................ 36

F.4 Uncertainty contributions ......................................................................................................................... 36

Bibliography ................................................................................................................................................................. 41

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SIST EN 17346:2020
EN 17346:2020 (E)
European foreword

This document (EN 17346:2020) 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 November 2020, and conflicting national standards shall

be withdrawn at the latest by November 2020.

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.

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 17346:2020
EN 17346:2020 (E)
Introduction

Atmospheric ammonia (NH ) is a pollutant of major environmental concern with adverse effects on

forests, species composition of semi-natural ecosystems and soils [1-4]. Emission and deposition of NH

can contribute significantly to total nitrogen deposition to the environment, contributing to

eutrophication (nutrient enrichment) and acidification (oxidation of NH to nitrate resulting in release of

H ions) of land and freshwaters, leading to a reduction in both soil and water quality, loss of biodiversity

and ecosystem change [5-10].

In addition to these effects, NH3 is the major precursor for neutralization of atmospheric acids, affecting

the long-range transport distance of both SO and NO and leading to the formation of secondary particles

2 x

(primarily ammonium sulphate and ammonium nitrate) [11-13]. These particles have multiple impacts

including effects on atmospheric visibility, radiative scattering (and the greenhouse effect) and on human

health.

The recognition of NH as an important air pollutant led to its inclusion in international agreements to

reduce air pollutant emissions, first under the 1999 UNECE Gothenburg Protocol and then the National

Emissions Ceilings Directive (NECD) (2001/81/EC) of the EU. The target of both these agreements is that

NH emissions should not exceed emission ceilings set for EU member states, with a particular focus on

reducing the extent of critical loads exceedance for acidification and eutrophication effects. Revision of

the Gothenburg Protocol (2012) and the NEC Directive (2016) include new, more stringent emission

ceilings for 2020 that seek more environmental protection and improvement in air quality than has so

far been committed, including the introduction of an emissions ceiling for particulate matter (PM). Under

the 2012 UNECE Gothenburg Protocol, EU member states have to jointly cut their emissions of NH by

6 % and particles by 22 % between 2005 and 2020. As a precursor of PM, controlling NH is important to

reducing particle emissions of PM and PM . A recent study employing three chemical transport models

2,5 10

found that the models underestimated the formation of ammonium particles and concluded that the role

of NH on PM is larger than originally thought [14]. Thus the implementation of 2020 targets detailed

above may not be enough to deliver compliance with proposed particle limit values, and further local

measures may be required to be compliant.

Other legislations to abate NH emissions include the Industrial Emissions Directive (IED) (2010/75/EU)

which requires pig and poultry farms (above stated size thresholds) to reduce emissions using Best

Available Techniques. For the protection of vegetation and ecosystems, new revised “Critical Levels” (CL)

3 3

of NH concentrations were adopted in 2007 (see Table 1), of 1 µg/m and 3 µg/m annual mean for the

protection of lichens/bryophytes and higher plants under field conditions, respectively, which replaced

3 3

the previous CL annual mean value of 8 µg/m . A monthly critical level of 23 µg /m was retained as a

provisional value in order to deal with the possibility of high peak emissions during periods of manure

application (e.g. in spring) ([15]). In Germany, the recommended exposure limit for the protection of

ecosystems is 10 µg/m (TA Luft, Annex 1, [16]).
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SIST EN 17346:2020
EN 17346:2020 (E)

Table 1 — Summary of upper limits of NH concentrations for protection of ecosystems under

field conditions
Concentration Specification Types of locality
(µg/m )
1 UNECE Critical Level (annual mean) for Sensitive ecosystems in
lower plants (lichens, bryophytes) which the lichens and
bryophytes are important
components, e.g. designated
sites for nature
conservation and protection
of sensitive species, e.g.
Natura 2000 sites
3 UNECE Critical Level (annual mean) for Sensitive ecosystems in
higher plants which the higher plants are
important components, e.g.
designated sites for nature
conservation and protection
of sensitive species, e.g.
Natura 2000 sites
10 German First General Administrative Near installations
Regulation Pertaining the Federal
Immission Control Act Maximum near
installations where ecological
monitoring undertaken.
23 UNECE critical level (monthly mean) – for In close proximity to
peak emission periods such as in months emission sources
where slurry spreading takes place.

Improving knowledge on levels of NH in the ambient air and near sources is therefore important for the

assessment of:

— environmental effects on ecosystems (Contribution to eutrophication and acidification processes);

— contributions to the formation of PM and PM ;
10 2,5
— effectiveness of current and future abatement measures to reduce NH emissions.

The simplest to the latest state-of–the-art techniques for measurement of atmospheric NH are presented

in Table 2.
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SIST EN 17346:2020
EN 17346:2020 (E)

Table 2 — Measurement methods suitable for determination of atmospheric NH gas and

ammonium particle concentrations
Monitoring Methods Time resolution References
Integrative methods: passive
Passive diffusion samplers daily to monthly [17]
[18]
[19]
[20]
Integrative methods: active
Simple denuder systems with offline chemical analysis daily to monthly [17]
[19]
[21]
Annular denuder systems (ADS) with offline chemical hourly to daily [22]
analysis
Conditional sampling with denuders at different heights weekly to monthly [23]
(COTAG)
Continuous: wet chemistry methods
Annular Denuder Systems with online analysis hourly or better [24]
depending on set-
Membrane stripping with online analysis
Steam Jet Aerosol Collector Systems for gas and aerosol hourly or better [25]
depending on set-
[26]
Continuous: optical methods
Differential Optical Absorption Spectrometry (DOAS) hourly or better [27]
depending on set-
Tunable Diode Laser Absorption Spectrometry and hourly or better [28]
Quantum Cascade Laser (TDL and QCL AS, respectively) depending on set-
Photoacoustic spectrometry hourly or better [29]
depending on set-
Chemiluminescence with catalytic conversion hourly or better [30]
depending on set-
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SIST EN 17346:2020
EN 17346:2020 (E)

Integrative atmospheric sampling methods such as passive diffusion samplers and active samplers

provide measurement of concentrations of NH averaged over the chosen sampling time. The diffusive

samplers used include those that are available commercially and those that have been developed in-

house by organisations to meet specific research requirements. A full validation of diffusive sampling

methods for NH in accordance with the European Standard (EN 13528-2 [31]) would be costly and

would also require specialist facilities only available at well-equipped large metrological institutes.

Validation of the quantitative measurement of NH through comparison with “reference” methods is

problematic for NH as there is no currently accepted and defined reference method. Automatic

continuous analysers for NH , employing spectroscopic or other techniques (Table 2) are available

commercially, but there is a lack of robust published calibration data and procedures for reliable field

measurements under ambient concentrations and conditions [32].
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SIST EN 17346:2020
EN 17346:2020 (E)
1 Scope

This document specifies a method for the sampling and analysis of NH in ambient air using diffusive

sampling.

It can be used for NH measurements at ambient levels, but the concentration range and exposure time

are sampler dependent, and the end user is therefore advised to match the sampler type to the

measurement requirement and to follow the operating instructions provided by the manufacturer.

2 Normative references
There are no normative references in this document.
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/ui
3.1
combined standard measurement uncertainty
combined standard uncertainty

standard measurement uncertainty that is obtained using the individual standard measurement

uncertainties associated with the input quantities in a measurement model
[SOURCE: JCGM 200:2012, 2.31] [33]
3.2
extraction efficiency
ratio of the mass of analyte extracted from a sampling device to that applied
3.3
diffusive sampler

device which is capable of taking samples of gases or vapours from the atmosphere at a rate controlled

by a physical process such as gaseous diffusion through a static air layer or a porous material and/or

permeation through a membrane, but which does not involve the active movement of air through the

device
Note 1 to entry: Active normally refers to the pumped movement of air.
[SOURCE: EN 13528-2:2002, 3.6] [31]
3.4
diffusive sampling rate
diffusive uptake rate

rate at which the diffusive sampler collects a particular gas or vapour from the atmosphere

3 3

Note 1 to entry: The sampling rate is usually expressed in units of (m /h), (ml/min) or (cm /min).

3 3 –8

Note 2 to entry: cm /min may be converted to SI units of m /s by factor 1,67 × 10 .

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SIST EN 17346:2020
EN 17346:2020 (E)
3.5
expanded measurement uncertainty

product of a combined standard measurement uncertainty and a factor larger than the number one

Note 1 to entry: The factor depends upon the type of probability distribution of the output quantity in a

measurement model and on the selected coverage probability.

Note 2 to entry: The term “factor” in this definition refers to a coverage factor.

[SOURCE: JCGM 200:2012, 2.35]
3.6
field blank

unused sampler, taken from the same batch used for NH monitoring, handled in the same way as a

sampler that is used for NH monitoring, except it is not used for collecting a sample

Note 1 to entry: Adapted from EN 14902:2005, 3.1.6.

Note 2 to entry: The results from the analysis of field blanks are used to identify contamination of the sample

arising from handling in the field and during transport.
[SOURCE: EN 1540:2011, 3.3.8] [34]

Note 3 to entry: A transport blank is considered to be a special case of a field blank. A transport blank is taken to

the exposure site, left unopened and returned to the laboratory immediately after placement or collection of the

samplers. Transport blanks may be used when regular field blanks reveal an unacceptable level of ammonium to

investigate the possibility of contamination of samplers during transport. This blank is only used for quality control

purposes.
3.7
laboratory blank

sealed sampler drawn from the same batch as the samplers being used for NH monitoring which is stored

for the duration of the sampling period and is analysed at the same time as the exposed samplers

3.8
measurement uncertainty
uncertainty of measurement

non-negative parameter characterizing the dispersion of the quantity values being attributed to a

measurand, based on the information used

Note 1 to entry: For notes to the definition the reader is referred to the parent document JCGM 200:2012.

[SOURCE: JCGM 200:2012, 2.26]
3.9
standard measurement uncertainty
standard uncertainty
measurement uncertainty expressed as a standard deviation
[SOURCE: JCGM 200:2012, 2.30]
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SIST EN 17346:2020
EN 17346:2020 (E)
4 Description of samplers
4.1 Principle

The diffusive sampler is exposed in air for a measured time period. NH migrates through the sampler

along a diffusion path of defined dimensions and is collected by reaction onto an acid sorbent.

Determining the sampling rate is essential when deploying diffusive NH samplers in the field, either by:

— calculation based on Fick’s first law of diffusion (see EN 13528-3 [35] and Annex E),

— calibration by exposure to standard atmospheres, or

— co-located calibration studies against another well characterized NH measurement method in the

field.

NOTE Denuders can be used as a cost effective surrogate reference method until there are improvements in

the continuous optical methods.
Details of these approaches shall be documented.

Samplers can be provided with manufacturer measured sampling rates. Samplers in networks often have

on-going measurements of sampling rates. Users can calculate a locally derived sampling rate. Sampling

rates are also documented in literature [see [36], and Annex D].

The sampling rate in the field is a function of local meteorology. Samplers can be deployed with protective

shelters to minimize meteorological influences. When doing so, the user shall apply a suitable protocol to

ensure a consistent approach for all samplers. Ideally, the effect of the shelter on the sampler

performance should be characterized.
4.2 Implementation

Samplers shall be sealed and stored under cool conditions, for example at temperatures between 0 °C and

4 °C, in the dark, in order to minimize any undesired reactions before and after deployment. After

deployment, samplers shall be analysed as soon as possible, according to manufacturer’s specifications.

Disposable gloves shall be worn at all times, including during deployment in the field. This serves to

protect the samples from contamination by contact with the skin. It is also advised to avoid breathing

directly on the samples, as exhaled breath contains NH .

Since there are different sampler designs, each common sampler type is briefly described below.

4.3 Tube-type samplers

The tube-type samplers are hollow cylindrical tubes oriented vertically. A cap at the top end holds in

place either a cellulose filter paper, glass fibre filter or stainless steel grid, which is coated with a sorbent

that collects the gas of interest. This type of sampler is characterized by a high length to cross sectional

area ratio [15, 37]. To collect NH , sorbents used include citric, phosphoric, phosphorous, sulphuric and

tartaric acid [38]. The analysis is carried out using various methods including ion chromatography, flow

injection analysis with detection of conductivity and spectrophotometry.

There is one commonly used design of tube type samplers, the 3,5 cm short membrane diffusion tube.

For more information, see Annex A.
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SIST EN 17346:2020
EN 17346:2020 (E)
4.4 Badge-type samplers

The badge-type samplers have a lower length to area ratio of the sample body, with enhanced sensitivity

over the tube-type samplers [15, 37]. There are many badge-type samplers in use with different

geometry. Due to the short diffusion path length, they have a gas permeable barrier at the inlet to prevent

wind-induced turbulent diffusion (wind shortening effect on sampling rate). The sorbents used to collect

ammonia are the same as employed with tube-type samplers, and the following analytical assessment is

performed by using the same techniques.
For more information, see Annex B.
4.5 Radial samplers

The radial-type sampler has a cylindrical outer surface that acts as a permeation barrier through which

NH diffuses [39]. NH molecules move axially parallel towards an absorbent bed that is also cylindrical

3 3

and coaxial to the diffusive surface. This type of sampler uses phosphoric acid as a sorbent. Exposed

samplers are analysed using various methods, including spectrophotometry, and ion chromatography.

For more information, see Annex C.
5 Calculation of the concentration of NH
5.1 Mass concentration

The concentration of NH in ambient air under actual conditions of sampling is calculated using

Formula (1):
mm−
3 sb
c= .
M e⋅⋅υ t
(1)
where
c is the concentration of NH at ambient conditions in µg/m ;
is the molar mass of NH in g/mol;
M 3
is the molar mass of NH in g/mol;
M 4
m is the mass of ammonium found in the sample in µg;
m is the mass of ammonium found in the mean laboratory blank in µg;

NOTE 1 In normal operations the transport and field blanks are expected to record similar masses of

ammonium compared to the laboratory blank. In cases where the transport and/or field blank is higher than

the laboratory blank the transport or field blank can be used for the subtraction. This information needs to be

clearly documented.
υ 3
is the sampling rate at ambient conditions during sampling in m /h;
e is the efficiency of extraction of ammonium;

NOTE 2 It is not necessary to include the efficiency of extraction of ammonium if this efficiency is shown not

be significantly different from 100 % or if it is already included into the estimation of the sampling rate.

t is the sampling time in h.

NOTE 3 The sampling rate can be in µg/(nmol/mol)/min, in which case c is expressed in units of nmol/mol.

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SIST EN 17346:2020
EN 17346:2020 (E)
5.2 Conversion to standard conditions of temperature and pressure

The mass concentration of NH in air is calculated at the ambient temperature and pressure during

exposure using Formula (1). This mass concentration shall be referred to at standard conditions of

temperature and pressure, as required in Directive 2008/50/EC [40] and defined e.g. by EN 16339 [41],

using Formula (2):
T 101,3
cc=⋅⋅
STP
293 P
(2)
where
c is the concentration of NH at standard temperature and pressure in µg/m ;
STP 3
c is the concentration of NH at ambient conditions in µg/m ;
T is the average temperature during exposure in K;
P is the average pressure during exposure in kPa.

NOTE Temperature and pressure data can be obtained from nearby meteorological stations.

6 Quality control/quality assurance
6.1 Quality control

For each series of analyses, the following control checks shall be performed and recorded:

a) inspection of each sampler before and after exposure, reject those with visible damage or

contamination and record this information in the report;

b) analysis for each batch of samplers, field blanks, transport blanks and/or laboratory blanks to detect

contamination of samplers during transport, in the field and during subsequent storage and

handling;

c) analysis of calibration solutions to determine instrument drift and appropriate re-calibration at

regular intervals, e.g. at the start of each day . If a check of the calibration response is outside the

expected performance criteria of the instrument, then a further investigation is required to

demonstrate that it is functioning correctly.

NOTE For a linear calibration curve, a check can be carried out using at least 3 points (zero, 50 % of calibration

range and full scale).

At regular intervals, the following control checks shall be performed and registered:

d) analysis of reagent solutions to determine variations of reagent blank levels;

e) determination of extraction efficiency by spik
...

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