SIST-TP CEN/TR 16269:2011
(Main)Ambient air quality - Guide for the measurement of anions and cations in PM2,5
Ambient air quality - Guide for the measurement of anions and cations in PM2,5
This Technical Report specifies a method for the determination of the mass of water soluble NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+, Ca2+ in PM2,5 samples which can be used to comply with Directive 2008/50/EC.
This Technical Report describes a measurement method which comprises sampling of anions and cations as part of the PM2,5 particulate phase, sample extraction and analysis of anions and cations by ion chromatography. Alternately, cations, excluding ammonium can be analysed by inductively coupled plasma optical emission spectrometry (ICP-OES).
This Technical Report may be used at rural background monitoring sites that are in accordance with the requirements of Directive 2008/50/EC. However, since this Technical Report has not been validated in the field for these, or any other, monitoring site types, it may be considered equally applicable to all site types.
NOTE The detection limits described in this Technical Report method will be limited by the noise level of the detector and the variability of the mass in laboratory blank filters rather than by the concentrations of anions and cations in ambient air.
Außenluftqualität - Leitfaden zur Messung von Anionen und Cationen in PM2,5
In diesem Fachbericht wird ein Verfahren zur Bestimmung der Massen der wasserlöslichen Ionen NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+, Ca2+ in PM2,5 beschrieben, das die Anforderungen der Richtlinie 2008/50/EG erfüllt.
Das beschriebene Messverfahren umfasst die Probenahme von Anionen und Kationen als Teil der Partikelfraktion PM2,5, die Extraktion der Probe und die Analyse der Anionen und Kationen mittels Ionenchromatographie. Die optische Emissionsspektrometrie mit induktiv gekoppeltem Plasma (ICP OES) kann als alternatives Analyseverfahren für Kationen, mit Ausnahme von Ammonium, angewendet werden.
Dieser Fachbericht kann für Messungen gemäß den Anforderungen der Richtlinie 2008/50/EG an ländlichen Hintergrundstationen angewendet werden. Obwohl für das in diesem Fachbericht beschriebene Verfahren keine Validierungsversuche im Feld durchgeführt wurden, wird davon ausgegangen, dass das Verfahren an allen Typen von Messstandorten anwendbar ist.
ANMERKUNG Die in diesem Fachbericht beschriebenen Verfahrensnachweisgrenzen sind eher durch das Detektorrauschen und die Streuung der Massen in den Laborblindfiltern als durch die Konzentrationen der Anionen und Kationen in der Außenluft bedingt.
Qualité de l'air ambiant - Guide pour le mesurage des anions et des cations dans la fraction PM2,5
Le présent Rapport technique CEN spécifie une méthode de détermination de la masse de NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+ et Ca2+ solubles dans l’eau dans des échantillons de PM2,5, qui peut être utilisée pour satisfaire à la Directive 2008/50/CE.
Le présent Rapport technique CEN décrit une méthode de mesurage qui comprend l’échantillonnage d’anions et de cations dans la phase particulaire de la fraction PM2,5, l'extraction des échantillons et l’analyse des anions et des cations par chromatographie ionique. Les cations, à l’exception de l’ammonium, peuvent également être analysés par spectrométrie d’émission optique à plasma induit par haute fréquence
(ICP-OES).
Le présent Rapport technique CEN peut être utilisé sur des sites ruraux de surveillance de la pollution de fond qui sont conformes aux exigences de la Directive 2008/50/CE. Cependant, étant donné que le présent Rapport technique CEN n’a pas été validé sur le terrain pour ces types de sites de surveillance, ou pour d’autres types de sites, il peut être considéré comme étant applicable à tous les types de sites.
NOTE Les limites de détection décrites dans la méthode du présent Rapport technique CEN seront restreintes par le niveau de bruit du détecteur et par la variabilité de la masse dans les filtres vierges de laboratoire plutôt que par les concentrations en anions et en cations dans l’air ambiant.
Kakovost zunanjega zraka - Vodilo za merjenje anionov in kationov v frakciji PM2,5
To tehnično poročilo določa metodo za določevanje mase vodotopnih vzorcev NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+, Ca2+ in PM2,5, ki se lahko uporablja za skladnost z Direktivo 2008/50/ES.
To tehnično poročilo opisuje merilno metodo, ki vključuje vzorčenje anionov in kationov kot del faze delcev PM2,5, ekstrakcijo vzorca ter analizo anionov in kationov z ionsko kromatografijo. Alternativno se lahko kationi, razen amonija, analizirajo z optično spektrometrijo z induktivno sklopljeno plazmo (ICP-OES).
To tehnično poročilo se lahko uporablja v podeželskih zalednih merilnih mestih, ki so v skladu z zahtevami Direktive 2008/50/ES. Ker to tehnično poročilo ni bilo validirano na terenu za merilna mesta te ali katere koli druge vrste, se lahko enako uporablja na vseh vrstah mest.
OPOMBA: Meje zaznavanja, opisane v metodi tega tehničnega poročila, so omejene z ravnmi hrupa detektorja in spremenljivostjo mase v laboratorijskih praznih filtrih in ne s koncentracijami anionov in kationov v zunanjem zraku.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TP CEN/TR 16269:2011
01-december-2011
Kakovost zunanjega zraka - Vodilo za merjenje anionov in kationov v frakciji PM2,5
Ambient air quality - Guide for the measurement of anions and cations in PM2,5
Außenluftqualität - Leitfaden zur Messung von Anionen und Cationen in PM2,5
Qualité de l'air ambiant - Guide pour le mesurage des anions et des cations dans la
fraction PM2,5
Ta slovenski standard je istoveten z: CEN/TR 16269:2011
ICS:
13.040.20 Kakovost okoljskega zraka Ambient atmospheres
SIST-TP CEN/TR 16269:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST-TP CEN/TR 16269:2011
---------------------- Page: 2 ----------------------
SIST-TP CEN/TR 16269:2011
TECHNICAL REPORT
CEN/TR 16269
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
September 2011
ICS 13.040.20
English Version
Ambient air - Guide for the measurement of anions and cations
in PM2,5
Air ambiant - Guide pour le mesurage des anions et des Außenluft - Leitfaden zur Messung von Anionen und
cations dans la fraction PM2,5 Kationen in PM2,5
This Technical Report was approved by CEN on 8 August 2011. It has been drawn up by the Technical Committee CEN/TC 264.
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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TR 16269:2011: E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
Contents Page
Foreword .3
Introduction .4
1 Scope .5
2 Terms and definitions .5
3 Symbols and abbreviations .6
4 Principle .8
5 Apparatus .8
6 Sampling, transport and storage . 11
7 Analysis . 11
8 Calculation of results . 12
9 Quality control . 15
10 Measurement uncertainty . 17
11 Artefacts and interferences . 17
12 Reporting of results . 18
Annex A (informative) Example of a closed vessel microwave digestion procedure to determine
elements in the water-insoluble fraction of PM . 19
2,5
Annex B (informative) Preparation of stock standard solution . 21
Annex C (informative) Uncertainty budget. 22
Annex D (informative) Data quality objectives . 24
Annex E (informative) Reagents . 26
Bibliography . 31
2
---------------------- Page: 4 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
Foreword
This document (CEN/TR 16269:2011) has been prepared by Technical Committee CEN/TC 264 “Air quality”,
the secretariat of which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
3
---------------------- Page: 5 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
Introduction
This CEN Technical Report describes how to measure a specified range of anions and cations in PM .
2,5
The new EU Air Quality Directive 2008/50/EC on ambient air quality and cleaner air for Europe requests the
- 2- - + + + 2+ 2+
measurements of concentrations of NO , SO , Cl , NH , Na , K , Mg , Ca in PM at rural background
3 4 4 2,5
locations. In Annex IV of the Directive, guidance for these measurements is given (see Annex D).
Until now measurements of anions and cations in PM have been performed by the EMEP programme, mainly
by using a filterpack with limited size selectivity. The Cooperative programme for monitoring and evaluation of
long-range transmission of air pollutants in Europe (EMEP) was launched in 1977 as a response to the
growing concern over the effects on the environment caused by acid deposition. EMEP was organized under
the auspices of the United Nations Economic Commission for Europe (UNECE). Today EMEP is an integral
component of the cooperation under the Convention on Long-range Transboundary Air Pollution.
Directive 2008/50/EC requires that measurements at rural sites, where appropriate, shall be coordinated with
the monitoring strategy and measurement programme of EMEP. Although, there are different sampling
procedures involved, a common approach is used for the analytical procedure.
In order to keep the agreement between existing EMEP data and data to be produced using this CEN
technical report as close as possible, the EMEP protocol has been taken as starting point for this CEN
technical report. This CEN technical report differs from the EMEP protocol in the sense that measurement of
anions and cations are done in PM , and that a number of critical parameters (e.g. choice of filter materials)
2,5
are fixed.
Additional attention is given to harmonizing these critical parameters with elemental carbon/organic carbon
(EC/OC) measurements and with PM measurements as well, as the sampling usually is done
2,5
simultaneously.
Finally, it should be noted that this CEN Technical Report has been produced in order to give assistance to
those making measurements in accordance with Directive 2008/50/EC as rapidly as possible. However, there
are still some open issues, including the influence of various sampling artefacts on the data quality, which can
only be answered via validation work. This CEN Technical Report is not intended to supersede existing
(inter)national standards or harmonized methods.
4
---------------------- Page: 6 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
1 Scope
- 2-
This CEN Technical Report specifies a method for the determination of the mass of water soluble NO , SO ,
3 4
- + + + 2+ 2+
Cl , NH , Na , K , Mg , Ca in PM samples which can be used to comply with Directive 2008/50/EC.
4 2,5
This CEN Technical Report describes a measurement method which comprises sampling of anions and
cations as part of the PM particulate phase, sample extraction and analysis of anions and cations by ion
2,5
chromatography. Alternately, cations, excluding ammonium can be analysed by inductively coupled plasma
optical emission spectrometry (ICP-OES).
This CEN Technical Report may be used at rural background monitoring sites that are in accordance with the
requirements of Directive 2008/50/EC. However, since this CEN Technical Report has not been validated in
the field for these, or any other, monitoring site types, it may be considered equally applicable to all site types.
NOTE The detection limits described in this CEN technical report method will be limited by the noise level of the
detector and the variability of the mass in laboratory blank filters rather than by the concentrations of anions and cations in
ambient air.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
ambient air
outdoor air in the troposphere excluding workplace air
[EN 14907]
2.2
high volume sampling method
HVS
3
method for sampling particulate matter with a flow rate of 30 m /h
[EN 14907]
2.3
low volume sampling method
LVS
3
method for sampling particulate matter with a flow rate of 2,3 m /h
[EN 14907]
2.4
PM
2,5
fraction of suspended particulate matter which passes through a size-selective inlet with a 50 % cut-off
efficiency at 2,5 µm aerodynamic diameter
[EN 14907]
2.5
PM
10
fraction of suspended particulate matter which passes through a size-selective inlet with a 50 % cut-off
efficiency at 10 µm aerodynamic diameter
5
---------------------- Page: 7 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
2.6
suspended particulate matter
SPM
notion of all particles surrounded by air in a given, undisturbed volume of air
[EN 14907]
2.7
measurement uncertainty
non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand,
based on the information used
[JGCM 200:2008 (VIM)]
3 Symbols and abbreviations
For the purposes of this document, the following symbols and abbreviated terms apply.
3.1 Symbols
3
γ mass concentration of anions or cations in ambient air, in µg/m
amb
th
δ deviation of the i calibration point from the best-fit calibration relationship
i
I peak area on the ion chromatogram for the relevant ion generated from measurement i
i
I peak area on the ion chromatogram for the relevant ion measured on the sampled filter
sam
I average of n measurements of I
i
I average peak area on the ion chromatogram for the relevant ion measured on a given number of blank
blk
filters
k coverage factor to provide a 95 % level of confidence, usually assumed to be equal to 2
th
m mass of anions or cations measured on the i blank filter in a set of n , in µg
blk,i
m average of n measurements of m
blk blk
m mass of extraction solution, in g
t
ext
m filter blank corrected mass of anions or cations measured in the PM on the sampled filter, in µg
ion
m method detection limit, expressed in µg
MDL
2 2
r ratio of sub-sampled filter area to the total filter area, in m /m
R peak resolution
6
---------------------- Page: 8 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
σ relative standard deviation of a set of n measurements
R
s relative standard deviation of the measured analytical response in the centre of the application range
based on 10 repeat measurements
s relative standard deviation of the measurements of multiple extractions of sub-samples from the same
D
filter
th
s standard deviation of the measured analytical response for the i calibration point
i
t retention time, in seconds, of the first peak
1
t retention time, in seconds, of the second peak
2
ux() estimated standard uncertainty in x
U relative expanded uncertainty of the measurement result
r
3
V volume of ambient air sampled, in m
amb
&
V gradient of calibration curve (sensitivity) produced by the ion chromatograph, in g/µg
cal
&
V measured sensitivity of the instrument at time t = 0
cal, 0t=
&
V measured sensitivity of the instrument at time t
cal, tt=
&
∆V drift in the sensitivity of the ion chromatograph over a time, t
cal
w peak width on the time axis, in seconds, of the first peak
1
w peak width on the time axis, in seconds, of the second peak
2
w peak width of peak i
i
x filter blank corrected mass fraction of anions or cations in the PM extract, in µg/g
ext
3.2 Abbreviations
CD conductivity detector
EA European cooperation for accreditation
FEP hexafluoroethene propene
HDPE high density polyethene
HPLC high performance liquid chromatography
HVS high volume sampler
7
---------------------- Page: 9 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
ICP-MS inductively coupled plasma atomic mass spectrometry
ICP-OES inductively coupled plasma optical emission spectrometry
LVS low volume sampler
MLA multi-lateral agreement
NIST national institute for standards and technology
PE polyethene
PFA perfluoroalkoxy
PM particulate matter
PP polypropylene
PTFE polytetrafluoroethene
SPM suspended particulate matter
UV ultraviolet
4 Principle
This method allows the determination of anions (chloride, nitrate and sulfate) and cations (sodium,
ammonium, potassium, magnesium and calcium) in PM collected on filters used for sampling ambient air.
2,5
The method is divided into two main parts: the sampling in the field and the analytical procedure in the
laboratory.
During the sampling, particles containing anions and cations are collected by drawing a measured volume of
air through a filter mounted in a sampler designed to collect the PM fraction of suspended particulate matter.
2,5
The sampled filter is transported to the laboratory, where the anions and cations are taken into solution by
ultrasonic extraction with deionised water. The resultant extract is analysed separately for anions and cations
by ion chromatography (for all ions), or ICP-OES (for cations, except ammonium).
5 Apparatus
5.1 Sampling equipment
5.1.1 PM samplers, in conformity with EN 14907.
2,5
High volume samplers (HVS) or low volume samplers (LVS) may be used and the samplers may be single-
filter devices or sequential samplers.
NOTE To minimise contamination of the sample, all components of the filter holder in contact with the filter should be
made of a suitable material with as low a metal and salt content as possible, such as polytetrafluoroethene (PTFE), glass,
quartz etc.
8
---------------------- Page: 10 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
5.1.2 Greasing agent, if required, suitable for greasing the sampler impaction plate.
5.1.3 Filters, of a diameter suitable for use with the samplers (5.1.1), with a separation efficiency of at least
99,5 % at an aerodynamic diameter of 0,3 µm.
Any filter type in accordance with EN 14907 may be used (i.e. glass fibre, quartz fibre, PTFE or PTFE coated
glass fibre filters), provided that the requirements for the method detection limit (9.7) are met. Also, each new
batch of filters should be tested to confirm that the filter blank variability is sufficiently low that the method
detection requirements are met.
NOTE 1 It is recommended that filters used should be sourced from a manufacturer who has determined the
separation efficiency of the filter material according to standard methods such as EN 13274-7 or EN 1822-1.
NOTE 2 The anion and cation content of the filter should be as low as possible because it is usually the case that
higher filter blank values lead to higher variability of the blank values.
NOTE 3 In choosing a filter, the user should consider the initial pressure drop across the filter and the increase in this
that occurs due to the collection of the dust and ensure that there is no possibility of an excessive pressure drop
developing during sampling. This depends on the type of filter (i.e. membranes), unusual high concentrations of PM , the
2,5
use of longer sampling time than 24h and the capability of the sampling device to handle the resulting pressure drop.
Quartz fibre filters are proven to be efficient in most cases although they may have weak mechanical properties.
NOTE 4 Glass and/or quartz fibre filters may be washed with deionised water before sampling in order to lower blank
values
5.1.4 Flowmeter, with a measurement uncertainty that is sufficient to enable the volumetric flow rate of the
samplers (5.1.1) to be measured to within ±5 %.
The calibration of the flowmeter should be traceable to (inter)national standards.
The expanded uncertainty (at 95 % confidence) of the transfer standard flow meter measurements should be
better than 2 % at laboratory conditions. If the flow rate determined using the transfer standard deviates more
than 2 % from the value required for correct operation of the inlet, the flow controller should be adjusted
according to the manufacturer's instructions.
5.2 Laboratory apparatus
5.2.1 General requirements
All surfaces in contact with the sample, measuring and calibration solutions should be made of inert material
with respect to the analytes measured. In the working range of this method high density polyethylene (HDPE)
is normally a suitable material. However, always check the material with respect to the specific purpose, e. g.
for the storage of standard solutions as well as for the determination of elements at an ultra-trace level,
fluorocarbon polymer materials such as perfluoroalkoxy (PFA) or hexafluoroethene propene (FEP) may be
advantageous. If cations are to be analysed, do not use glass surfaces.
Wash all labware thoroughly with water (E.2.1) before use. Labware dedicated to the use for analysis of
cations should additionally be washed thoroughly with diluted nitric acid (e.g., mass content w(HNO ) = 1 %)
3
in prior to use. Do not use nitric acid for cleaning labware used for analysing anions.
NOTE Contaminated labware can be cleaned with hot tap water and alkaline detergent before being taken through
the normal cleaning procedure.
5.2.2 General labware
In addition to ordinary laboratory apparatus (e. g. a range of volumetric flasks, Erlenmeyer flasks and pipettes)
the equipment as given under 5.2.3 to 5.2.6 is needed. If ICP-OES is chosen for analysis of cations (except
ammonium) the equipment given under 5.2.7 is additionally required.
9
---------------------- Page: 11 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
5.2.3 Storage bottles, for the stock, standard, calibration and sample solutions
5.2.4 Dispensers, variable volume
NOTE The use of piston pipettes is allowed. It enables the preparation of lower volumes of calibration solutions. The
application of dilutors is also allowed. Test each batch of pipette tips and disposable plastics vessels for impurities.
5.2.5 Filtration equipment
Membrane filtration equipment and membrane filters of a medium pore size 0,45 µm reserved for trace
element determination. PE, PP and PTFE filtering apparatus are recommended to avoid possible
contamination with, or adsorption by, metal elements. Test each batch of membrane filters for impurities.
Alternatively, single use syringe filters (e.g. cellulose acetate or nylon; pore size 0,45 µm) together with single
use medical syringes can be used.
5.2.6 Ion chromatography system
In general, it consists of the following components:
5.2.6.1 Eluent reservoir, and a degassing unit
5.2.6.2 Metal-free high performance liquid chromatography (HPLC) pump
5.2.6.3 Sample injection system, incorporating a sample loop of appropriate volume (e.g. 0,02 ml) or
autosampler device
5.2.6.4 Separator column, with the specified separating performance
5.2.6.5 Conductivity detector (CD)
5.2.6.6 UV detector, e.g. a spectrophotometer, operating over the wavelength range: 190 nm to 400 nm,
optionally used in combination with a CD for the determination of nitrate or nitrite
5.2.6.7 Recording device, e.g. a computer with software for data acquisition and evaluation
5.2.6.8 Precolumns, if necessary
5.2.6.9 Suppressor device, if necessary
5.2.7 Inductively coupled plasma optical emission spectrometer system
In general, it consists of the following components:
5.2.7.1 Computer-controlled optical emission spectrometer with background correction
5.2.7.2 Radiofrequency generator
5.2.7.3 Mass-flow controller
A mass-flow controller on the nebulizer gas supply is recommended.
NOTE The plasma is very sensitive to variations in the gas flow rate of the nebulizer gas.
10
---------------------- Page: 12 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
5.2.7.4 Nebulizer, with variable speed peristaltic pump
Common nebulizers are the concentric nebulizer (e.g., Meinhard), the cross-flow nebulizer, the V-groove
nebulizer and a cyclonic chamber with or without baffles. Other types of nebulizers may also be used if it can
be shown that they are fit for purpose.
5.2.7.5 Ultrasonic nebulizer
If very low concentration measurements are to be achieved, ultrasonic nebulizers are recommended. In this
special type of nebulizer the sample solution is pumped through a tube that ends near the transducer plate
that vibrates at an ultrasonic frequency. The amount of aerosol produced (the efficiency) is typically 10 % to
20 % of the quantity of the pumped solution. As this is very high, the aerosol needs to be dried (desolvated)
before being introduced into the plasma, which otherwise would be extinguished. The aerosol is transported to
the plasma by the nebulizer gas.
Disadvantages of the ultrasonic nebulizer include its greater susceptibility to matrix effects, diminished
tolerance to high dissolved solid contents (approximately > 0,5 % m/v) and a longer rinsing time. Vapour
generation apparatus for hydride or cold vapour can also be used for sample introduction.
5.2.7.6 Argon gas supply
Argon gas with a sufficient purity grade, for instance > 99,95 %.
6 Sampling, transport and storage
Sampling, as well as transport and storage of unloaded filters, should be performed according to EN 14907.
NOTE EN 14907 is under revision and will be included in the forthcoming revision of EN 12341.
7 Analysis
7.1 Filter sub-sampling
For extraction of water-soluble constituents from the PM filters, the whole filter can be used or a
2,5
sub-sample, representative of the filter as a whole, may be taken. This can be done by using an appropriate
cutting device to obtain an accurately defined part of the exposed area of the sampled filter.
7.2 Sample extraction
The filters are put into a sample tube and deionised water is added.
The extraction volume should be as small as possible, but enough to completely cover the sample, typically at
least 10 ml, for 47 mm filters.
The sample tubes should be exposed in an ultrasonic bath for at least 30 minutes to obtain complete
extraction.
7.3 Sample preparation
If any filter material is expected to be present in the extract, the extracts should be filtered or centrifuged prior
to analysis.
11
---------------------- Page: 13 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
7.4 Analysis of extracts
- 2- - + + + 2+ 2+
The analysis of NO , SO , Cl, NH , Na , K , Mg , Ca should follow EN ISO 10304-1 and
3 4 4
EN ISO 14911 for ion chromatography or the procedure described in chapter 4.1 of the EMEP manual. A
small volume of the sample, typically less than 0,5 ml, is introduced into the injection system of an ion
chromatograph. The sample is mixed with an eluent and pumped through a guard column, a separation
column, a suppressor device and a detector.
The ion chromatograph should be calibrated with standard solutions containing known concentrations of the
ions. At least five calibration solutions and one zero standard (blank solution of only deionized water) should
be used to generate a suitable calibration curve. The concentration range depends on the sample; the
calibration curve should cover concentrations lower and higher than the measured concentration.
NOTE 1 The calibration standards may contain 0, 0,5, 1,0, 2,5, 5,0 and 10,0 mg/l of the different ions. An example of
the preparation of standard solutions is found in Annex B.
Special attention should be paid to control contamination from ammonia in the laboratory air. All reagents
should be of recognized analytical grade. The water used for dilution should be deionized and filtered.
NOTE 2 Any other analytical method shown to be equivalent using the EC equivalence procedure may be used [11]
NOTE 3 Further metal and metalloid constituents, including mineral dust constituents (e.g. Al, Zn, Fe), can be analysed
with ICP–OES after digestion. A suitable digestion procedure is given in Annex A.
8 Calculation of results
8.1 General
It is intended that the following equations for the calculation of results be applied to samples of PM ,
2,5
collected according to EN 14907.
The data quality objectives of Directive 2008/50/EC shall be met at all times.
8.2 Calculation of anion and cation mass concentration in ambient air
The mass concentration of anions and cations in ambient PM using this standard method may be described
2,5
by the following equation:
m
ion
γ = (1)
amb
V
amb
where
3
γ is the mass concentration of anions or cations in ambient air, in µg/m ;
amb
3
V is the volume of ambient air sampled, in m ;
amb
m is the filter blank corrected mass of anions or cations measured in the PM on the sampled filter, in µg.
ion
NOTE 1 It is assumed that sampling is carried out according to EN 14907 and that sampled PM is analysed as
received. Therefore no term is included to account for any loss of volatile material during sampling, or for any deviation
from the sampling of PM by the standard method.
2,5
12
---------------------- Page: 14 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
Furthermore, the mass of anions or cations measured on the sampled filter may be calculated by:
mx
ext ext
m = (2)
ion
r
where
x is the filter blank corrected mass fraction of anions or cations in the PM extract, in µg/g;
ext
m is the mass of extraction solution, in g;
ext
2 2
r is the ratio of sub-sampled filter area to the total filter area, in m /m .
NOTE 2 If the sampled filter is not sub-sampled prior to analysis then r will be equal to unity with no uncertainty and
may be neglected.
Furthermore, the mass fraction of anions and cations in the PM extract may be calculated by:
I − I
sam blk
x = (3)
ext
&
V
cal
where
I is the peak area on the ion chromatogram for the relevant ion measured on the sampled filter;
sam
I is the average peak area on the ion chromatogram for the relevant ion measured on a given number of
blk
blank filters;
&
V is the gradient of calibration curve (sensitivity) produced by the ion chromatograph, in g/µg.
cal
Equation (3) assumes that the same mass of solution is used to extract the sampled filter and the blank filter.
If this is not the case an appropriate correction based on the differences in solution masses should be applied
to Equation (3).
8.2.1 Blank correction for ionic content in filter material
It is important to note that the ionic content of the blank filters used to sample the ambient PM may be
significant. It is therefore important that a blank correction is made for this value as shown in Equation (3).
Given that it is not possible to measure the blank content of the individual filters used to perform sampling, it is
important that a number of filters from the same batch are measured in order to obtain a mean blank value
and the variability in this value.
Determinations of the mass of ions on a blank filter may be made using the analogous relationships to
Equations (2) and (3), but in this case considering the blank filter as the sample and the extraction medium as
the blank.
8.3 Method detection limit
The method detection limit, m , expressed in µg, is defined as:
MDL
13
---------------------- Page: 15 ----------------------
SIST-TP CEN/TR 16269:2011
CEN/TR 16269:2011 (E)
n
2
mm−
()
∑
blk blk,i
i=1
m = 3 (4)
MDL
n−1
where
th
m is the mass of anions or cations measured on the i blank filter in a set of n , in µg;
blk,i
m is the average of n measurements of m ;
blk blk
NOTE This may be converted into a method detection limit in mass concentration terms by dividing m by the
MDL
volume of ambient air sampled during a normal sampling period.
8.4 Repeatability
The repeatability is the closeness of agreement of successive measurements of the same measurand carried
out under the same conditions of measurement. Quantitatively this can be expressed as the relative standard
deviation of a set of repeat measurements, thus:
in=
2
I − I
()
∑
i
1
i=1
σ = (5)
R
In−1
where
σ is the relative standard deviation of a set of n measurements;
R
I is the peak area on
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.