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SIST EN ISO 11885:2009
01-december-2009
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SIST EN ISO 11885:1998
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Water quality - Determination of selected elements by inductively coupled plasma optical
emission spectrometry (ICP-OES) (ISO 11885:2007)
Wasserbeschaffenheit - Bestimmung von ausgewählten Elementen durch induktiv
gekoppelte Plasma-Atom-Emissionsspektrometrie (ICP-OES) (ISO 11885:2007)
Qualité de l'eau - Dosage d'éléments choisis par spectroscopie d'émission optique avec
plasma induit par haute fréquence (ICP-OES) (ISO 11885:2007)
Ta slovenski standard je istoveten z: EN ISO 11885:2009
ICS:
13.060.50 3UHLVNDYDYRGHQDNHPLþQH Examination of water for
VQRYL chemical substances
SIST EN ISO 11885:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 11885:2009
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SIST EN ISO 11885:2009
EUROPEAN STANDARD
EN ISO 11885
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2009
ICS 13.060.50 Supersedes EN ISO 11885:1997
English Version
Water quality - Determination of selected elements by
inductively coupled plasma optical emission spectrometry (ICP-
OES) (ISO 11885:2007)
Qualité de l'eau - Dosage d'éléments choisis par Wasserbeschaffenheit - Bestimmung von ausgewählten
spectroscopie d'émission optique avec plasma induit par Elementen durch induktiv gekoppelte Plasma-Atom-
haute fréquence (ICP-OES) (ISO 11885:2007) Emissionsspektrometrie (ICP-OES) (ISO 11885:2007)
This European Standard was approved by CEN on 14 May 2009.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11885:2009: E
worldwide for CEN national Members.
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SIST EN ISO 11885:2009
EN ISO 11885:2009 (E)
Contents Page
Foreword .3
2
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SIST EN ISO 11885:2009
EN ISO 11885:2009 (E)
Foreword
The text of ISO 11885:2007 has been prepared by Technical Committee ISO/TC 147 “Water quality” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 11885:2009 by
Technical Committee CEN/TC 230 “Water analysis” 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 2009, and conflicting national standards shall be withdrawn
at the latest by November 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11885:1997.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, 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 the United Kingdom.
Endorsement notice
The text of ISO 11885:2007 has been approved by CEN as a EN ISO 11885:2009 without any modification.
3
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SIST EN ISO 11885:2009
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SIST EN ISO 11885:2009
INTERNATIONAL ISO
STANDARD 11885
Second edition
2007-08-01
Water quality — Determination of
selected elements by inductively coupled
plasma optical emission spectrometry
(ICP-OES)
Qualité de l'eau — Dosage d'éléments choisis par spectroscopie
d'émission optique avec plasma induit par haute fréquence (ICP-OES)
Reference number
ISO 11885:2007(E)
©
ISO 2007
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
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© ISO 2007
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Published in Switzerland
ii © ISO 2007 – All rights reserved
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Principle.5
5 Recommended wavelengths, limits of quantification and important spectral interferences.5
6 Interferences .9
7 Reagents.11
8 Apparatus .14
9 Sampling and preservation.15
10 Procedure .18
11 Expression of results .20
12 Test report .20
Annex A (informative) Special digestion methods .21
Annex B (informative) Precision data.22
Annex C (informative) Description of the matrices of the samples used for the interlaboratory trial .26
Bibliography .28
© ISO 2007 – All rights reserved iii
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 11885 was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 2, Physical,
chemical and biochemical methods.
This second edition cancels and replaces the first edition (ISO 11885:1996), which has been technically
revised.
iv © ISO 2007 – All rights reserved
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Introduction
When applying this International Standard, it is necessary in each case, depending on the range to be tested,
to determine if and to what extent additional conditions should be established.
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SIST EN ISO 11885:2009
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SIST EN ISO 11885:2009
INTERNATIONAL STANDARD ISO 11885:2007(E)
Water quality — Determination of selected elements by
inductively coupled plasma optical emission spectrometry
(ICP-OES)
WARNING — Persons using this International Standard should be familiar with normal laboratory
practice. This International Standard does not purport to address all of the safety problems, if any,
associated with its use. It is the responsibility of the user to establish appropriate safety and health
practices and to ensure compliance with any national regulatory conditions.
IMPORTANT — It is absolutely essential that tests conducted according to this International Standard
be carried out by suitably trained staff.
1 Scope
This International Standard specifies a method for the determination of dissolved elements, elements bound to
particles (“particulate”) and total content of elements in different types of water (e.g. ground, surface, raw,
potable and waste water) for the following elements: aluminium, antimony, arsenic, barium, beryllium,
bismuth, boron, cadmium, calcium, chromium, cobalt, copper, gallium, indium, iron, lead, lithium, magnesium,
manganese, molybdenum, nickel, phosphorus, potassium, selenium, silicon, silver, sodium, strontium, sulfur,
tin, titanium, tungsten, vanadium, zinc and zirconium.
Taking into account the specific and additionally occurring interferences, these elements can also be
determined in digests of water, sludges and sediments (for example, digests of water as specified in
ISO 15587-1 or ISO 15587-2). The method is suitable for mass concentrations of particulate matter in waste
water below 2 g/l. The scope of this method may be extended to other matrices or to higher amounts of
particulate matter if it can be shown that additionally occurring interferences are considered and corrected for
carefully. It is up to the user to demonstrate the fitness for purpose.
Recommended wavelengths, limits of quantification and important spectral interferences for the selected
elements are given in Table 1.
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.
ISO Guide 30, Terms and definitions used in connection with reference materials
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 5667-1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and
sampling techniques
ISO 5667-3, Water quality — Sampling — Part 3: Guidance on the preservation and handling of water
samples
ISO 7027, Water quality — Determination of turbidity
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
ISO 15587-1, Water quality — Digestion for the determination of selected elements in water — Part 1: Aqua
regia digestion
ISO 15587-2, Water quality — Digestion for the determination of selected elements in water — Part 2: Nitric
acid digestion
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
accuracy
closeness of agreement between test result and the accepted reference value
NOTE The term accuracy, when applied to a set of observed values, describes a combination of random error
components and common systematic error components. Accuracy includes precision and trueness.
3.2
analyte
element(s) to be determined
3.3
background equivalent concentration
BEC
elemental concentration required to produce an analyte signal with the same intensity as a background signal
3.4
calibration blank solution
prepared in the same way as the calibration solution but leaving out the analyte
3.5
calibration solution
solution used to calibrate the instrument, prepared from (a) stock solution(s) or from a certified standard
3.6
calibration check solution
solution of known composition within the range of the calibration solutions, but prepared independently
3.7
determination
entire process from preparing the test sample solution up to and including measurement and calculation of the
final result
3.8
instrument performance check solution
solution used to determine and control the instrument drift for relevant analytes
3.9
linearity
straight line relationship between the (mean) result of measurement (signal) and the quantity (concentration)
of the component to be determined
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
3.10
limit of detection
X
LD
smallest amount or concentration of an analyte in the test sample that can be reliably distinguished from zero
NOTE The limit of detection shall be calculated as:
X = 3 s
LD 0
where
X is the limit of detection;
LD
s is the standard deviation of the outlier-free results of at least 3 measurements of a reagent blank solution (3.14)
0
[ISO 13530]
3.11
limit of quantification
X
LQ
the smallest amount or concentration of an analyte in the test sample which can be determined with a fixed
precision
EXAMPLE Relative standard deviation s = 33,3 %
rel
X==39Xs
LQ LD 0
[ISO 13530]
3.12
mean result
mean value of n results, calculated as intensity (ratio) or as mass concentration (ρ)
NOTE The mass concentration is expressed in units of milligrams per litre, mg/l.
3.13
precision
closeness of agreement between independent test results obtained under prescribed conditions
NOTE Precision depends only on the distribution of random errors and does not relate to true value or the specified
value.
3.14
reagent blank solution
prepared by adding to the solvent the same amounts of reagents as those added to the test sample solution
(same final volume)
3.15
reproducibility
precision under reproducibility conditions
[ISO 3534-2:2006, definition 3.3.10]
3.16
reproducibility conditions
observation conditions where independent test/measurement results are obtained with the same method on
identical test/measurement items in different test or measurement facilities with different operators using
different equipment
[ISO 3534-2:2006, definition 3.3.11]
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
3.17
reproducibility standard deviation
standard deviation of test results or measurement results obtained under reproducibility conditions
[ISO 3534-2:2006, definition 3.3.12]
3.18
reproducibility limit
R
reproducibility critical difference for a specified probability of 95 %
[ISO 3534-2:2006, definition 3.3.14]
3.19
repeatability
precision under repeatability conditions
[ISO 3534-2:2006, definition 3.3.5]
3.20
repeatability conditions
observation conditions where independent test/measurement results are obtained with the same method on
identical test/measurement items in the same test or measuring facility by the same operator using the same
equipment within short intervals of time
[ISO 3534-2:2006, definition 3.3.6]
3.21
repeatability standard deviation
standard deviation of test results or measurement results obtained under repeatability conditions
[ISO 3534-2:2006, definition 3.3.7]
3.22
repeatability limit
r
repeatability critical difference for a specified probability of 95 %
[ISO 3534-2:2006, definition 3.3.9]
3.23
stock solution
solution with accurately known analyte concentration(s), prepared from chemicals with an appropriate purity
NOTE Stock solutions are reference materials within the meaning of ISO Guide 30.
3.24
test sample
prepared from the laboratory sample (for example by grinding, homogenizing)
3.25
test sample solution
solution prepared with the fraction (test portion) of the test sample according to the appropriate specifications,
such that it can be used for the envisaged measurement
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
3.26
total element concentration
concentration of elements determined on an unfiltered sample following digestion or the sum of concentrations
of elements as determined in the dissolved state (9.5.1) and bound in the particulate fraction (9.5.2) of a
sample
3.27
trueness
bias
closeness of agreement between the average value obtained from a large series of test results and an
accepted reference value
NOTE The measure of trueness is usually expressed in terms of bias (bias = sum of systematic error components).
4 Principle
The basis of the method is the measurement of emission of light by an optical spectroscopic technique.
Samples are nebulized and the aerosol that is produced is transported to the plasma torch where excitation
occurs. Characteristic emission spectra are produced by a radio-frequency inductively coupled plasma (ICP).
The spectra are dispersed by a grating spectrometer and the intensities of the lines are monitored by a
detector. The signals from the detector(s) are processed and controlled by a computer system. A suitable
background correction technique is used to compensate for variable background contributions to the
determination of trace elements.
5 Recommended wavelengths, limits of quantification and important spectral
interferences
Elements for which this International Standard applies along with the recommended wavelengths and typical
estimated limits of quantification (LOQ) are listed in Table 1 as far as data are available from the
interlaboratory trial (see Annex B). Actual working detection limits are dependent on the type of
instrumentation, detection device and sample introduction system used and on the sample matrix. Therefore,
these concentrations can vary between different instruments.
Additionally, Table 1 lists the most important spectral interferences at the recommended wavelengths for
analysis.
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
a b
Table 1 — Recommended wavelengths , achievable limits of quantification (X )
LQ
for different types of instruments and important spectral Interferences
Element Wavelength Approx. X Interfering elements
LQ
Radial viewing Axial viewing
nm µg/l µg/l
Ag 328,068 (20) (4) Fe, Mn, Zr
338,289 (20) (10) Cr, Fe, Zr, Mn
Al 167,079 1 2 Fe, Pb
308,215 100 17 Fe, Mn, OH, V
396,152 10 6 Cu, Fe, Mo, Zr
As 188,979 18 14 Al, Cr, Fe, Ti
193,696 5 14 Al, Co, Fe, W, V
197,197 (100) 31 Al, Co, Fe, Pb, Ti
B
182,528 (6) — S
208,957 (5) (7) Al, Mo
249,677 10 5 Co, Cr, Fe
249,772 4 24 Co, Fe
Ba 230,425 — 3 —
233,527 2 0,5 Fe, V
455,403 6 0,7 Zr
493,408 (3) 0,4 -
Be 313,042 (2) (0,1) Fe
313,107 — (0,3) V
234,861 (5) (0,1) —
Bi 223,060 (40) (17) Co, Cu, Ti, V
306,770 (80) (165) Fe, Mo, V
Ca 315,887 100 13 Co, Mo
317,933 26 4 Fe, V
393,366 0,4 25 V, Zr
422,673 — — V, Mo, Zr
Cd 214,441 1 0,9 As, Cr, Fe, Sc, Sb
226,502 4 0,2 As, Co, Fe, Ni
228,802 2 0,5 As, Co, Sc
Co 228,616 6 1 Ti
238,892 10 3 Fe
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Table 1 (continued)
Element Wavelength Approx. X Interfering elements
LQ
Radial viewing Axial viewing
nm µg/l µg/l
Cr 205,559 1 5 Be, Fe, Mo, Ni, Ti
267,719 4 2 Mn, P, V
283,563 (10) (2) Fe, Mo, V, W
284,324 (10) — Fe
Cu
324,754 9 2 Cr, Fe, Mo, Ti
327,396 4 3 Co, Ti
Fe 238,204 14 (3) Co
259,940 6 2 Co
271,441 — — —
Ga
287,424 — — Cr
294,364 — — Fe, Ti
417,204 — — Fe, V
In 230,605 — — Fe
325,609 — — Mn
410,175 — — Ce
K 766,490 66 20 Ar, Ba, Mg
769,896 — (230) Ba
Li 460,290 900 (700) Ar, Fe
670,778 6 10 Ar
Mg 279,078 33 19 Fe
279,553 1 7 Fe
285,213 4 14 Cr
Mn 257,610 1 0,4 Cr, Fe, Mo, W
293,305 (20) (8) Al, Cr, Fe, Ti
Mo 202,031 (30) (2) Al, Fe, Ni
204,597 (50) (6) Co, Cr
Na
330,237 (20) 300 Zn
588,995 20 200 Ar, V
589,592 93 20 Ba
Ni 221,648 10 2 Si
231,604 15 2 Co, Sb
P
177,434 500 (16) Cu
178,221 25 13 Fe, I
213,618 500 50 Co, Cu, Fe, Mo, Zn
214,915 330 9 Al, Co, Cu, Mg
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Table 1 (continued)
Element Wavelength Approx. X Interfering elements
LQ
Radial viewing Axial viewing
nm µg/l µg/l
Pb 220,353 14 5 Al, Co, Fe, Ti
283,305 (70) (20) Cr, Fe
S
180,669 13 33 As, Ca
181,975 39 17 Cr, Mo
Sb 206,834 (100) (4) Co, Cr, Fe, Mg, Mn
217,582 (100) (18) Pb, Fe
Se 196,089 (100) (7) —
203,984 (100) (7) Cr, Sb
Si 212,412 3 (13) Mo
251,611 20 10 —
288,158 (30) 24 Cr
Sn 189,988 (100) (60) Cr, Ti
235,485 (100) (200) Cd, Mo
283,998 — (120)
Sr 407,771 2,6 0,6 Cr
421,552 0,1 0,1 —
460,733 (10) (3) —
Ti
334,941 (5) (2) Cr
336,123 (10) (1) —
337,280 (10) — —
368,521 (10) — Co, Cr
V 290,881 (10) — Fe, Mo
292,402 (10) (3) Cr, Fe, Mo, V
310,229 (10) (0,7) Cr, Mg
311,071 (10) (1) Cr, Fe, Mn, Ti
W 202,998 (60) — Ni, Zn
207,912 (30) (10) Ni, Mo, V
209,860 (60) (20) —
222,589 (60) (30) Cr, Cu, Ni
239,711 (60) — —
Zn 202,548 — (3) Cr, Cu, Co, Ni
206,200 13 5 Cr
213,857 3,3 1 Cu, Fe, Ni
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
Table 1 (continued)
Element Wavelength Approx. X Interfering elements
LQ
Radial viewing Axial viewing
nm µg/l µg/l
Zr 339,197 — (2) Mo
343,823 (10) (0,3) —
354,262 (50) (1) —
NOTE 1 X : Definition of the limit of quantification (X ) according to definition 3.11.
LQ LQ
NOTE 2 Most X data derive from the Interlaboratory trial (see Annex B). Participants were asked to report their
LQ
X calculated according to definition 3.11. In Table 1, the median of the reported data for the matrix drinking water is
LQ
given. Data reported in brackets derive from other sources.
a
Wavelength in Table 1 according to NIST tables for basic atomic spectroscopic data
(http://physics.nist.gov/PhysRefData/Handbook/)
b
As some wavelengths are only recommended for vacuum instruments and not recommended for purged
instruments, the choice of wavelengths for a specific instrument should be carried out with respect to the
manufacturer’s recommendation.
Because of the differences between various models of satisfactory instruments, no detailed instrumental
operating instructions can be provided. Instead, the analyst will need to refer to the instructions provided by
the manufacturer of the particular instrument.
6 Interferences
6.1 General
Several types of interference effects can contribute to inaccuracies in the determination of elements. They are
also termed matrix effects.
In order to avoid interferences, whenever a new or unusual sample matrix is encountered, the method in use
should be carefully reviewed if it is suitable for this type of sample or a new method should be developed. In
order to validate the method, measurements of suitable reference materials are to be carried out. Additionally,
comparison tests may be performed with other analytical techniques such as atomic absorption spectrometry
or ICP-MS.
Interferences can be classified as follows.
6.2 Spectral interferences
6.2.1 General
These types of interferences are caused by light of other elements present in the matrix. The error is additive.
Typically, they cause an erroneously high reading. In the case of background influences, low readings can
also occur. The most important spectral interferences are listed in Table 1.
6.2.2 Spectral overlap
6.2.2.1 Overlap of a spectral line from another element
During method development, the goal is to avoid line overlap by the choice of an alternate, undisturbed line. If
this is not possible, these effects can be compensated by utilizing computer correction of the raw data.
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SIST EN ISO 11885:2009
ISO 11885:2007(E)
6.2.2.2 Unresolved overlap of molecular band spectra
If possible, an undisturbed line should be chosen. If this is not possible, these effects can be compensated by
utilizing computer correction of the raw data.
6.2.3 Background influences
Background influences include
1) background contribution from continuous or recombination phenomena, and
2) background contribution from stray light generated from the line emission of high concentration
elements.
The effect of background interferences can usually be compensated by background correction adjacent to the
analyte line.
6.2.4 Detecting spectral interferences
If the peak shape changes in comparison to the peak shape generated by a single element solution, line
overlap can be suspected. Background changes are best identified by overlaying spectra of blank, standards
and samples. Also, the comparison of results for a given element measured at different lines will indicate
spectral interferences.
6.3 Non-spectral interferences
6.3.1 Physical interferences
These are generally considered to be effects associated with the sample nebulization and other transport
processes of the sample from the sample container to the plasma.
They are caused by the change in viscosity, density and/or surface tension. They may result in significant
errors especially in samples containing high dissolved solids and/or acid concentrations. These types of
interferences can be reduced by matrix-matching (if the concentrations of the analytes are high enough,
dilution of the sample may be the preferred way), the use of an internal standard (provided no excitation
interferences are encountered) an
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