oSIST prEN ISO 13165-3:2023
(Main)Water quality - Radium-226 - Part 3: Test method using coprecipitation and gamma-spectrometry (ISO/DIS 13165-3:2023)
Water quality - Radium-226 - Part 3: Test method using coprecipitation and gamma-spectrometry (ISO/DIS 13165-3:2023)
ISO 13165-3:2016 specifies the determination of radium-226 (226Ra) activity concentration in all types of water by coprecipitation followed by gamma-spectrometry (see ISO 18589‑3).
The method described is suitable for determination of soluble 226Ra activity concentrations greater than 0,02 Bq l−1 using a sample volume of 1 l to 100 l of any water type.
For water samples smaller than a volume of 1 l, direct gamma-spectrometry can be performed following ISO 10703 with a higher detection limit.
NOTE This test method also allows other isotopes of radium, 223Ra, 224Ra, and 228Ra, to be determined.
Wasserbeschaffenheit - Radium-226 - Teil 3: Verfahren mittels Kopräzipitation und Gammaspektrometrie (ISO/DIS 13165-3:2023)
Qualité de l'eau - Radium 226 - Partie 3: Méthode d'essai par co-précipitation et spectrométrie gamma (ISO/DIS 13165-3:2023)
L'ISO 13165-3:2016 spécifie la détermination de l'activité volumique du radium 226 (226Ra), dans tous les types d'eaux par coprécipitation suivie d'une spectrométrie gamma (voir l'ISO 18589‑3).
La méthode décrite est applicable pour la détermination de l'activité volumique du 226Ra soluble ayant une activité volumique en 226Ra supérieure à 0,02 Bq l−1 en utilisant un volume d'échantillon compris entre 1 l et 100 l de tout type d'eau.
Pour des échantillons d'eau inférieurs à un volume de 1 l, la spectrométrie gamma directe peut être effectuée en se conformant à l'ISO 10703 avec une limite de détection supérieure.
NOTE Cette méthode d'essai permet également le mesurage d'autres isotopes du radium (223Ra, 224Ra et 228Ra).
Kakovost vode - Radij Ra-226 - 3. del: Preskusna metoda s soobarjanjem in gama spektrometrijo (ISO/DIS 13165-3:2023)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN ISO 13165-3:2023
01-maj-2023
Kakovost vode - Radij Ra-226 - 3. del: Preskusna metoda s soobarjanjem in gama
spektrometrijo (ISO/DIS 13165-3:2023)
Water quality - Radium-226 - Part 3: Test method using coprecipitation and gamma-
spectrometry (ISO/DIS 13165-3:2023)
Wasserbeschaffenheit - Radium-226 - Teil 3: Verfahren mittels Kopräzipitation und
Gammaspektrometrie (ISO/DIS 13165-3:2023)
Qualité de l'eau - Radium 226 - Partie 3: Méthode d'essai par co-précipitation et
spectrométrie gamma (ISO/DIS 13165-3:2023)
Ta slovenski standard je istoveten z: prEN ISO 13165-3
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
oSIST prEN ISO 13165-3:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 13165-3:2023
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oSIST prEN ISO 13165-3:2023
DRAFT INTERNATIONAL STANDARD
ISO/DIS 13165-3
ISO/TC 147/SC 3 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2023-03-16 2023-06-08
Water quality — Radium-226 —
Part 3:
Test method using coprecipitation and gamma-
spectrometry
Qualité de l'eau — Radium 226 —
Partie 3: Méthode d'essai par coprécipitation et spectrométrie gamma
ICS: 17.240; 13.060.60
This document is circulated as received from the committee secretariat.
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 13165-3
ISO/TC 147/SC 3 Secretariat: AFNOR
Voting begins on: Voting terminates on:
Water quality — Radium-226 —
Part 3:
Test method using coprecipitation and gamma-
spectrometry
Qualité de l'eau — Radium 226 —
Partie 3: Méthode d'essai par coprécipitation et spectrométrie gamma
ICS: 17.240; 13.060.60
This document is circulated as received from the committee secretariat.
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Principle of the measurement .3
6 Reagents and equipment . 3
6.1 Reagents . 3
6.2 Equipment . 4
7 Sampling . 4
7.1 Sample collection . . . 4
7.2 Sample transport and storage . 4
8 Procedures . 5
8.1 Blank sample preparation . 5
8.2 Sample preparation . 5
8.3 Counting procedure . 5
9 Quality assurance and quality control programme . 6
9.1 General . 6
9.2 Influence quantities . 6
9.3 Method verification . 6
9.4 Demonstration of analyst capability . 6
10 Expression of results . 7
10.1 General . 7
226
10.2 Water-soluble Ra activity concentration . 7
10.3 Standard uncertainty of activity concentration . 7
10.4 Decision threshold . 8
10.5 Detection limit . 8
10.6 Limits of the coverage intervals . . 8
10.6.1 Limits of the probabilistically symmetric coverage interval . 8
10.6.2 The shortest coverage interval . 9
10.7 Corrections for contributions from other radionuclides and background . 9
10.7.1 General . 9
10.7.2 Contribution from other radionuclides . 10
10.7.3 Contribution from background . 11
11 Test report .11
Annex A (informative) Uranium, Thorium and Neptunium and their decay chains .13
Bibliography .15
iii
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 147 Water quality, Subcommittee SC 3,
Radioactivity measurements.
This second edition cancels and replaces the first edition (ISO 13165-3:2016), which has been
technically revised.
The main changes are as follows:
— complete revision of the introduction
— the principal of measurement (Clause 5) was expanded
— the instrument verification (formerly subclause 9.3) was deleted
— formulae for the coverage intervals according to ISO 11929 series were updated
— requirements of the test report were updated
A list of all parts in the ISO 13165 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
Introduction
Radionuclides are present throughout the environment; thus, water bodies (e.g., surface waters, ground
waters, sea waters) contain radionuclides, which can be of either natural or anthropogenic origin:
3 14 40
— naturally-occurring radionuclides, including H, C, K and those originating from the thorium
210 210 222 226 228 227 231
and uranium decay series (see Annex A), in particular Pb, Po, Rn, Ra, Ra, Ac, Pa,
234 238
U, and U, can be found in water bodies due to either natural processes (e.g. desorption from the
soil, runoff by rain water) or released from technological processes involving naturally occurring
radioactive materials (e.g. mining, mineral processing, oil, gas, and coal production, water treatment
and the production and use of phosphate fertilisers);
55 59 63 90 99
— anthropogenic radionuclides such as Fe, Ni, Ni, Sr, Tc, transuranic elements (e.g., Np,
60 137
Pu, Am, and Cm), and some gamma emitting radionuclides such as Co and Cs can also be
found in natural waters. Small quantities of anthropogenic radionuclides can be discharged from
nuclear facilities to the environment as a result of authorized routine releases. The radionuclides
[1]
present in liquid effluents are usually controlled before being discharged to the environment
and water bodies. Anthropogenic radionuclides used in medical and industrial applications can be
released to the environment after use. Anthropogenic radionuclides are also found in waters due to
contamination from fallout resulting from above-ground nuclear detonations and accidents such as
those that have occurred at the Chornobyl and Fukushima nuclear facilities.
Radionuclide activity concentrations in water bodies can vary according to local geological
characteristics and climatic conditions and can be locally and temporally enhanced by releases from
[2][3]
nuclear facilities during planned, existing, and emergency exposure situations. Some drinking
water sources can thus contain radionuclides at activity concentrations that could present a human
health risk. The World Health Organization (WHO) recommends to routinely monitor radioactivity in
[4]
drinking waters and to take proper actions when needed to minimize the health risk.
National regulations usually specify the activity concentration limits that are authorized in drinking
waters, water bodies, and liquid effluents to be discharged to the environment. These limits can vary
for planned, existing, and emergency exposure situations. As an example, during either a planned or
226 −1
existing situation, the WHO guidance level for Ra in drinking water is 1 Bq·l , see NOTE. Compliance
with these limits is assessed by measuring radioactivity in water samples and by comparing the results
[5] [6]
obtained, with their associated uncertainties, as specified by ISO/IEC Guide 98-3 and ISO 5667-20 .
NOTE The guidance level calculated in Reference [4] is the activity concentration that, with an intake of
−1 −1
2 l·d of drinking water for one year, results in an effective dose of 0,1 mSv·a to members of the public. This is
an effective dose that represents a very low level of risk to human health and which is not expected to give rise to
[4]
any detectable adverse health effects .
226
This document contains method(s) to determine Ra in water samples. It has been developed to
226
support laboratories that need either a certification or accreditation to determine Ra in water
samples. A certification or accreditation are sometimes required by local and national authorities as
well as some customers. The certification and accreditation are provided by an independent body
The method described in this document can be used for various types of waters (see Clause 1). Minor
modifications such as sample volume and counting time can be made if needed to ensure that the
characteristic limit, decision threshold, detection limit, and uncertainties are below the required limits.
This can be done for several reasons such as emergency situations, lower national guidance limits, and
operational requirements.
This document is one of a set of International Standards on test methods dealing with the measurement
of the activity concentration of radionuclides in water samples.
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oSIST prEN ISO 13165-3:2023
DRAFT INTERNATIONAL STANDARD ISO/DIS 13165-3:2023(E)
Water quality — Radium-226 —
Part 3:
Test method using coprecipitation and gamma-
spectrometry
WARNING — Persons using this document should be familiar with normal laboratory practice.
This document 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
determine the applicability of any other restrictions.
IMPORTANT — It is absolutely essential that tests conducted according to this document be
carried out by suitably trained staff.
1 Scope
226
This part of ISO 13165 specifies the determination of radium-226 ( Ra) activity concentration in all
[7]
types of water by coprecipitation followed by gamma-spectrometry (see ISO 18589-3 ).
226
The method described is suitable for determination of soluble Ra activity concentrations greater
−1
than 0,02 Bq l using a sample volume of up to 100 l of any water type.
For water samples smaller than a volume of 1 l, direct gamma-spectrometry can be performed following
ISO 10703with a higher detection limit.
NOTE This test method can be adapted to determine other naturally occurring isotopes of radium, such as
223 224 228
Ra, Ra, and Ra if the respective ingrowth periods are taken into account.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 5667-3, Water quality — Sampling — Part 3: Preservation and handling of water samples
ISO 10703, Water quality — Determination of the activity concentration of radionuclides — Method by
high resolution gamma-ray spectrometry
ISO 11929 (all parts), Determination of the characteristic limits (decision threshold, detection limit and
limits of the confidence interval) for measurements of ionizing radiation — Fundamentals and application
ISO 12749 (all parts), Nuclear energy — Vocabulary
ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12749 and ISO 80000-10 and
the following apply.
1
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
activity
number of spontaneous nuclear disintegrations occurring in a given quantity of material during a
suitably small interval of time divided by that interval of time
3.2
reference standard
standard, generally having the highest metrological quality available at a given location or in a given
organisation, from which measurements made there are derived
3.3
working standard
standard which, usually calibrated against a reference standard (3.2), is used routinely to calibrate or
check material measures, measuring instruments or reference materials. It can be used as a solution of
known activity (3.1) concentration obtained by precise dilution or dissolution of a reference standard
4 Symbols
For the purposes of this document, the following symbols apply.
Table 1 — List of symbols
V Volume of the test sample l
Activity of each radionuclide in calibration source, at the calibration Bq
A
time
226 -1
c Activity concentration of Ra, without and with corrections Bq·l
A
M Mass of barium sulfate g
sulfate
M Mass of barium nitrate g
nitrate
M Mass of barium carbonate g
carbonate
t Sample spectrum counting time s
g
t Background spectrum counting time s
0
Number of counts in the net area of the peak considered, at energy E, in
n , n
N,E N0,E
the sample, background, respectively
Number of counts in the gross area of the peak considered, at energy E,
n , n
g,E g0,E
in the sample, background, respectively
Number of counts in the background of the peak considered, at energy
n , n
b,E b0,E
E, in the sample, background, respectively
ε Detection efficiency at energy, E, at actual measurement geometry
E
f Correction factor considering all necessary corrections
E
R Chemical yield
C
P Probability of the emission of a gamma-ray with energy E of each radio-
E
nuclide, per decay
-1
λ Decay constant of each radionuclide s
-1
u(c ) Standard uncertainty associated with the measurement result (without Bq·l
A
and with corrections) and with fitting efficiency curve respectively
-1
U Expanded uncertainty calculated with k = 2. Bq·l
-1
* Decision threshold, without and with corrections Bq·l
c
A
2
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
-1
#
Detection limit, without and with corrections Bq·l
c
A
-1
Lower and upper limits of the probabilistically symmetric coverage Bq·l
cc,
AA
interval
-1
<> Lower and upper limits of the shortest coverage interval Bq·l
cc,
AA
5 Principle of the measurement
226
Measurement of Ra activity concentration in water is carried out in two separate steps: a sample
[8][9]
preparation step, followed by a measurement by gamma-spectrometry .
After filtration and acidification of the water sample (see ISO 5667-3), to ensure the measurement of the
226 226
activity concentration of the Ra soluble fraction, the Ra is coprecipitated as its sulfate salt using
a barium carrier. The radium and barium sulfates are then washed, dried, and weighed. The chemical
yield is obtained gravimetrically.
For water samples that may have an existing concentration of soluble barium, another tracer should be
used to avoid a chemical yield above 100 %.
133
When a radiometric tracer, such as Ba is used as an internal standard to assess the recovery yield,
then this recovery yield is used instead of R in the Formulae (2) and (4).
c
226
The Ra activity concentration of the precipitate is measured by gamma-spectrometry using a high
purity germanium detector with low system background.
226 214
Secular equilibrium between radon and its progeny is a prerequisite when measuring Ra using Bi
214
and Pb gamma energies. The equilibrium is reached four weeks after the last coprecipitation step.
The equilibrium condition necessitates the sample container to be air-tight.
235
The presence of other gamma emitters, such as U, in the precipitate can interfere with the
226
quantification of Ra activity.
NOTE Since the coprecipitation described in this test method doesn’t discriminate against specific radium
223 224
isotopes, it can be adapted to determine other naturally occurring isotopes of radium, such as Ra, Ra, and
228
Ra if the respective ingrowth periods are taken into account. For this method, however, the equilibrium time
223 224 228
of 4 weeks does not allow for determination of Ra, Ra or Ra.
6 Reagents and equipment
6.1 Reagents
Unless otherwise stated, use only reagents of recognized analytical grade and distilled or demineralized
[10]
water or water of equivalent purity and no undesirable radioactivity (ISO 3696) .
−1
6.1.1 Concentrated nitric acid solution (HNO ), 14,5 – 15,5 mol·l .
3
−1
6.1.2 Nitric acid solution (HNO ), diluted to 0,4 mol·l .
3
−1
6.1.3 Nitric acid solution (HNO ), diluted to 3,2 mol·l .
3
−1 2+
6.1.4 Carrier solution, 10,0 g·l ·Ba .
Slowly dissolve barium nitrate Ba(NO ) (19,0 g) or barium carbonate BaCO (14,3 g) in one litre of
3 2 3
nitric acid solution (6.1.2). The salt mass shall be weighed accurately (better than 1 %) and recorded.
3
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ISO/DIS 13165-3:2023(E)
226
It is recommended to use a Ba(NO ) or BaCO reagent with a low Ra activity concentration. The
3 2 3
226
presence of Ra in the reagent shall be controlled using a blank sample prepared with distilled or
demineralized water.
−1
6.1.5 Concentrated sulfuric acid solution (H SO ), 18,3 mol·l .
2 4
6.1.6 Cellulose ester filter of porosity, 0,45 µm.
6.2 Equipment
Usual laboratory equipment and, in particular, the following:
6.2.1 Peristaltic or membrane pump.
6.2.2 Magnetic bar stirrer.
6.2.3 Centrifuge and tubes.
6.2.4 Analytical balance, accuracy 0,1 mg.
6.2.5 Drying oven.
6.2.6 Gas-tight container.
6.2.7 Gamma-spectrometry system, with low background capability.
Major instrument parameters (energy calibration, efficiency calibration as a function of energy, and
background spectrum) shall be periodically checked within a quality assurance programme established
[11]
by the laboratory and following the manufacturer's instructions (see ISO 10703 and ISO 20042 ).
7 Sampling
The method can be used on water samples up to 100 l.
7.1 Sample collection
The sampling conditions shall comply with ISO 5667-3 and ISO 10703. For sampling, polyethylene
−1
bottles should be used, cleaned with 1 mol·l hydrochloric acid, followed by leaching with dilute nitric
acid solution and rinsed with distilled or deionized water (other cleaning treatments may be used if its
effectiveness is demonstrated).
Depending on the elapsed time between sampling and measurement (e.g., if storage is more than
seven days), the sample should be acidified to pH 1 with nitric acid; if particulate matter is removed by
filtration, this shall be carried out before acidification;
The volume of the water sample to collect for measurement depends on the detection limits required.
7.2 Sample transport and storage
The water sample shall be transported and stored according to ISO 5667-3.
When pre-concentration is desired, acidify the filtered sample to between pH 1 and pH 3 with HNO .
3
Acidification of the water sample minimizes the loss of radioactive material from solution by adsorption.
It is advisable to store liquids at lower temperatures.
The test shall be performed as soon as possible.
4
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oSIST prEN ISO 13165-3:2023
ISO/DIS 13165-3:2023(E)
8 Procedures
8.1 Blank sample preparation
Prepare a blank with distilled or demineralized water by performing the operations described in step
a) to i) in 8.2.
8.2 Sample preparation
a) To prevent adsorption effects and proliferation of algae, the water sample is filtered and acidified
to pH 1 with nitric acid (see 6.1.1). The water sample volume can be 1 l to 100 l. Acidification of
...
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