Measurement of radioactivity in the environment - Soil - Part 3: Test method of gamma-emitting radionuclides using gamma-ray spectrometry (ISO 18589-3:2015, Corrected version 2015-12-01)

ISO 18589-3:2015 specifies the identification and the measurement of the activity in soils of a large number of gamma-emitting radionuclides using gamma spectrometry. This non-destructive method, applicable to large-volume samples (up to about 3 000 cm3), covers the determination in a single measurement of all the γ-emitters present for which the photon energy is between 5 keV and 3 MeV.
ISO 18589-3:2015 can be applied by test laboratories performing routine radioactivity measurements as a majority of gamma-emitting radionuclides is characterized by gamma-ray emission between 40 keV and 2 MeV.
The method can be implemented using a germanium or other type of detector with a resolution better than 5 keV.
ISO 18589-3:2015 is addressed to people responsible for determining gamma-emitting radionuclides activity present in soils for the purpose of radiation protection.

Ermittlung der Radioaktivität in der Umwelt - Erdboden - Teil 3: Messung von Gammastrahlen emittierenden Radionukliden mittels Gammaspektrometrie (ISO 18589-3:2015, korrigierte Fassung 2015-12-01)

Mesurage de la radioactivité dans l'environnement - Sol - Partie 3: Méthode d'essai des radionucléides émetteurs gamma par spectrométrie gamma (ISO 18589-3:2015, Version corrigée 2015-12-01)

L'ISO 18589-3:2015 spécifie l'identification et le mesurage de l'activité d'un grand nombre de radionucléides émetteurs gamma, dans des sols, par spectrométrie gamma. Cette méthode non destructive applicable à des échantillons de grand volume (jusqu'à 3 000 cm3) permet de déterminer, par un seul mesurage, tous les émetteurs γ présents dont l'énergie des photons est comprise entre 5 keV et 3 MeV.
L'ISO 18589-3:2015 peut être utilisée par les laboratoires d'essai réalisant des mesures de radioactivité en routine, car la majorité des radionucléides émetteurs gamma est caractérisée par des raies d'émission gamma entre 40 keV et 2 MeV.
Cette méthode peut être mise en ?uvre en utilisant un germanium ou un autre type de détecteur d'une résolution supérieure à 5 keV.
L'ISO 18589-3:2015 s'adresse aux personnes chargées de déterminer l'activité des radionucléides émetteurs gamma présents dans les sols dans un but de radioprotection.

Merjenje radioaktivnosti v okolju - Tla - 3. del: Preskusna metoda za radionuklide, ki sevajo žarke gama, s spektrometrijo gama (ISO 18589-3:2015)

Standard ISO 18589-3:2015 določa prepoznavanje in merjenje aktivnosti velikega števila radionuklidov, ki sevajo gama žarke, v prsteh z gama spektrometrijo. Ta nedestruktivna metoda, ki se uporablja za vzorce z veliko prostornino (do približno 3000 cm3), se uporablja za določanje vseh prisotnih sevalnikov žarkov γ s fotonsko energijo med 5 keV in 3 MeV z enim merjenjem.
Standard ISO 18589-3:2015 lahko uporabljajo preskusni laboratoriji, ki izvajajo rutinske meritve radioaktivnosti, saj je za večino radionuklidov, ki sevajo gama žarke, značilno sevanje gama žarkov med 40 keV in 2 MeV.
Metodo se lahko izvaja z germanijem ali drugo vrsto detektorja z ločljivostjo, boljšo od 5 keV.
Standard ISO 18589-3:2015 je namenjen osebam, ki so odgovorne za določanje aktivnosti radionuklidov, ki sevajo gama žarke in so prisotni v prsti, za namene zaščite pred sevanjem.

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Publication Date
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6060 - Definitive text made available (DAV) - Publishing
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SLOVENSKI STANDARD
SIST EN ISO 18589-3:2017
01-december-2017

Merjenje radioaktivnosti v okolju - Tla - 3. del: Preskusna metoda za radionuklide,

ki sevajo žarke gama, s spektrometrijo gama (ISO 18589-3:2015)

Measurement of radioactivity in the environment - Soil - Part 3: Test method of gamma-

emitting radionuclides using gamma-ray spectrometry (ISO 18589-3:2015)
Ermittlung der Radioaktivität in der Umwelt - Erdboden - Teil 3: Messung von
Gammastrahlen emittierenden Radionukliden mittels Gammaspektrometrie (ISO 18589-
3:2015)

Mesurage de la radioactivité dans l'environnement - Sol - Partie 3: Méthode d'essai des

radionucléides émetteurs gamma par spectrométrie gamma (ISO 18589-3:2015)
Ta slovenski standard je istoveten z: EN ISO 18589-3:2017
ICS:
13.080.99 Drugi standardi v zvezi s Other standards related to
kakovostjo tal soil quality
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 18589-3:2017 en,fr,de

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

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SIST EN ISO 18589-3:2017
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SIST EN ISO 18589-3:2017
EN ISO 18589-3
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2017
EUROPÄISCHE NORM
ICS 17.240; 13.080.01
English Version
Measurement of radioactivity in the environment - Soil -
Part 3: Test method of gamma-emitting radionuclides
using gamma-ray spectrometry (ISO 18589-3:2015,
Corrected version 2015-12-01)

Mesurage de la radioactivité dans l'environnement - Ermittlung der Radioaktivität in der Umwelt -

Sol - Partie 3: Méthode d'essai des radionucléides Erdboden - Teil 3: Messung von Gammastrahlen

émetteurs gamma par spectrométrie gamma (ISO emittierenden Radionukliden mittels

18589-3:2015, Version corrigée 2015-12-01) Gammaspektrometrie (ISO 18589-3:2015, korrigierte

Fassung 2015-12-01)
This European Standard was approved by CEN on 13 September 2017.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,

Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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

© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18589-3:2017 E

worldwide for CEN national Members.
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SIST EN ISO 18589-3:2017
EN ISO 18589-3:2017 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO 18589-3:2017
EN ISO 18589-3:2017 (E)
European foreword

The text of ISO 18589-3:2015, Corrected version 2015-12-01 has been prepared by Technical

Committee ISO/TC 85 “Nuclear energy, nuclear technologies, and radiological protection” of the

International Organization for Standardization (ISO) and has been taken over as EN ISO 18589-3:2017

by Technical Committee CEN/TC 430 “Nuclear energy, nuclear technologies, and radiological

protection” the secretariat of which is held by AFNOR.

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 April 2018, and conflicting national standards shall be

withdrawn at the latest by April 2018.

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 organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,

France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,

Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 18589-3:2015, Corrected version 2015-12-01 has been approved by CEN as EN ISO

18589-3:2017 without any modification.
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SIST EN ISO 18589-3:2017
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SIST EN ISO 18589-3:2017
INTERNATIONAL ISO
STANDARD 18589-3
Second edition
2015-02-15
Corrected version
2015-12-01
Measurement of radioactivity in the
environment — Soil —
Part 3:
Test method of gamma-emitting
radionuclides using gamma-ray
spectrometry
Mesurage de la radioactivité dans l’environnement — Sol —
Partie 3: Méthode d’essai des radionucléides émetteurs gamma par
spectrométrie gamma
Reference number
ISO 18589-3:2015(E)
ISO 2015
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form

or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior

written permission. Permission can be requested from either ISO at the address below or ISO’s member body in the country of

the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms, definitions and symbols ............................................................................................................................................................ 2

3.1 Terms and definitions ....................................................................................................................................................................... 2

3.2 Symbols ......................................................................................................................................................................................................... 2

4 Principle ........................................................................................................................................................................................................................ 2

5 Gamma-spectrometry equipment ...................................................................................................................................................... 3

6 Sample container ................................................................................................................................................................................................. 4

7 Procedure..................................................................................................................................................................................................................... 4

7.1 Packaging of samples for measuring purposes ........................................................................................................... 4

7.2 Laboratory background level ..................................................................................................................................................... 5

7.3 Calibration .................................................................................................................................................................................................. 5

7.3.1 Energy calibration .......................................................................................................................................................... 5

7.3.2 Efficiency calibration.................................................................................................................................................... 5

7.4 Measurements of and corrections for natural radionuclides ......................................................................... 6

8 Expression of results ........................................................................................................................................................................................ 6

8.1 Calculation of the activity per unit of mass .................................................................................................................... 6

8.1.1 General...................................................................................................................................................................................... 6

8.1.2 Decay corrections ............................................................................................................................................................ 7

8.1.3 Self-absorption correction ...................................................................................................................................... 7

8.1.4 Summation effects or coincidence losses corrections ..................................................................... 8

8.2 Standard uncertainty ......................................................................................................................................................................... 8

8.3 Decision threshold ............................................................................................................................................................................... 9

8.4 Detection limit ......................................................................................................................................................................................... 9

8.5 Confidence limits................................................................................................................................................................................10

8.6 Corrections for contributions from other radionuclides and background ......................................10

8.6.1 General...................................................................................................................................................................................10

8.6.2 Contribution from other radionuclides .....................................................................................................10

8.6.3 Contribution from background ........................................................................................................................12

9 Test report ................................................................................................................................................................................................................12

Annex A (informative) Calculation of the activity per unit mass from a gamma spectrum

using a linear background subtraction ......................................................................................................................................14

Annex B (informative) Analysis of natural radionuclides in soil samples using

gamma spectrometry ....................................................................................................................................................................................16

Bibliography .............................................................................................................................................................................................................................22

© ISO 2015 – All rights reserved iii
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(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 on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical

Barriers to Trade (TBT), see the following URL: Foreword — Supplementary information.

The committee responsible for this document is ISO/TC 85, Nuclear energy, nuclear technologies, and

radiological protection, Subcommittee SC 2, Radiological protection.

This second edition cancels and replaces the first edition (ISO 18589-3:2007), which has been

technically revised.

ISO 18589 consists of the following parts, under the general title Measurement of radioactivity in the

environment — Soil:
— Part 1: General guidelines and definitions

— Part 2: Guidance for the selection of the sampling strategy, sampling and pre-treatment of samples

— Part 3: Test method of gamma-emitting radionuclides using gamma-ray spectrometry

— Part 4: Measurement of plutonium isotopes (plutonium 238 and plutonium 239 + 240) by alpha spectrometry

— Part 5: Measurement of strontium 90
— Part 6: Measurement of gross alpha and gross beta activities
— Part 7: In situ measurement of gamma-emitting radionuclides

This corrected version of ISO 18589-3:2015 incorporates a correction to Formula (4).

iv © ISO 2015 – All rights reserved
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(E)
Introduction

This part of ISO 18589 is published in several parts to be used jointly or separately according to needs.

ISO 18589-1 to ISO 18589-6, concerning the measurements of radioactivity in the soil, have been

prepared simultaneously. These parts are complementary and are addressed to those responsible for

determining the radioactivity present in soils. The first two parts are general in nature. ISO 18589-3

to ISO 18589-5 deal with radionuclide-specific measurements and ISO 18589-6 with non-specific

measurements of gross alpha or gross beta activities. ISO 18589-7 deals with the measurement of

gamma-emitting radionuclides using in situ spectrometry.

Additional parts can be added to ISO 18589 in the future if the standardization of the measurement of

other radionuclides becomes necessary.
© ISO 2015 – All rights reserved v
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SIST EN ISO 18589-3:2017
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SIST EN ISO 18589-3:2017
INTERNATIONAL STANDARD ISO 18589-3:2015(E)
Measurement of radioactivity in the environment — Soil —
Part 3:
Test method of gamma-emitting radionuclides using
gamma-ray spectrometry
1 Scope

This part of ISO 18589 specifies the identification and the measurement of the activity in soils of a large

number of gamma-emitting radionuclides using gamma spectrometry. This non-destructive method,

applicable to large-volume samples (up to about 3 000 cm ), covers the determination in a single

measurement of all the γ-emitters present for which the photon energy is between 5 keV and 3 MeV.

This part of ISO 18589 can be applied by test laboratories performing routine radioactivity

measurements as a majority of gamma-emitting radionuclides is characterized by gamma-ray emission

between 40 keV and 2 MeV.

The method can be implemented using a germanium or other type of detector with a resolution

better than 5 keV.

This part of ISO 18589 is addressed to people responsible for determining gamma-emitting radionuclides

activity present in soils for the purpose of radiation protection. It is suitable for the surveillance of the

environment and the inspection of a site and allows, in case of accidents, a quick evaluation of gamma

activity of soil samples. This might concern soils from gardens, farmland, urban or industrial sites that

can contain building materials rubble, as well as soil not affected by human activities.

When the radioactivity characterization of the unsieved material above 200 μm or 250 μm, made of

petrographic nature or of anthropogenic origin such as building materials rubble, is required, this

material can be crushed in order to obtain a homogeneous sample for testing as described in ISO 18589-2.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 10703, Water quality — Determination of the activity concentration of radionuclides — Method by

high resolution gamma-ray spectrometry
ISO 11074, Soil quality — Vocabulary

ISO 11929, Determination of the characteristic limits (decision threshold, detection limit and limits of the

confidence interval) for measurements of ionizing radiation — Fundamentals and application

ISO 18589-1, Measurement of radioactivity in the environment — Soil — Part 1: General guidelines

and definitions

ISO 18589-2, Measurement of radioactivity in the environment — Soil — Part 2: Guidance for the selection

of the sampling strategy, sampling and pre-treatment of samples
ISO 80000-10, Quantities and units — Part 10: Atomic and nuclear physics

IEC 61452, Nuclear instrumentation — Measurement of gamma-ray emission rates of radionuclides —

Calibration and use of germanium spectrometer
© ISO 2015 – All rights reserved 1
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(E)

ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories

3 Terms, definitions and symbols
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 10703, ISO 11074, ISO 18589-1

and ISO 80000-10 apply.
3.2 Symbols
m mass of the test portion, in kilograms

A activity of each radionuclide in the calibration source, at the calibration time, in becquerel

a, a activity, in becquerel per kilogram, per unit of mass of each radionuclide, without and with

corrections
t sample spectrum counting time, in seconds
t ambient background spectrum counting time, in seconds
t calibration spectrum counting time, in seconds

n , n , n number of counts in the net area of the peak, at energy, E, in the sample spectrum, in the

N,E N0,E Ns,E
background spectrum and in the calibration spectrum, respectively

n , n , n number of counts in the gross area of the peak, at energy, E, in the sample spectrum, in the

g,E g0,E gs,E
background spectrum and in the calibration spectrum, respectively

n , n , n number of counts in the background of the peak, at energy, E, in the sample spectrum, in

b,E b0,E bs,E
the background spectrum and in the calibration spectrum, respectively
ε efficiency of the detector at energy, E, with the actual measurement geometry

P probability of the emission of gamma radiation with energy, E, for each radionuclide, per

decay

μ(E), μ (E) linear attenuation coefficient at photon energy, E, of the sample and calibration source,

1 2
respectively, per centimetre

μ (E) mass attenuation coefficient, in square centimetres per gram, at photon energy, E, of ele-

m,i
ment i
h height of the sample in the container, in centimetres
w mass fraction of element i (no unit)
ρ bulk density, in grams per cubic centimetre, of the sample
λ decay constant of each radionuclide, per second

u(a), u(a ) standard uncertainty, in becquerel per kilogram, associated with the measurement result,

with and without corrections, respectively

U expanded uncertainty, in becquerel per kilogram, calculated by U = k u (a) with k = 1, 2, …

decision threshold, in becquerel per kilogram, for each radionuclide, without and with

aa,
corrections, respectively

detection limit, in becquerel per kilogram, for each radionuclide, without and with correc-

aa,
c tions, respectively

lower and upper limits of the confidence interval, for each radionuclide, in becquerel per

aa,
kilogram
4 Principle

The activity of gamma-emitting radionuclides present in the soil samples is determined using gamma

spectrometry techniques based on the analysis of the energies and the peak areas of the full-energy

2 © ISO 2015 – All rights reserved
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SIST EN ISO 18589-3:2017
ISO 18589-3:2015(E)

peaks of the gamma lines. These techniques allow the identification and the quantification of the

[1][2]
radionuclides.

The nature and geometry of the detectors as well as the samples call for appropriate energy and

[1][2]

efficiency calibrations. Both coincidence and random summation effects need to be considered,

particularly with container sitting directly on the detector and Marinelli type container, high activity

levels or with well-type detectors used to measure small-mass samples (see 8.1.4).

NOTE ISO 18589 deals exclusively with gamma spectrometry using semiconductor detectors.

5 Gamma-spectrometry equipment
Gamma-spectrometry equipment generally consists of

— a semiconductor detector with a cooling system (liquid nitrogen, cryogenic assembly, etc.),

— a shield, consisting of lead and/or other materials, against ambient radiation,

— appropriate electronics (high-voltage power supply; signal-amplification system; an analogue-to-

digital converter),
— a multi-channel amplitude analyser, and
— a computer to display the measurement spectra and to process the data.

The semiconductor detectors generally used are made of high-purity germanium crystals (HP Ge). The

type and geometry of these detectors determine their field of application. For example, when detecting

photons with an energy below 400 keV, the use of detectors with a thin crystal is recommended in

order to limit interference from high-energy photons. However, it is better to use a large-volume, P-type

coaxial detector to measure high-energy photons (above 200 keV) or an N-type coaxial detector to

detect both low- and high-energy radiation.

At the level of natural radioactivity, it is advantageous for the measurement to use an ultra-low-level

measuring instrument, i.e. a set-up arranged with a choice of materials for the detector and shielding

that guarantees a very low background level. This includes very low-noise electronic preamplifiers and

amplifiers. The shielding case should be large enough to allow sufficient distance from all walls and the

detector set up in the centre of the case, when 1-l samples are inserted. This allows the use of a room

with a very low specific activity of building materials and a very low radon concentration in the room

air to be chosen. It is optimal to erect the measuring instruments in the middle of the room with the

maximum distance available to the room walls. Forced ventilation of the measuring room can possibly

contribute to stabilizing the background level. On the other hand, forced ventilation can then cause

problems when the outside air drawn in contains excess radon as a result of a warming-up of the soil

(in particular, when the soil thaws in spring). It is always good practice to fill the inner part of the

shielding with nitrogen. For this, the gaseous nitrogen escaping from the Dewar vessel of the detector

arrangement can be passed permanently into the shielding.

The main characteristics that allow the estimation of a detector performance are as follows:

a) energy resolution (total width at half maximum of the full-energy peak), which enables the detector

to separate two neighbouring gamma peaks;

b) absolute efficiency, which specifies the percentage of photons detected in the full-energy peak

relative to the number of photons emitted;
c) peak-to-Compton ratio.

Depending on the required accuracy and the desired detection limit, it is generally necessary to use

high-quality detectors whose energy resolution is less than 2,2 keV (for the Co peak at 1 332 keV) and

137
with a peak/Compton ratio between 50 and 80 for Cs (see IEC 61452).
© ISO 2015 – All rights reserved 3
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ISO 18589-3:2015(E)
210 238 234

Some natural radionuclides, e.g. Pb and U through Th, can be measured only through gamma

lines in the energy range of 100 keV. In this case, the use of an N-type detector is recommended. Low-

energy, low-level detectors offered by manufacturers have been optimized for this purpose and can

129

additionally be used in other areas of environmental monitoring, e. g. for measurements of I and

241
Am in samples from the vicinity of nuclear facilities.
[5][6]

The computer, in combination with the available hardware and software, shall be carefully selected.

It is recommended that the results of the computer analysis of the spectrum be visually checked regularly.

Comparison with a certified reference material is recommended to check the performance of the

apparatus. Participation in proficiency and inter-laboratory tests and inter-comparison exercises can

[9][10]

also help to verify the performance of the apparatus and the status of the analysis.

6 Sample container

Measuring gamma radioactivity in soils requires sample containers that are suited to gamma

spectrometry with the following recommended characteristics:
— be made of materials with low absorption of gamma radiation;
— be made of transparent material to see the level of content;
— have volumes adapted to the shape of the detector for maximum efficiency;
— be watertight and not react with the sample constituents;
— have a wide-necked, airtight opening to facilitate filling;
— be unbreakable.

In order to verify easily that the content of the container conforms to the standard counting geometry,

a transparent container with a mark to check the filling can be selected.
7 Procedure
7.1 Packaging of samples for measuring purposes

The soil samples packaged for gamma spectrometry measurements are usually dried, crushed, and

homogenized in accordance with ISO 18589-2.
The procedure shall be carried out as follows.

a) Choose the container that is best suited to the volume of the sample so as to measure as much material

as possible. To decrease self-absorption effects, the height of the contents should be minimized.

b) Fill the container to the level of the volume mark. It is recommended to use a mechanical filling

device (for example, a vibrating table) to pack the sample to avoid any future losses in volume.

c) Note t
...

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