SIST EN ISO 18589-7:2016
(Main)Measurement of radioactivity in the environment - Soil - Part 7: In situ measurement of gamma-emitting radionuclides (ISO 18589-7:2013)
Measurement of radioactivity in the environment - Soil - Part 7: In situ measurement of gamma-emitting radionuclides (ISO 18589-7:2013)
ISO 18589-7:2013 specifies the identification of radionuclides and the measurement of their activity in soil using in situ gamma spectrometry with portable systems equipped with germanium or scintillation detectors.
Ermittlung der Radioaktivität in der Umwelt - Erdboden - Teil 7: In-situ-Messung von Gammastrahlung emittierenden Radionukliden (ISO 18589-7:2013)
Mesurage de la radioactivité dans l'environnement - Sol - Partie 7: Mesurage in situ des radionucléides émetteurs gamma (ISO 18589-7:2013)
L'ISO 18589-7:2013 spécifie l'identification des radionucléides et la quantification de leur activité dans le sol en utilisant la spectrométrie gamma in situ avec des systèmes portatifs équipés de détecteurs au germanium ou à scintillations.
L'ISO 18589-7:2013 est adaptée pour évaluer rapidement l'activité des radionucléides artificiels et naturels déposés ou présents dans des couches du sol d'un site soumis à l'étude.
L'ISO 18589-7:2013 peut être utilisée en relation avec les mesurages de radionucléides des échantillons de sol au laboratoire [ISO 18589‑3] dans les cas suivants pour
la surveillance en routine de l'impact de la radioactivité émanant d'installations nucléaires ou de l'évolution de la radioactivité du territoire,
les investigations en situations d'accidents et d'incidents,
la planification et la surveillance des actions de remédiation, et
le déclassement d'installations ou l'élimination de matières nucléaires.
L'ISO 18589-7:2013 peut également être utilisée pour identifier les radionucléides artificiels dans l'air, lors de l'évaluation des niveaux d'exposition à l'intérieur de bâtiments ou au cours des opérations d'élimination de déchets.
Merjenje radioaktivnosti v okolju - Tla - 7. del: Meritve radionuklidov, ki sevajo žarke gama, na kraju samem (ISO 18589-7:2013)
Standard ISO 18589-7:2013 določa identifikacijo radionuklidov in merjenje njihove aktivnosti v zemljini z gama spektrometrijo na kraju samem s prenosnimi sistemi, opremljenimi z germanijevimi ali scintilacijskimi detektorji.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 18589-7:2016
01-junij-2016
Merjenje radioaktivnosti v okolju - Tla - 7. del: Meritve radionuklidov, ki sevajo
žarke gama, na kraju samem (ISO 18589-7:2013)
Measurement of radioactivity in the environment - Soil - Part 7: In situ measurement of
gamma-emitting radionuclides (ISO 18589-7:2013)
Ermittlung der Radioaktivität in der Umwelt - Erdboden - Teil 7: In-situ-Messung von
Gammastrahlung emittierenden Radionukliden (ISO 18589-7:2013)
Mesurage de la radioactivité dans l'environnement - Sol - Partie 7: Mesurage in situ des
radionucléides émetteurs gamma (ISO 18589-7:2013)
Ta slovenski standard je istoveten z: EN ISO 18589-7:2016
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 18589-7:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 18589-7:2016
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SIST EN ISO 18589-7:2016
EN ISO 18589-7
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2016
EUROPÄISCHE NORM
ICS 17.240; 13.080.01
English Version
Measurement of radioactivity in the environment - Soil -
Part 7: In situ measurement of gamma-emitting
radionuclides (ISO 18589-7:2013)
Mesurage de la radioactivité dans l'environnement - Ermittlung der Radioaktivität in der Umwelt -
Sol - Partie 7: Mesurage in situ des radionucléides Erdboden - Teil 7: In-situ-Messung von
émetteurs gamma (ISO 18589-7:2013) Gammastrahlung emittierenden Radionukliden (ISO
18589-7:2013)
This European Standard was approved by CEN on 21 February 2016.
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, 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: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18589-7:2016 E
worldwide for CEN national Members.
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SIST EN ISO 18589-7:2016
EN ISO 18589-7:2016 (E)
Contents Page
European foreword . 3
2
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SIST EN ISO 18589-7:2016
EN ISO 18589-7:2016 (E)
European foreword
The text of ISO 18589-7:2013 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 18589-7:2016 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 October 2016, and conflicting national standards shall
be withdrawn at the latest by October 2016.
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.
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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 18589-7:2013 has been approved by CEN as EN ISO 18589-7:2016 without any
modification.
3
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SIST EN ISO 18589-7:2016
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SIST EN ISO 18589-7:2016
INTERNATIONAL ISO
STANDARD 18589-7
First edition
2013-10-01
Measurement of radioactivity in the
environment — Soil —
Part 7:
In situ measurement of gamma-
emitting radionuclides
Mesurage de la radioactivité dans l’environnement — Sol —
Partie 7: Mesurage in situ des radionucléides émetteurs gamma
Reference number
ISO 18589-7:2013(E)
©
ISO 2013
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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Published in Switzerland
ii © ISO 2013 – All rights reserved
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols, and units . 2
3.1 Terms and definitions . 2
3.2 Symbols and units . 3
4 Principles . 6
4.1 Measurement method . 6
4.2 Uncertainties of the measurement method . 6
5 Equipment . 6
5.1 Portable in situ spectrometry system . 6
5.2 Detector System . 7
5.3 Pulse processing electronics . 8
5.4 Assembly jig for a detector system . 9
5.5 Collimated detector . 9
6 Procedure.12
6.1 Calibration .12
6.2 Method of combined calibrations .12
7 Quality assurance and quality control program .17
7.1 General .17
7.2 Influencing variables .17
7.3 Instrument verification.17
7.4 Method verification .17
7.5 Quality control program .17
7.6 Standard operating procedure .19
8 Expression of results .19
8.1 Calculation of activity per unit of surface area or unit of mass .19
8.2 Calculation of the characteristic limits and the best estimate of the measurand as well as
its standard uncertainty .19
8.3 Calculation of the radionuclide specific ambient dose rate .21
9 Test report .22
Annex A (informative) Influence of radionuclides in air on the result of surface or mass activity
measured by in situ gamma spectrometry .23
Annex B (informative) Influence quantities .24
Annex C (informative) Characteristics of germanium detectors .27
Annex D (informative) Field-of-view of an in situ gamma spectrometer as a function of the photon
energy for different radionuclide distributions in soil .29
Annex E (informative) Methods for calculating geometry factors and angular correction factors.33
Annex F (informative) Example for calculation of the characteristic limits as well as the best
estimate of the measurand and its standard uncertainty .41
Annex G (informative) Conversion factors for surface or mass activity to air kerma rate and
ambient dose equivalent rate for different radionuclide distribution in soil .45
Annex H (informative) Mass attenuation factors for soil and attenuation factors for air as a
function of photon energy and deviation of G(E,V) for different soil compositions .52
Bibliography .54
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(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. 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. 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.
The committee responsible for this document is ISO/TC 85, Nuclear energy, nuclear technologies, and
radiological protection, Subcommittee SC 2, Radiological protection.
ISO 18589 consists of the following parts, under the general title Measurement of the 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: Measurements of gamma-emitting radionuclides
— 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
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(E)
Introduction
In situ gamma spectrometry is a rapid and accurate technique to assess the activity concentration of
gamma-emitting radionuclides present in the top soil layer or deposited onto the soil surface. This
method is also used to assess the dose rates of individual radionuclides.
In situ gamma spectrometry is a direct physical measurement of radioactivity that does not need any
soil samples, thus reducing the time and cost of laboratory analysis of large number of soil samples.
The quantitative analysis of the recorded line spectra requires a suitable area for the measurement.
Furthermore, it is required to know the physicochemical properties of the soil and the vertical
distribution in the soil to assess the activity of the radionuclides.
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SIST EN ISO 18589-7:2016
INTERNATIONAL STANDARD ISO 18589-7:2013(E)
Measurement of radioactivity in the environment — Soil —
Part 7:
In situ measurement of gamma-emitting radionuclides
1 Scope
This part of 18589 specifies the identification of radionuclides and the measurement of their activity
in soil using in situ gamma spectrometry with portable systems equipped with germanium or
scintillation detectors.
This part of ISO 18589 is suitable to rapidly assess the activity of artificial and natural radionuclides
deposited on or present in soil layers of large areas of a site under investigation.
This part of ISO 18589 can be used in connection with radionuclide measurements of soil samples in the
laboratory (ISO 18589-3) in the following cases:
— routine surveillance of the impact of radioactivity released from nuclear installations or of the
evolution of radioactivity in the region;
— investigations of accident and incident situations;
— planning and surveillance of remedial action;
— decommissioning of installations or the clearance of materials.
It can also be used for the identification of airborne artificial radionuclides, when assessing the exposure
levels inside buildings or during waste disposal operations.
Following a nuclear accident, in situ gamma spectrometry is a powerful method for rapid evaluation of
the gamma activity deposited onto the soil surface as well as the surficial contamination of flat objects.
NOTE The method described in this part of ISO 18589 is not suitable when the spatial distribution of the
radionuclides in the environment is not precisely known (influence quantities, unknown distribution in soil) or in
situations with very high photon flux. However, the use of small volume detectors with suitable electronics allows
measurements to be performed under high photon flux.
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/IEC 17025, General requirements for the competence of testing and calibration laboratories
IEC 61275, Radiation protection instrumentation — Measurement of discrete radionuclides in the
environment — In situ photon spectrometry system using a germanium detector
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
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ISO 18589-7:2013(E)
3 Terms, definitions, symbols, and units
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
intrinsic efficiency
η
0
cross section of a detector for photons from the direction of the crystal symmetry axis
Note 1 to entry: The intrinsic efficiency depends on the energy of the photon.
3.1.2
detector efficiency
η (E)
0
detector efficiency in the direction of the crystal symmetry axis as a function of the photon energy E
3.1.3
detector height
d
distance between the geometrical centre of the crystal and the soil surface
3.1.4
efficiency per unit of surface area or unit of mass
ε
ratio between the net count rate of an absorption line with energy E and the photon emission rate per
unit area or mass
3.1.5
relative detection efficiency
60
ratio, expressed in percentage, of the count rate in the Co 1 333 keV total absorption peak to the one
obtained with a 3 x 3 inch NaI(Tl) scintillator for normal incidence and at 0,25 m from the source
3.1.6
geometry factor
G
ratio between the flux density without scattered photons measured at the detector location and the
photon emission rate per unit area or mass
3.1.7
aperture angle of collimator
ϑ
col
characteristic angle for an in situ gamma spectrometer with collimator
3.1.8
[7]
relaxation mass per unit area
β
mathematical parameter describing radionuclide distribution as a function of soil depth
Note 1 to entry: It indicates the soil mass per unit of surface area at which gamma activity decreases to 1/e (37 %).
3.1.9
field-of-view of a detector
soil surface area, from which 90 % of the unscattered detected photons originate
3.1.10
distribution model
V
entity of all physical and geometrical parameters to describe the distribution of the radionuclide in the
environment as well as the interaction of an emitted photon with soil and air
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(E)
3.1.11
angular coefficient
k
m
factor taking into account the angular response of the detector and the angular distribution of the
incident flux
3.1.12
measurement area
area in the soil and/or on the soil surface having radionuclide activity per unit of surface area or unit of mass
3.1.13
[7]
mass per unit area (collimator)
ζ
col
product of material density and wall thickness of a collimator
Note 1 to entry: The mass per unit area is reported for a polar angle, ϑ, of 90° in relation to the crystal centre.
3.1.14
cross section of the detector
ratio of the net rate of the total absorption line at energy E and the flux density of unscattered photons
of the energy E in the detector
3.1.15
calibration factor per unit of surface area or unit of mass
w
ratio of the activity of surface area or unit of mass of the radionuclide to the net count rate of the total
absorption line
3.2 Symbols and units
For the purposes of this part of ISO 18589, the symbols and units defined in ISO 11929 and given in
Table 1 apply.
Table 1 — Symbols
Symbols Designation Unit
a Activity of a given radionuclide at the time of measurement
-2
a) per unit of surface area Bq ⋅ m
-1
b) per unit of mass Bq ⋅ kg
â
Best estimate of the measurand of the activity of the radionu-
clide in question
-2
a) per unit of surface area Bq ∙ m
-1
b) per unit of mass Bq ∙ kg
a Activity of the calibration standard at the time of measurement Bq
K
-2
a Activity of the radionuclide in question at the soil surface Bq ⋅ m
0
-2
a(ζ) Projected surface activity as a function of mass per unit at the Bq ⋅ m
surface of the soil
a* Decision threshold of the measurand of the radionuclide in ques-
tion at the time of measurement
-2
a) per unit of surface area Bq ⋅ m
-1
b) per unit of mass Bq ∙ kg
#
a Detection limit of the measurand of the radionuclide in question
at the time of measurement
-2
a) per unit of surface area Bq ∙ m
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SIST EN ISO 18589-7:2016
ISO 18589-7:2013(E)
Table 1 (continued)
Symbols Designation Unit
-1
b) per unit of mass Bq ∙ kg
Upper and lower limit of the confidence interval, respectively,
a a
,
of the measurand of the radionuclide in question at the time of
measurement
-2
a) per unit of surface area Bq ∙ m
-1
b) per unit of mass Bq ∙ kg
c , c c Quantities to determine the decision threshold and limit of -
0 1, 2
detection
d Distance between the calibration source and the geometrical m
centre of the crystal
-1
Ambient dose rate as air kerma rate Gy ⋅ h
•
D
E Photon energy keV
E −αx -
∞
1
e
1. order exponential integral function E α = dx
() ∫
1
x
1
E −αx -
∞
2
e
2. order exponential integral function E ()α = dx
∫
2
2
1 x
f Decay factor -
d
f Factor for converting the activity of a radionuclide to ambient
D
dose rate as air kerma rate
2 -1 -1
a) per unit of surface area Gy ⋅ m ⋅ h ⋅ Bq
-1 -1
b) per unit of mass Gy ⋅ kg ⋅ h ⋅ Bq
Factor for converting the activity of a radionuclide to ambient
f
•
dose equivalent rate
H*(10)
2 -1 -1
a) per unit of surface area Sv ⋅ m ⋅ h ⋅ Bq
-1 -1
b) per unit of mass Sv ⋅ kg ⋅ h ⋅ Bq
G Geometry factor
a) per unit of surface area -
-2
b) per unit of mass kg ⋅ m
G(E, V) Geometry function of photon energy, E, and distribution, V
a) per unit of surface area -
-2
b) per unit of mass kg ⋅ m
-1
•
The dose equivalent rate at a point in a radiation field that Sv ⋅ h
*
would be produced by the corresponding expanded and aligned
H ()10
field in the ICRU sphere at a depth, d (here 10 mm), on the radius
opposing the direction of the aligned field
Quantiles of the standardized normal distribution -
kk, , kk,
11--αβ 12-γ /
k Angular coefficient for photon irradiation from the polar angu- -
m
lar segment, m
M Number of polar angular segments -
m Index for polar angular segment -
n Total counts of the total absorption line -
g
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ISO 18589-7:2013(E)
Table 1 (continued)
Symbols Designation Unit
n Background counts (under the region of the total absorption -
b
line)
n Net counts in the total absorption line -
n
p Emission probability per decay for the considered photon -
energy, E
R Radius of the distribution model m
R Radius of field of view m
s
u(x ) Standard uncertainty of the input quantity x The unit results from
i i
the input quantity.
2
Relative variance of the input quantity x The unit results from
i
ux
()
reli
the input quantity.
t Measuring time s
V Distribution model -
W Angular correction factor -
-2 -1
w Calibration factor to calculate the activity per unit of surface m or kg
area or mass of the radionuclide in question
w Calibration factor to calculate the radionuclide specific ambient -
h
dose equivalent rate
-2
ζ Mass per unit area kg ⋅ m
z Soil depth m
z′ Variable of integration of the soil depth -
ϑ Polar angle Degree
ε Detector efficiency
2
a) per unit of surface area m
b) per unit of mass kg
2
η Cross section of the detector for photons from the polar seg- m
m
ment, m
2
η Intrinsic efficiency m
0
External polar angle of the angular segment of interest Degree
ϑ
ext
Limit angle of the distribution model Degree
ϑ
lim
ϑ Internal polar angle of the angular segment of interest Degree
int
ϑ Aperture angle of the collimated spectrometer Degree
col
-1
μ Linear attenuation coefficient of air m
Air
2 -1
μ /ρ Mass attenuation coefficient of soil m ⋅ kg
S S
-3
ρ (z) Soil density as function of soil depth, z kg ⋅ m
S
-1 -2
Φ Density of flux of unscattered photons of energy E for distribu- s ⋅ m
tion model V at the detector location
Portion of flux density of unscattered photons of energy E -
Δ
Φ
m
resulting from polar angle segment m for distribution model V
Φ
EV,
at the detector location
-2
β Relaxation mass per unit area kg ⋅ m
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ISO 18589-7:2013(E)
4 Principles
4.1 Measurement method
In situ gamma spectrometry is a direct, physical method for fast determination of activity per unit of
surface area or per mass unit of gamma-emitting radionuclides present in or deposited on the soil surface.
In situ gamma spectrometry can be considered as a screening method that can supplement soil sampling
with a subsequent gamma spectrometry in the laboratory, with the following advantages:
— no time-consuming sampling and no test sample preparation necessary for laboratory;
— short measuring time;
— immediate availability of results in the field;
— representativeness of the results for a fairly large area corresponding to the field-of-view of the detector.
During the measurement, the detector is positioned preferably with the end cap down on an assembly jig.
For quantitative analysis of the pulse height spectra, assumptions are made concerning the distribution
of radionuclides in soil, as well as the specific physical properties of the soil and the air.
Genera
...
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