oSIST prEN 17216:2023
(Main)Construction products: Assessment of release of dangerous substances - Determination of radium-226, thorium-232 and potassium-40 activity using gamma-ray spectrometry
Construction products: Assessment of release of dangerous substances - Determination of radium-226, thorium-232 and potassium-40 activity using gamma-ray spectrometry
This document describes a test method for the determination of the activity of the radionuclides radium-226, thorium-232 and potassium-40 in construction products using semiconductor gamma-ray spectrometry.
This document describes sampling from a laboratory sample, sample preparation, and the sample measurement by semiconductor gamma-ray spectrometry. It includes background subtraction, energy and efficiency calibration, analysis of the spectrum, calculation of the activity concentrations with the associated uncertainties, the decision threshold and detection limit, and reporting of the results. The preparation of the laboratory sample from the initial product sample lies outside its scope and is described in product standards.
This document is intended to be non product-specific in scope, however, there are a limited number of product-specific elements such as the preparation of the laboratory sample and drying of the test portion. The method is applicable to samples from products consisting of single or multiple material components.
Bauprodukte - Bewertung der Freisetzung von gefährlichen Stoffen - Messung der spezifischen Aktivität von Radium-226, Thorium-232 und Kalium-40 mittels Halbleiter-Gammaspektrometrie
Dieses Dokument beschreibt ein Prüfverfahren zur Bestimmung der spezifischen Aktivitäten der Radionuklide Radium-226, Thorium-232 und Kalium-40 in Bauprodukten durch Halbleiter-Gammaspektrometrie.
Dieses Dokument beschreibt die Probenahme einer Laborprobe, die Probenvorbereitung und die Messung der Probe durch Halbleiter-Gammaspektrometrie. Dazu gehört die Hintergrundsubtraktion, Energie- und Effizienzkalibrierung, Spektralanalyse, Berechnung der Aktivität mit den zugehörigen Unsicherheiten oder der Berechnung der Erkennungsgrenze und Nachweisgrenze und Angabe der Prüfergebnisse.
Der Anwendungsbereich dieses Dokuments ist nicht produktspezifisch. Allerdings gibt es eine begrenzte Anzahl produktspezifischer Komponente, wie die Vorbereitung der Laborprobe und die Trocknung der Prüfmenge. Das Verfahren eignet sich für Produktproben, die aus einzelnen oder multiplen Bestandteilen bestehen.
Produits de construction: Évaluation de l’émission de substances dangereuses - Détermination de l’activité du radium 226, du thorium 232 et du potassium 40 dans les produits de construction par spectrométrie gamma
No Scope Available
Gradbeni proizvodi - Ocenjevanje sproščanja nevarnih snovi - Določanje aktivnosti radija Ra-226, torija Th-232 in kalija K-40 z gama spektrometrijo
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN 17216:2023
01-julij-2023
Gradbeni proizvodi - Ocenjevanje sproščanja nevarnih snovi - Določanje
aktivnosti radija Ra-226, torija Th-232 in kalija K-40 z gama spektrometrijo
Construction products: Assessment of release of dangerous substances - Determination
of radium-226, thorium-232 and potassium-40 activity using gamma-ray spectrometry
Bauprodukte - Bewertung der Freisetzung von gefährlichen Stoffen - Messung der
spezifischen Aktivität von Radium-226, Thorium-232 und Kalium-40 mittels Halbleiter-
Gammaspektrometrie
Ta slovenski standard je istoveten z: prEN 17216
ICS:
13.020.99 Drugi standardi v zvezi z Other standards related to
varstvom okolja environmental protection
17.240 Merjenje sevanja Radiation measurements
91.100.01 Gradbeni materiali na Construction materials in
splošno general
oSIST prEN 17216:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN 17216:2023
DRAFT
EUROPEAN STANDARD
prEN 17216
NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2023
ICS 91.100.01 Will supersede CEN/TS 17216:2018
English Version
Construction products: Assessment of release of
dangerous substances - Determination of radium-226,
thorium-232 and potassium-40 activity using gamma-ray
spectrometry
Bauprodukte - Bewertung der Freisetzung von
gefährlichen Stoffen - Messung der spezifischen
Aktivität von Radium-226, Thorium-232 und Kalium-
40 mittels Halbleiter-Gammaspektrometrie
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 351.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17216:2023 E
worldwide for CEN national Members.
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Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Symbols and abbreviations . 8
5 Principles of the test method . 11
6 Sampling and sample preparation . 11
6.1 Sampling scheme. 11
6.2 Sampling and sub-sampling . 12
6.3 Test specimen/test portion preparation . 13
7 Test procedure . 16
7.1 General. 16
7.2 Measurement . 16
8 Processing the test data . 19
8.1 General. 19
8.2 Analysis of the spectrum . 20
8.3 Calculating activity concentration . 20
8.4 Standard uncertainty. 22
8.5 Decision threshold . 24
8.6 Detection limit . 25
9 Test performance . 26
10 Test report . 27
Annex A (normative) Method for the determination of the radon leakage rate of a test specimen
container . 28
A.1 Principle . 28
A.2 Apparatus, equipment and reagents. 28
A.3 Test . 28
A.4 Processing experimental data . 29
Annex B (normative) Preparation of calibration sources and determination of detection
efficiency . 32
B.1 Principle . 32
B.2 Apparatus, equipment and reagents. 32
B.3 Standardized calibration sources . 32
B.4 Determination of the detection efficiency . 35
Annex C (normative) Method for the determination of the massic activity in a product
containing multiple constituents . 37
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Annex D (informative) Complementary photopeaks to verify the activity concentration in the
test specimen . 38
Annex E (informative) Method for the determination of the correct number of pulses in a
photopeak (only to be used for single peaks) . 39
Annex F (informative) Performance data . 40
Bibliography . 41
3
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European foreword
This document (prEN 17216:2023) has been prepared by Technical Committee CEN/TC 351
“Construction products: Assessment of release of dangerous substances”, the secretariat of which is held
by NEN.
The document is currently submitted to the CEN Enquiry.
The document will supersede CEN/TS 17216:2018.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
The main changes compared to the previous edition are as follows:
— Transfer of technical specification into European Standard;
— Addition of validation data from interlaboratory validation on repeatability and reproducibility (see
Clause 1, Clause 9 and Annex F); [to be completed for 2nd CEN Enquiry]
— Updating of normative and informative cross-references.
4
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Introduction
This document is a European Standard developed under Mandate M/366 issued by the European
Commission in the framework of the “Construction Products Directive” 89/106/EEC. This document
addresses the part of Mandate M/366 which provides for the preparation of horizontal
measurement/test methods for the determination of the activity of the radionuclides radium-226,
thorium-232 and potassium-40 in construction products using gamma-ray spectrometry.
Mandate M/366 is a complement to the product mandates issued by the European Commission to CEN
under the Construction Products Directive (CPD). The harmonized product standards (hEN) developed
in CEN under mandates (and ETAs developed in EOTA for products or kits) specify construction
product(s) as placed on the market and address their intended conditions of use.
The information produced by applying this document can be used for purposes of CE marking and
evaluation/attestation of conformity. Product specification, standardization of representative sampling
and procedures for any product-specific laboratory sample preparation are the responsibility of product
TCs and are not covered in this document.
This document supports existing regulations and standardized practices and is based on methods
described in standards such as EN ISO 10703, EN ISO 18589-2, EN ISO 18589-3 and NEN 5697. In
summary, this document describes the following:
— sampling, sub-sampling and test specimen preparation;
— measurement by gamma-ray spectrometry;
— background subtraction, energy and efficiency calibration, spectrum analysis;
— calculation of activities with associated uncertainties;
— reporting of results.
Determination of the activities is done by gamma-ray spectrometry. Procedures for all stages of the
analytical process are provided in this document. Although the tested sample rarely reflects a product’s
form under its intended conditions of use, the measured activity concentration is an intrinsic property of
the product. It does not vary with the construction product’s form. Consequently, the test results reflect
the radiological content of the product under its intended use. The document is intended to be non-
product-specific in scope. However, there are some limited elements related to the sample preparation
that are product-specific.
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1 Scope
This document describes a test method for the determination of the activity of the radionuclides radium-
226, thorium-232 and potassium-40 in construction products using semiconductor gamma-ray
spectrometry.
This document describes sampling from a laboratory sample, sample preparation, and the sample
measurement by semiconductor gamma-ray spectrometry. It includes background subtraction, energy
and efficiency calibration, spectrum analysis, activity calculation with the associated uncertainties or the
decision threshold and detection limit calculation, and the reporting of results.
The scope of this document is not product-specific. However, there are a limited number of product-
specific components, such as the preparation of the laboratory sample and drying of the test portion. The
method is applicable to samples from products consisting of single or multiple constituents.
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.
EN ISO 20042:2021, Measurement of radioactivity - Gamma-ray emitting radionuclides - Generic test
method using gamma-ray spectrometry (ISO 20042:2019)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
blank
test result obtained by carrying out the test procedure with an equivalent volume of demineralised or
distilled water instead of the test portion
1
, 3.3.4.1]
[SOURCE: EN 16687:2023
3.2
calibration source
sample with known radioactivity concentration and material properties that corresponds to the volume
and geometry of the test specimen
1
[SOURCE: EN 16687:2023 , 3.3.4.2]
3.3
crushed material
sample material prepared by crushing (a part) of the laboratory sample
1
[SOURCE: EN 16687:2023 , 3.3.4.4]
1
Under preparation. Stage at the time of publication: FprEN 16687:2023.
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3.4
dead time
time during spectrum acquisition (real time) during which pulses are not recorded or processed
Note 1 to entry: Dead time is given by real time minus live time.
Note 2 to entry: The time is given in seconds.
[SOURCE: EN ISO 20042:2021, 3.5]
3.5
laboratory sample
sample or sub-sample(s) sent to or received by the laboratory
1
[SOURCE: EN 16687:2023 , 3.2.2.1 – modified, Notes to entry removed]
3.6
live time
time during which pulses are processed during an acquisition (real) time
Note 1 to entry: The time is given in seconds.
Note 2 to entry: Live time is the counting time corrected for the dead time.
[SOURCE: EN ISO 20042:2021, 3.12]
3.7
test portion
amount of the test sample taken for testing/analysis purposes, usually of known dimension, mass or
volume
1
[SOURCE: EN 16687:2023 , 3.2.2.3 – modified, Examples removed]
3.8
test sample
sample, prepared from the laboratory sample, from which test portions are removed for testing or for
analysis
1
[SOURCE: EN 16687:2023 , 3.2.2.2]
Note 1 to entry: From the test sample a test portion is removed for determining the correction factor for dry mass,
and one or multiple test specimen(s) are removed for radiation testing.
3.9
test specimen
test portion specially prepared for testing in a test facility in order to determine the radiation behaviour
of the product under intended conditions of use
1
[SOURCE: EN 16687:2023 , 3.2.2.4 – modified to read ‘determine’ instead of ‘simulate’; Examples
removed]
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3.10
test specimen container
holder shaped like a beaker or a vessel that can be sealed and that is used to make determinations on the
test specimen
1
[SOURCE: EN 16687:2023 , 3.3.4.5]
4 Symbols and abbreviations
For the purposes of this document, the following symbols, names of quantities and units apply
Symbol Name of quantity Unit
A activity of the standardized calibration source j at energy E Bq
i;j i
a massic activity of radionuclide i Bq/kg
i
a massic activity of radionuclide i in the test specimen l Bq/kg
i;l
#
detection limit of radionuclide i of test specimen l Bq/kg
a
il;
*
decision threshold of radionuclide i of test specimen l Bq/kg
a
il;
E energy used for determining radionuclide i keV
i
f attenuation correction factor –
1
f true-summing correction factor –
2
f dead-time correction factor –
3
f decay correction factor –
4
f sample versus reference source positioning/height correction –
5
f is the mass fraction of the constituent j; –
j
i, j, l ordinals to indicate radionuclides, materials and samples –
k uncertainty coverage factor –
k uncertainty coverage factor with a default value of 1,65 at α = 0,05 –
1−α
k uncertainty coverage factor with a default value of 1,65 at β = 0,05 –
1−β
m dry mass of the test portion kg
d
3
m mass of the material constituent j per m of the construction product kg
j
m mass of matrix material j kg
j;mat
m mass of sub sample l of standardized material j kg
j;l;stand
m mass of the test specimen l kg
l
m fresh mass of the test portion kg
w
N corrected number of pulses in the photopeak –
N number of pulses collected in channel q –
q
average number of pulses per channel before the peak –
N
b
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Symbol Name of quantity Unit
average number of pulses per channel after the peak –
N
f
N net number of pulses in the photopeak that corresponds to energy E of –
i;j i
standardized calibration source j
N number of pulses that is collected in the continuum under the photopeak when –
cont;l
counting the test specimen l
N number of pulses that is collected in the continuum under the photopeak with –
cont;i;j;mat
energy E of matrix material j
i
N number of pulses that is collected in the continuum under the photopeak with –
cont;i;j;k;stand
energy E of sub sample k of standardized material j
i
N total number of pulses that is collected in the channels belonging to the –
tot;i;j;mat
photopeak with energy E of matrix material j
i
N total number of pulses that is collected in the channels belonging to the –
tot;i;j;k;stand
photopeak with energy E of sub sample k of standardized material j
i
N total number of pulses that is collected in the channels belonging to the –
tot;l
photopeak when counting the test specimen l
n number of test specimens –
P gamma-ray-emission probability at energy E –
i i
p , p , p free parameters used in an e-power formula –
1 2 3
−1
R counting rate of the blank that is determined from the number of pulses that is s
cont;0
collected in the continuum under the photopeak
−1
R counting rate of the test specimen l that is determined from the number of s
cont;l
pulses that is collected in the continuum under the photopeak
−1
R corrected counting rate of the blank s
cor;0
−1
R corrected specific counting rate of matrix material j at energy E (s·kg)
cor;i;j;spec;mat i
−1
R average specific corrected counting rate of all subsamples k of (s·kg)
cor;i;j;spec;stand
standardized material j at energy E
i
−1
R corrected specific counting rate of sub sample l of standardized material j at (s·kg)
cor;i;j;l;spec;stand
energy E
i
−1
R corrected counting rate of the test specimen l that is determined for the s
cor;l
photopeak
−1
R corrected counting rate in spectrum v of the tested container j s
cor;j;v
−1
R total counting rate of the blank that is determined from the total number of s
tot;0
pulses that is collected in the channels belonging to the photopeak
−1
R total counting rate of the test specimen l that is determined from the total s
tot;l
number of pulses that is collected in the channels belonging to the photopeak
S total radon production in the building material Bq/s
t live time s
t live time of the blank s
0
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Symbol Name of quantity Unit
t live time of the calibration source j s
j
t live time of matrix material j s
j;mat
t live time of sub sample l of standardized material j s
j;l;stand
t live time of the test specimen l s
l
t live time when measuring the radon leakage of the beaker s
L
t live time of the gas sample in spectrum w s
w
−1
up1 uncertainty in the free parameter p1 of the radon leakage test s
u external uncertainty of the mass activity of radionuclide i Bq/kg
i;ext
u internal uncertainty of the mass activity of radionuclide i Bq/kg
i;int
u uncertainty of the massic activity of radionuclide i from counting of the test Bq/kg
i;l;R
specimen l
u uncertainty of the massic activity of radionuclide i from counting of the test Bq/kg
i;R
specimen(s)
u total uncertainty of the massic activity of radionuclide i Bq/kg
i,tot
3
V sample volume m
v spectrum number, ascending from 1 to 10 –
w calibration factor for energy E for the conditions used in testing the test Bq∙s/kg
i;l i
specimen l
α probability of a first order error with a default value of 0,05 –
β probability of a second order error with a default value of 0,05 –
−1
εi;j radionuclide-specific counting efficiency for energy Ei and the standardized (Bq·s)
calibration source j
−1
ε radionuclide-specific counting efficiency for energy E and a counting (Bq·s)
i;l i
sample with mass m
l
η correction factor for dry mass of the test specimen –
−1
λL radon leakage rate (of the test specimen container) s
−1
λ decay constant of radon-222 s
Rn
−6 −1
NOTE λ = 2,1 × 10 s .
Rn
ν relative external uncertainty of the corrected specific counting rate of –
i;j;ext
standardized material j at energy E
i
νi;j;int relative internal uncertainty of the corrected specific counting rate of –
standardized material j at energy E
i
ν relative uncertainty due to radon-222 leakage from the test specimen –
L
container
ν relative uncertainty of the activity of radionuclide i associated with the term w –
i;w
ν relative uncertainty in the counting efficiency of radionuclide i –
i;ε
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5 Principles of the test method
The activity of the gamma-ray emitting radionuclides in construction products are determined using
gamma-ray spectrometry. Activity content is a material property independent from the physical form of
a construction product.
The activity of gamma-ray emitting radionuclides present in the test specimen is based on the analysis of
the energies and the peak areas obtained from the full-energy peaks of the gamma-ray lines in the
spectrum.
The test method requires accurate energy and efficiency calibration. Calibration methods presently used
in the laboratories can be applied, these shall be accompanied with a determination of the uncertainty.
Selected gamma-ray lines are specified to determine the relevant radionuclides.
The activity is determined by measuring a sample held in a container with a known geometry. This
determination, requiring as it does a test specimen of granular material, will only rarely reflect a
product's form under its intended conditions of use. Nevertheless, as the massic activity is an intrinsic
material property, it will reflect the massic activity under its intended conditions of use.
For radium-226 and thorium-232 the activity is determined using a progeny nuclide, while for potassium-
40 the activity is determined directly. In case the activity is determined using a progeny nuclide, a secular
equilibrium between the progeny nuclide and its originating nuclide shall be established. To reach
equilibrium between radium-226 and its progenies, the test specimen is stored in a radon-tight container
for a period of at least three weeks.
Despite the required waiting time of three weeks a disequilibrium in the thorium-232 decay chain can be
present. Such disequilibrium is caused by different dissolution ratios between thorium and radium, in
combination with its particular hydrogeological history or industrial processing. In case of such
disequilibrium the thorium-232 activity is approximated by the activity of radium-228 or thorium-228.
10
NOTE 1 Thorium-232 with a half-life of 1,41 × 10 years is the parent nuclide of the thorium decay chain.
Thorium-232 emits a 63,81 keV gamma ray with an emission probability of 0,263 %. It overlaps with the 63,28 keV
gamma ray emitted by thorium-234 with an emission probability of 4,1 %. Thus thorium-232 cannot be determined
directly by gamma-ray spectrometry. Determination through its progeny radionuclides actinium-228, lead-212 and
thallium-208 can be performed correctly only if these radionuclides are in radioactive equilibrium with thorium-
232.
NOTE 2 Where the activity of thorium-228 and radium-228 is significantly different, alternative measurement
techniques or procedures to determine the thorium-232 activity more accurately are available but are outside the
scope of this document.
6 Sampling and sample preparation
6.1 Sampling scheme
A flowchart of the sampling is presented in Figure 1 in support of the relevant definitions given in
Clause 3.
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Figure 1 — Diagram of the sample scheme
6.2 Sampling and sub-sampling
6.2.1 General
The method starts with a laboratory sample received by the laboratory. For the preparation of the
laboratory sample the following considerations should be taken into account:
a) For general guidance on sampling and sampling procedures for the making of a laboratory sample
reference should be made to CEN/TR 16220;
b) For construction products consisting of multiple constituents, a laboratory sample containing all of
the material constituents can be put forward for testing. Alternatively, each of the constituents can
be sent for testing individually. In that case the massic activity in the construction product shall be
calculated using the procedures described in Annex C (normative);
c) For construction products where blending of the various material constituents results in a change of
material composition or loss of weight, the calculation of the massic activity should consider the
composition of the construction product in its final state;
d) Where a cement-based concrete laboratory sample is prepared from a fresh, wet concrete, reference
should be made to the sampling procedures in EN 12350-1 and the production of hardened
specimens in EN 12390-2. These procedures are additional to the sampling procedures described in
CEN/TR 16220.
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A representative portion of the laboratory sample is crushed to make the test sample. For the materials
described in 6.3.2.1, no crushing is needed. From the test sample, test portions are taken for general
analytical testing and as a test specimen on which to perform radiation testing.
6.2.2 Sub-sampling from the laboratory sample
Randomly take some sub-samples from the laboratory sample. The random sub-samples shall contain
sufficient material to prepare a minimum of one test specimen and a test portion for general analytical
testing.
6.3 Test specimen/test portion preparation
6.3.1 Apparatus and ancillary materials
6.3.1.1 Crushing apparatus, used to obtain a test sample with particle sizes of no more than 2 mm,
such as for example a mortar or a ball mill.
6.3.1.2 Sieve, with apertures which retain particles of more than 2 mm.
6.3.1.3 Calibrated balance, with a measurement uncertainty not more than 0,1 % for the typical
mass of the test sample, test portion and test specimen.
6.3.1.4 M
...
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