EN ISO 20045:2024

Measurement of the radioactivity in the environment - Air: tritium - Test method using bubbler sampling (ISO 20045:2023, including corrected version 2023-09)

This document describes a test method to determine the activity concentration of atmospheric tritium by trapping tritium in air by bubbling through a water solution.
The formulae are given for a sampling system with four bubblers. They can also be applied to trapping systems with only one trapping module consisting of two bubblers if only tritiated water vapour (HTO) is in the atmosphere to be sampled.
This document does not cover laboratory test sample results, in becquerel per litre of trapping solution, according to ISO 9698 or ISO 13168.
The test method detection limit result is between 0,2 Bq∙m-3 and 0,5 Bq∙m-3 when the sampling duration is about one week.

Bestimmung der Radioaktivität in der Umwelt - Luft: Tritium - Messverfahren mit Sammlung mittels Gaswaschflaschen (ISO 20045:2023, einschließlich der korrigierten Fassung von 2023-09)

Dieses Dokument beschreibt ein Prüfverfahren zur Bestimmung der Aktivitätskonzentration luftgetragenen Tri¬tiums durch Einfangen des Tritiums in einer in Gaswaschflaschen enthaltenen wässrigen Lösung. Akti-vitäts¬konzentrationen luftgetragenen Tritiums werden in Becquerel je Kubikmeter (Bqm–3) angegeben.
Die Gleichungen sind für ein Probenahmesystem mit vier Gaswaschflaschen angegeben. Sie können auch für Sammler mit nur einer Sammeleinheit aus zwei Gaswaschflaschen angewendet werden, wenn nur tritiierter Wasserdampf (HTO) aus der Luft gesammelt werden soll.
Dieses Dokument behandelt nicht Ergebnisse von Laborproben in Becquerel je Liter der Rückhaltelösung nach ISO 9698 oder ISO 13168.
Die Nachweisgrenze des Prüfverfahrens liegt zwischen 0,2 Bqm–3 und 0,5 Bqm–3 bei einer Probenahme-dauer von etwa 1 Woche.

Mesurage de la radioactivité dans l’environnement - Air : tritium - Méthode d’essai à l’aide d’un prélèvement par barbotage (ISO 20045:2023, y compris version corrigée 2023-09)

Merjenje radioaktivnosti v okolju - Zrak: tritij - Preskusna metoda z vzorčenjem z mehurčki (ISO 20045:2023)

General Information

• Status: Not Published
• Publication Date: 16-Jul-2024
• ICS: 13.040.01 - Air quality in general
• ICS: 17.240 - Radiation measurements
• Technical Committee: CEN/TC 430 - Nuclear energy, nuclear technologies, and radiological protection
• Drafting Committee: CEN/TC 430 - Nuclear energy, nuclear technologies, and radiological protection
• Current Stage: 6055 - CEN Ratification completed (DOR) - Publishing
• Start Date: 07-Jul-2024
• Due Date: 18-Feb-2026
• Completion Date: 07-Jul-2024
• Ref Project: oSIST prEN ISO 20045:2024 - Measurement of the radioactivity in the environment - Air: tritium - Test method using bubbler sampling (ISO 20045:2023)

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2024
Merjenje radioaktivnosti v okolju - Zrak: tritij - Preskusna metoda z vzorčenjem z
mehurčki (ISO 20045:2023)
Measurement of the radioactivity in the environment - Air: tritium - Test method using
bubbler sampling (ISO 20045:2023)
Mesurage de la radioactivité dans l’environnement - Air : tritium - Méthode d’essai à
l’aide d’un prélèvement par barbotage (ISO 20045:2023)
Ta slovenski standard je istoveten z: prEN ISO 20045
ICS:
13.040.01 Kakovost zraka na splošno Air quality in general
17.240 Merjenje sevanja Radiation measurements
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL ISO
STANDARD 20045
First edition
2023-05
Measurement of the radioactivity in
the environment — Air: tritium — Test
method using bubbler sampling
Mesurage de la radioactivité dans l’environnement — Air : tritium —
Méthode d’essai à l’aide d’un prélèvement par barbotage
Reference number
ISO 20045:2023(E)
ISO 20045:2023(E)
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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or ISO’s member body in the country of the requester.
ISO copyright office
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Published in Switzerland
ii
ISO 20045:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and symbols . 1
3.1 Terms and definitions . 2
3.2 Symbols, definitions and units . 3
4 Principle . 4
5 Influence quantities . 6
6 Equipment . 6
6.1 Description and requirements of the sampling system . 6
6.2 Location of sampling head . 7
6.3 Air flow rate, sampling duration and air volume sampling . 7
6.4 Trapping water solution . 7
6.5 Specifications for use . 7
7 Procedure .8
7.1 Sampling . 8
7.2 Sample collection and transportation . 9
7.3 Receipt. 9
7.4 Conservation . 9
7.5 Tritium activity concentration measurement . 9
8 Expression of results . 9
8.1 General . 9
8.2 Calculations for tritiated water vapour . 10
8.2.1 Activity concentration . . 10
8.2.2 Decision threshold . 10
8.2.3 Detection limit . 11
8.2.4 Coverage intervals limits . 11
8.2.5 Conditions of use .12
8.3 Calculation for tritiated gas compounds .12
8.3.1 Tritiated gas without significant HTO level .13
8.3.2 Tritiated gas compounds with significant HTO level . 14
8.3.3 Coverage intervals limits . 16
8.3.4 Conditions of use . 16
9 Test report .17
Annex A (informative) Technical data for tritium .19
Annex B (informative) Determination of trapping efficiency .21
Annex C (informative) Preserving of tritiated water solutions .25
Annex D (informative) Example of sampling and calculations forms .26
Annex E (informative) Examples of calculations of air tritium activity concentrations .29
Bibliography .35
iii
ISO 20045:2023(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
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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
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URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies,
and radiological protection, SC 2, Radiological protection.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
ISO 20045:2023(E)
Introduction
Everyone is exposed to natural radiation. The natural sources of radiation include cosmic rays and
naturally occurring radioactive substances which exist on Earth such as flora, fauna or the human body.
Human activities involving the use of radiation and radioactive substances add to the radiation exposure
from this natural exposure. Some of those activities, such as the mining and use of ores containing
naturally-occurring radioactive materials (NORM) and the production of energy by burning coal that
contains such substances, simply enhance the exposure from natural radiation sources. Nuclear power
plants and other nuclear installations use radioactive materials and produce radioactive effluents and
waste during operation and decommissioning. The use of radioactive materials in industry, medicine,
agriculture and research is expanding around the globe.
All these human activities give rise to radiation exposures that are only a small fraction of the global
average level of natural exposure. The medical use of radiation is the largest and a growing man-made
source of radiation exposure in developed countries. It includes diagnostic radiology, radiotherapy,
nuclear medicine and interventional radiology.
Radiation exposure also occurs as a result of occupational activities. It is incurred by workers in
industry, medicine and research using radiation or radioactive substances, as well as by passengers
and crew during air travel. The average level of occupational exposures is generally below the global
average level of natural radiation exposure (see Reference [2]).
As uses of radiation increase, so do the potential health risk and the public's concerns. Thus, all these
exposures are regularly assessed in order to
a) improve the understanding of global levels and temporal trends of public and worker exposure,
b) evaluate the components of exposure so as to provide a measure of their relative impact, and
c) identify emerging issues that may warrant more attention and study. While doses to workers
are mostly directly measured, doses to the public are usually assessed by indirect methods
using the results of radioactivity measurements of waste, liquid and/or gaseous effluents and/or
environmental samples.
Radioactivity from several naturally-occurring and anthropogenic sources is present throughout the
environment. Thus, atmosphere can contain radionuclides of natural, human-made, or both origins.
40 3 14
— Natural radionuclides including K, H, C and those originating from the thorium and uranium
226 228 234 238 210
decay series, in particular
...