CEN ISO/TR 22930-2:2021

Evaluating the performance of continuous air monitors - Part 2: Air monitors based on flow-through sampling techniques without accumulation (ISO/TR 22930-2:2020)

The use of a continuous air monitor (CAM) is mainly motivated by the need to be alerted quickly and in the most accurate way possible with an acceptable false alarm rate when significant activity concentration value is exceeded, in order to take appropriate measures to reduce exposure of those involved.
The performance of this CAM does not only depend on the metrological aspect characterized by the decision threshold, the limit of detection and the measurement uncertainties but also on its dynamic capacity characterized by its response time as well as on the minimum detectable activity concentration corresponding to an acceptable false alarm rate.
The ideal performance is to have a minimum detectable activity concentration as low as possible associated with a very short response time, but unfortunately these two criteria are in opposition. It is therefore important that the CAM and the choice of the adjustment parameters and the alarm levels be in line with the radiation protection objectives.
This document describes
—     the dynamic behaviour and the determination of the response time,
—     the determination of the characteristic limits (decision threshold, detection limit, limits of the coverage interval), and
—     a possible way to determine the minimum detectable activity concentration and the alarms setup.
Finally the annexes of this document show actual examples of CAM data which illustrate how to quantify the CAM performance by determining the response time, the characteristics limits, the minimum detectable activity concentration and the alarms setup.

Ermittlung der Leistungsfähigkeit kontinuierlicher Luftmonitore - Teil 2: Luftmonitore basierend auf Durchfluss-Sammeltechnik ohne Anreicherung (ISO/TR 22930-2:2020)

Die Verwendung eines kontinuierlichen Luftmonitors (CAM, en: continuous air monitor) ist hauptsächlich darin begründet, bei der Überschreitung eines signifikanten Werts der Aktivitätskonzentration schnell und mit einer akzeptablen Fehlalarmrate möglichst genau alarmiert zu werden, um geeignete Maßnahmen zu ergreifen, um die Exposition der Beteiligten zu verringern.
Die Leistungsfähigkeit dieser kontinuierlichen Luftmonitore hängt nicht nur vom metrologischen Aspekt, der durch die Erkennungsgrenze, die Nachweisgrenze und die Messunsicherheiten charakterisiert ist, ab, son¬dern auch von der dynamischen Kapazität, die durch die Ansprechzeit charakterisiert ist, sowie von der kleinsten nachweisbaren Aktivitätskonzentration, die einer akzeptablen Fehlalarmrate entspricht.
Eine ideale Leistungsfähigkeit wäre eine möglichst geringe nachweisbare Aktivitätskonzentration, die mit einer sehr kurzen Ansprechzeit verbunden ist, jedoch stehen diese beiden Kriterien zueinander im Wider-spruch. Es ist daher wichtig, die kontinuierlichen Luftmonitore und die Wahl der Einstellparameter und Alarm¬schwellen in Einklang mit den Strahlenschutzzielen zu bringen.
Dieses Dokument beschreibt:
–   das dynamische Verhalten und die Ermittlung der Ansprechzeit,
–   die Bestimmung der charakteristischen Grenzen (Erkennungsgrenze, Nachweisgrenze, Grenzen des Überdeckungsintervalls) und
–   einen möglichen Weg, die kleinste nachweisbare Aktivitätskonzentration und die Alarmeinstellungen zu bestimmen.
Abschließend zeigen die Anhänge dieses Dokuments aktuelle Beispiele von CAM-Daten, die aufzeigen, wie die Leistungsfähigkeit eines kontinuierlichen Luftmonitors anhand der Bestimmung der Ansprechzeit, der cha¬rakteristischen Grenzen, der kleinsten nachweisbaren Aktivitätskonzentration und der Alarmeinstellungen quantifiziert werden kann.

Évaluation des performances des dispositifs de surveillance de l'air en continu - Partie 2: Dispositifs de surveillance de l’air basés sur des techniques d’échantillonnage par circulation sans accumulation (ISO/TR 22930-2:2020)

L'utilisation d'un dispositif de surveillance de l'air en continu (CAM) est principalement motivée par la nécessité d'être alerté rapidement et de la façon la plus précise possible avec un taux acceptable de fausses alarmes lorsqu'une valeur d'activité volumique significative est dépassée, afin de prendre des mesures appropriées pour réduire l'exposition des personnes concernées.
Les performances de ce CAM dépendent non seulement de l'aspect métrologique caractérisé par le seuil de décision, la limite de détection et les incertitudes de mesure, mais aussi de sa capacité dynamique caractérisée par son temps de réponse ainsi que de l'activité volumique minimale détectable correspondant à un taux de fausses alarmes acceptable.
La situation idéale serait d'avoir une activité volumique minimale détectable aussi faible que possible et un temps de réponse associé très court, mais ces deux critères sont malheureusement en opposition. Il est donc important que le CAM et le choix des paramètres de réglage et des niveaux d'alarme soient alignés sur les objectifs de la radioprotection.
Le présent document décrit
—          le comportement dynamique et la détermination du temps de réponse,
—          la détermination des limites caractéristiques (seuil de décision, limite de détection, limites de l'intervalle élargi), et
—          une méthode possible pour déterminer l'activité volumique minimale détectable et le paramétrage des alarmes.
Les annexes du présent document présentent ensuite des exemples actuels de données de CAM qui illustrent la quantification des performances d'un CAM en déterminant le temps de réponse, les limites caractéristiques, l'activité volumique minimale détectable et le paramétrage des alarmes.

Ugotavljanje zmogljivosti neprekinjeno delujočih zračnih nadzornikov - 2. del: Zračni nadzorniki na podlagi tehnik vzorčenja pretoka zraka brez kopičenja (ISO/TR 22930-2:2020)

General Information

• Status: Published
• Publication Date: 24-Aug-2021
• ICS: 13.280 - Radiation protection
• 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: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 25-Aug-2021
• Due Date: 16-Sep-2022
• Completion Date: 25-Aug-2021
• Ref Project: SIST-TP CEN ISO/TR 22930-2:2021 - Evaluating the performance of continuous air monitors - Part 2: Air monitors based on flow-through sampling techniques without accumulation (ISO/TR 22930-2:2020)

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2021
Ugotavljanje zmogljivosti neprekinjeno delujočih zračnih nadzornikov - 2. del:
Zračni nadzorniki na podlagi tehnik vzorčenja pretoka zraka brez kopičenja
(ISO/TR 22930-2:2020)
Evaluating the performance of continuous air monitors - Part 2: Air monitors based on
flow-through sampling techniques without accumulation (ISO/TR 22930-2:2020)
Ermittlung der Leistungsfähigkeit kontinuierlicher Luftmonitore - Teil 2: Luftmonitore
basierend auf Durchfluss-Sammeltechnik ohne Anreicherung (ISO/TR 22930-2:2020)
Évaluation des performances des dispositifs de surveillance de l'air en continu - Partie 2:
Dispositifs de surveillance de l’air basés sur des techniques d’échantillonnage par
circulation sans accumulation (ISO/TR 22930-2:2020)
Ta slovenski standard je istoveten z: CEN ISO/TR 22930-2:2021
ICS:
13.280 Varstvo pred sevanjem Radiation protection
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

CEN ISO/TR 22930-2
TECHNICAL REPORT
RAPPORT TECHNIQUE
August 2021
TECHNISCHER BERICHT
ICS 13.280
English Version
Evaluating the performance of continuous air monitors -
Part 2: Air monitors based on flow-through sampling
techniques without accumulation (ISO/TR 22930-2:2020)
Évaluation des performances des dispositifs de Ermittlung der Leistungsfähigkeit kontinuierlicher
surveillance de l'air en continu - Partie 2: Dispositifs de Luftmonitore - Teil 2: Luftmonitore basierend auf
surveillance de l'air basés sur des techniques Durchfluss-Sammeltechnik ohne Anreicherung
d'échantillonnage par circulation sans accumulation (ISO/TR 22930-2:2020)
(ISO/TR 22930-2:2020)
This Technical Report was approved by CEN on 16 August 2021. It has been drawn up by the Technical Committee CEN/TC 430.

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, 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TR 22930-2:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
The text of ISO/TR 22930-2:2020 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 CEN ISO/TR 22930-2:2021 by Technical Committee
CEN/TC 430 “Nuclear energy, nuclear technologies, and radiological protection” the secretariat of
which is held by AFNOR.
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.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
Endorsement notice
The text of ISO/TR 22930-2:2020 has been approved by CEN as CEN ISO/TR 22930-2:2021 without any
modification.
TECHNICAL ISO/TR
REPORT 22930-2
First edition
2020-05
Evaluating the performance of
continuous air monitors —
Part 2:
Air monitors based on flow-through
sampling techniques without
accumulation
Évaluation de la performance des dispositifs de surveillance de l'air
en continu —
Partie 2: Moniteurs d'air basés sur des techniques d'échantillonnage
par circulation sans accumulation
Reference number
ISO/TR 22930-2:2020(E)
©
ISO 2020
ISO/TR 22930-2:2020(E)
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
ii © ISO 2020 – All rights reserved

ISO/TR 22930-2:2020(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols . 4
5 Measuring principle . 6
6 Study of dynamic behaviour . 7
7 Evaluation of the characteristic limits .13
7.1 General .13
7.2 Single detector .13
7.2.1 General.13
7.2.2 Definition of the model .14
7.2.3 Standard uncertainty .14
7.2.4 Decision threshold.15
7.2.5 Detection limit .17
7.2.6 Limits of the coverage interval .17
7.3 Double detector .17
7.3.1 General.17
7.3.2 Definition of the model .18
7.3.3 Standard uncertainty .18
7.3.4 Decision threshold.19
7.3.5 Detection limit .20
7.3.6 Limits of the coverage interval .20
8 Alarms setup, minimum detectable concentration and potential missed exposure .20
Annex A (informative) Application example: Single detector with a proportional counter .23
Annex B (informative) Application example: Double detector in current mode .26
Bibliography .32
ISO/TR 22930-2:2020(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
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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
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 voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 85, Nuclear energy, nuclear technologies,
and radiological protection, Subcommittee SC 2, Radiological protection.
A list of all the parts in the ISO/TR 22930 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved

ISO/TR 22930-2:2020(E)
Introduction
Sampling and monitoring of airborne activity concentration in workplaces are critically important for
maintaining worker safety at facilities where dispersible radioactive substances are used.
The first indication of a radioactive substance dispersion event comes, in general, from a continuous
air monitor (CAM) and its associated alarm levels. In general, the response of a CAM is delayed in time
compared to the actual situation of release.
The knowledge of a few factors is needed to interpret the response of a CAM and to select the appropriate
CAM type and its operating parameters.
The role of the radiation protection officer is to select the appropriate CAM, to determine when effective
release of radioactive substances occurs, to interpret measurement results and to take corrective
action appropriate to the severity of the release.
The objective of ISO/TR 22930 series is to assist radiation protection officer in evaluating the
performance of a CAM.
ISO/TR 22930 series describes the factors and operating parameters and how they influence the
response of a CAM.
This document deals with monitoring systems based on flow-through sampling techniques without
accumulation.
SIST-TP
...