Water quality - Gross alpha activity - Test method using thick source (ISO 9696:2017)

ISO 9696:2017 specifies a method for the determination of gross alpha activity in non-saline waters for alpha-emitting radionuclides which are not volatile up to 350 °C.
The method is applicable to raw and potable waters.
The range of application depends on the amount of total soluble salts in the water and on the performance characteristics (background count rate and counting efficiency) of the counter.
It is the laboratory's responsibility to ensure the suitability of this method for the water samples tested.

Wasserbeschaffenheit - Gesamt-Alpha-Aktivität - Dickschichtverfahren (ISO 9696:2017)

Dieses Dokument legt ein Verfahren zur Bestimmung der Gesamt-Alpha-Aktivität von Alpha-Strahlen emittierenden Radionukliden in nicht-salzhaltigem Wasser fest, die bis zu 350 °C nicht flüchtig sind.
Das Verfahren ist auf Roh- und Trinkwasser anwendbar.
Der Arbeitsbereich hängt von der Menge an gelösten Salzen im Wasser und von der Leistungsfähigkeit (Nulleffektzählrate und Zählausbeute) der Zählvorrichtung ab.
Es liegt in der Verantwortung des Labors sicherzustellen, dass dieses Verfahren für die zu untersuchenden Wasserproben geeignet ist

Qualité de l'eau - Activité alpha globale - Méthode d'essai par source épaisse (ISO 9696:2017)

Le présent document spécifie une méthode de détermination de l'activité alpha globale dans les eaux non salines pour les radionucléides émetteurs alpha qui ne sont pas volatils jusqu'à 350 °C.
La méthode est applicable à l'analyse des eaux brutes et des eaux potables.
La gamme de validité de la méthode dépend de la quantité de sels solubles totaux contenus dans l'eau et des caractéristiques de performance (taux de comptage du bruit de fond et rendement de comptage) du compteur.
Il incombe au laboratoire de s'assurer que cette méthode est adaptée aux échantillons d'eau soumis à essai.

Kakovost vode - Skupna alfa aktivnost - Preskusna metoda robustnega vira (ISO 9696:2017)

Ta mednarodni standard določa metodo za določevanje skupne alfa aktivnosti v neslanih vodah za alfa oddajne radionuklide, ki niso hlapni pri 350 °C. Metoda omogoča določevanje podprtih hlapnih nukleotidov, ki se merijo do meje, določene na podlagi razpolovne dobe, ohranitve matrike (hlapnih nukleotidov) in trajanja meritve (čas štetja). Ta metoda se uporablja za neobdelano in pitno vodo. Območje uporabe je odvisno od količine lebdeče snovi v vodi in od lastnosti števca (stopnja štetja v ozadju in učinkovitost štetja).

General Information

Status
Published
Publication Date
14-Nov-2017
Technical Committee
Drafting Committee
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
15-Nov-2017
Completion Date
15-Nov-2017

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SLOVENSKI STANDARD
SIST EN ISO 9696:2018
01-januar-2018
1DGRPHãþD
SIST ISO 9696:2010
Kakovost vode - Skupna alfa aktivnost - Preskusna metoda robustnega vira (ISO
9696:2017)

Water quality - Gross alpha activity - Test method using thick source (ISO 9696:2017)

Wasserbeschaffenheit - Gesamt-Alpha-Aktivität - Dickschichtverfahren (ISO 9696:2017)

Qualité de l'eau - Activité alpha globale - Méthode d'essai par source concentrée (ISO

9696:2017)
Ta slovenski standard je istoveten z: EN ISO 9696:2017
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 9696:2018 en,fr,de

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

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SIST EN ISO 9696:2018
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SIST EN ISO 9696:2018
EN ISO 9696
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2017
EUROPÄISCHE NORM
ICS 13.060.60
English Version
Water quality - Gross alpha activity - Test method using
thick source (ISO 9696:2017)

Qualité de l'eau - Activité alpha globale - Méthode Wasserbeschaffenheit - Gesamt-Alpha-Aktivität -

d'essai par source concentrée (ISO 9696:2017) Dickschichtverfahren (ISO 9696:2017)

This European Standard was approved by CEN on 19 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: Avenue Marnix 17, B-1000 Brussels

© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9696:2017 E

worldwide for CEN national Members.
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SIST EN ISO 9696:2018
EN ISO 9696:2017 (E)
Contents Page

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

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SIST EN ISO 9696:2018
EN ISO 9696:2017 (E)
European foreword

This document (EN ISO 9696:2017) has been prepared by Technical Committee ISO/TC 147 "Water

quality" in collaboration with Technical Committee CEN/TC 230 “Water analysis” the secretariat of

which is held by DIN.

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 May 2018 and conflicting national standards shall be

withdrawn at the latest by May 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 9696:2017 has been approved by CEN as EN ISO 9696:2017 without any modification.

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SIST EN ISO 9696:2018
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SIST EN ISO 9696:2018
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9696
ISO/TC 147/SC 3
Water quality — Gross alpha activity
Secretariat: AFNOR
— Test method using thick source
Voting begins on:
2017­06­22
Qualité de l’eau — Activité alpha globale — Méthode d’essai par
source concentrée
Voting terminates on:
2017­08­17
ISO/CEN PARALLEL PROCESSING
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 9696:2017(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. ISO 2017
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, 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
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Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)
Contents Page

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

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols .......................................................................................................................................................................................................................... 2

5 Principle ........................................................................................................................................................................................................................ 2

6 Reagents and equipment ............................................................................................................................................................................. 3

6.1 Reagents........................................................................................................................................................................................................ 3

6.2 Equipment ................................................................................................................................................................................................... 4

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

7.1 Sampling ....................................................................................................................................................................................................... 5

7.2 Pretreatment ............................................................................................................................................................................................. 5

7.3 Concentration stage ............................................................................................................................................................................ 5

7.4 Sulfation stage ......................................................................................................................................................................................... 5

7.5 Ignition stage ............................................................................................................................................................................................ 6

7.6 Source preparation .............................................................................................................................................................................. 6

7.7 Measurement ............................................................................................................................................................................................ 6

7.8 Background determination .......................................................................................................................................................... 6

7.9 Preparation of the calibration source.................................................................................................................................. 6

7.10 Sensitivity and bias.............................................................................................................................................................................. 7

7.11 Optimization of the determination ........................................................................................................................................ 7

8 Contamination check ....................................................................................................................................................................................... 8

8.1 General ........................................................................................................................................................................................................... 8

8.2 Radon isotopes losses ....................................................................................................................................................................... 8

8.3 Polonium losses ......... ............................................................................................................................................................................. 8

9 Expression of results ........................................................................................................................................................................................ 8

9.1 Calculation of activity concentration ................................................................................................................................... 8

9.2 Standard uncertainty ......................................................................................................................................................................... 9

9.3 Decision threshold ............................................................................................................................................................................... 9

9.4 Detection limit ......................................................................................................................................................................................10

9.5 Confidence-interval limits ..........................................................................................................................................................10

10 Test report ................................................................................................................................................................................................................10

Annex A (informative) Performance criteria ............................................................................................................................................12

Bibliography .............................................................................................................................................................................................................................13

© ISO 2017 – All rights reserved iii
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(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 non­governmental, 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 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: w w w . i s o .org/ iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 147, Water quality, Subcommittee SC 3,

Radioactivity measurements.

This third edition cancels and replaces the second edition (ISO 9696:2007), which has been technically

revised.
iv © ISO 2017 – All rights reserved
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)
Introduction

Radioactivity from several naturally occurring and anthropogenic sources is present throughout

the environment. Thus, water bodies (e.g. surface waters, ground waters, sea waters) can contain

radionuclides of natural, human­made or of both origins:
40 3 14

— natural radionuclides, including K, H, C, and those originating from the thorium and uranium

226 228 234 238 210 210
decay series, in particular Ra, Ra, U, U, Po and Pb, can be found in water for

natural reasons (e.g. desorption from the soil and runoff by rain water) or can be released from

technological processes involving naturally occurring radioactive materials (e.g. the mining and

processing of mineral sands or phosphate fertilizers production and use);

— anthropogenic radionuclides, such as the transuranium elements (e.g. americium, plutonium,

3 14 90

neptunium and curium), H, C, Sr, and some gamma­emitting radionuclides can also be found in

natural waters. Small quantities of these radionuclides may be discharged from nuclear fuel cycle

facilities into the environment as the result of authorized routine releases. Some of these radionuclides

used for medical and industrial applications may also be released into the environment after use.

Anthropogenic radionuclides are also found in waters as the result of past fallout contamination

resulting from the above ground detonation of nuclear devices and accidents such as those that

occurred in Chernobyl and Fukushima.

Radionuclide activity concentration in water bodies can vary according to local geological

characteristics and climatic conditions and can be locally and temporally enhanced by releases from

[1]

nuclear installation during planned, existing and emergency exposure situations . Drinking water

may thus contain radionuclides at activity concentrations which could present a risk to human health.

The radionuclides present in liquid effluents are usually controlled before being discharged into

[2]

the environment and water bodies. Drinking water may be monitored for their radioactivity as

[3]

recommended by the World Health Organization (WHO) . Such control and monitoring can enable

to take proper actions to ensure that there is no adverse health effects to the public. Following these

international recommendations, radionuclide authorized concentration limits for liquid effluent

discharged to the environment and radionuclide guidance levels for water bodies and drinking water

are usually specified by national regulations for planned, existing and emergency exposure situations.

Compliance with these limits can be assessed using measurement results with their associated

uncertainties as requested by ISO/IEC Guide 98-3 and ISO 5667-20.

Depending on the exposure situation, the limits and guidance levels that would result in an action to

reduce health risk differ. As an example, during planned or existing situation, the WHO guidance for

screening levels in drinking water is 0,5 Bq/l for gross alpha activity and 1 Bq/l for gross beta activity.

NOTE The guidance level is the activity concentration with an intake of 2 l/d of drinking water for 1 year

that results in an effective dose of 0,1 mSv/a for members of the public, an effective dose that represents a very

[3]

low level of risk that is not expected to give rise to any detectable adverse health effect .

Thus, the test method may need to be adjusted depending if it is applied for either a planned-existing

or an emergency situation since during emergency situations, a large number of samples needs to

be rapidly characterized. The test methods could be adapted so that its performance in term of

characteristic limits, decision threshold and detection limit, and the uncertainties ensure that the

gross activity concentration test results permit the verification that they are below the guidance levels

[5][6][7].

required by national authority for either planned-existing situations or an emergency situation

Usually, the test methods can be adjusted to measure the gross activity concentration of the

radionuclide(s) in either wastewaters before storage or in liquid effluents before being discharged to

the environment. The test results will enable the plant/installation operator to comply with national

regulations in verifying that before their discharge, wastewaters/liquid effluent radioactive activity

concentrations are lower than the authorized limits.

The test method(s) described in this document may be used during planned, existing and emergency

exposure situations, as well as for wastewaters and liquid effluents with specific modifications that

could increase the overall uncertainty, detection limit and threshold.
© ISO 2017 – All rights reserved v
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)

The test method(s) may be used for water samples after proper sampling, sample handling and test

sample preparation (see the ad hoc part of ISO 5667).

An international standard on a test method of gross alpha and gross beta activity concentrations in

water samples is justified for test laboratories carrying out these measurements and may be required

by national authorities, as laboratories may have to obtain a specific accreditation for radionuclide

measurement of drinking water samples.

This document is one of a set of International Standards on test methods dealing with the measurement

of the activity concentration of radionuclides in water samples.
vi © ISO 2017 – All rights reserved
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SIST EN ISO 9696:2018
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 9696:2017(E)
Water quality — Gross alpha activity — Test method using
thick source

WARNING — Persons using this document should be familiar with normal laboratory practice.

This document does not purport to address all of the safety problems, if any, associated with its

use. It is the responsibility of the user to establish appropriate safety and health practices and to

ensure compliance with any national regulatory conditions.

IMPORTANT — It is absolutely essential that tests conducted in accordance with this document

be carried out by suitably trained staff.
1 Scope

This document specifies a method for the determination of gross alpha activity in non-saline waters for

alpha­emitting radionuclides which are not volatile up to 350 °C.
The method is applicable to raw and potable waters.

The range of application depends on the amount of total soluble salts in the water and on the

performance characteristics (background count rate and counting efficiency) of the counter.

It is the laboratory’s responsibility to ensure the suitability of this method for the water samples tested.

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.

ISO 3696:1987, Water for analytical laboratory use — Specification and test methods

ISO 5667­1, Water quality — Sampling — Part 1: Guidance on the design of sampling programmes and

sampling techniques

ISO 5667­3, Water quality — Sampling — Part 3: Preservation and handling of water samples

ISO 5667­14, Water quality — Sampling — Part 14: Guidance on quality assurance and quality control of

environmental water sampling and handling

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 80000­10, Quantities and units — Part 10: Atomic and nuclear physics

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

ISO/IEC Guide 98­3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in

measurement (GUM: 1995)

ISO/IEC Guide 99, International vocabulary of metrology — Basic and general concepts and associated

terms (VIM)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 11929, ISO 80000-10,

ISO/IEC Guide 98-3 and ISO/IEC Guide 99 apply.
© ISO 2017 – All rights reserved 1
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
4 Symbols
V volume of the water sample, in litres

V volume of test sample, in litres, equivalent to the mass of solid on the planchet

m mass, in milligrams, of ignited residue from volume, V
m mass of the sample residue deposited on the planchet, in milligrams
A alpha activity of the calibration source, in becquerels
c alpha activity concentration, in becquerels per litre
t background counting time, in seconds
t sample counting time, in seconds
r background count rate, per second
ts calibration count time of the alpha source, in seconds
r sample gross count rate, per second
r calibration count rate, per second
ε counting efficiency of the specified calibration source
S area of the planchet, in square millimetres

source thickness, in milligrams per square millimetres, of the sample residue deposited on

the planchet

standard uncertainty associated with the measurement result, in becquerels per litre

uc()

U expanded uncertainty calculated by U = k · u(a) with k = 1, 2.., in becquerels per litre

decision threshold, in becquerels per litre
detection limit, in becquerels per litre
cc, lower and upper limits of the confidence interval, in becquerels per litre
5 Principle

Gross alpha activity is determined by using a gas-flow proportional counter or a solid scintillation

counter [e.g. ZnS(Ag) detector] on water residue deposited on a planchet. The method requires a

uniform thickness and homogenous layer of residue deposit on the planchet as the sample positioning

in the detector could seriously influence the counting efficiency due to self-absorption of alpha particles

within the residue material.
2 © ISO 2017 – All rights reserved
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SIST EN ISO 9696:2018
ISO/FDIS 9696:2017(E)

Alpha activity shall be counted using either a silver-activated zinc sulfide scintillation screen, a silicon

charged-particle detector [ion-implanted silicon or surface barrier detector (SSB)] or a gas-flow

proportional counter (windowless or with a window of <100 μg · cm ).

Gross alpha measurement is not intended to give an absolute determination of total alpha activity in the

sample, but rather a screening analysis to ensure particular action levels of specific alpha emitters have

not been exceeded. This type of determination is also known as gross alpha index. Gross alpha analysis

is not expected to be as accurate nor as precise as specific radionuclide analysis after radiochemical

separations.

The sample is acidified for stabilization, evaporated to near dryness, converted to the sulfate form and

ignited at 350 °C. After transferring a portion of the residue to a planchet, the alpha activity is measured

in an alpha-particle detector or counting system previously calibrated against specific alpha-emitting

standards and the alpha activity concentration calculated. It should be noted that this method may

222

not allow the determination of some volatile species such as gaseous Rn and polonium halides. The

224

short­lived radionuclides (e.g. Ra) may also not be detected due to the time period between sampling

and analysis.
6 Reagents and equipment
6.1 Reagents

Except for the certified reference solution, all reagents shall be of recognized analytical grade and shall

not contain any measurable alpha activity.

A method for preparing reagent blanks to check for endemic radioactivity or contamination is given in

Clause 8.
6.1.1 Water, complying with ISO 3696:1987, grade 3.
6.1.2 Certified reference solution.

A calibration laboratory establishes traceability of its own measurement standards and measuring

instruments to the International System of Units (SI) by means of an unbroken chain of calibrations

or comparisons linking them to relevant primary standards of the SI units of measurement. The link

to SI units may be achieved by reference to national measurement standards. National measurement

standards may be primary standards, which are primary realizations of the SI units or agreed

representations of SI units based on fundamental physical constants, or they may be secondary

standards which are standards calibrated by another national metrology institute. When using external

calibration services, traceability of measurement shall be ensured by the use of calibration services

from laboratories that can demonstrate competence, measurement capability and traceability. The

calibration certificates issued by these laboratories shall contain the measurement results, including

the measurement uncertainty and/or a statement of compliance with an identified metrological

specification.

The choice of alpha standard depends on knowledge of the type of radioactive contaminant likely to be

present in the waters being tested. In general, this amounts to a choice between naturally occurring

and manmade alpha emitters.
241 239

Among standard solutions of artificial alpha-emitting radionuclides, Am and Pu are commonly

used. The presence of other impurities in the chosen alpha standard, which may emit alpha particles

241
or decay to
...

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