Water quality - Gross beta activity in non-saline water - Test method using thick source (ISO 9697:2015)

This International Standard specifies a method for the determination of gross beta activity in non-saline waters. The method covers non-volatile beta emitter radionuclides with beta-max energies > 0,3 MeV. Measurement of very low energy beta−emitters like 3H; 14C, 35S and 241Pu is not included in this standard. The method is applicable to the analysis of raw and potable waters.

Wasserbeschaffenheit - Bestimmung der Gesamt-Beta-Aktivität in nicht-salzhaltigem Wasser - Dickschichtverfahren (ISO 9697:2015)

Qualité de l'eau - Activité bêta globale des eaux non salines - Méthode d'essai par source concentrée (ISO 9697:2015)

L'ISO 9697:2015 spécifie une méthode d'essai permettant de déterminer l'activité volumique bêta globale des eaux non salines. La méthode couvre les radionucléides non volatils émetteurs bêta avec des énergies maximales d'environ 0,3 MeV ou plus élevées. Les mesurages des émetteurs bêta à faible énergie (par exemple, 3H, 228Ra, 210Pb, 14C, 35S et 241Pu) et de certains radionucléides gazeux ou volatils (par exemple, radon et iode radioactif) peuvent ne pas être inclus dans la quantification bêta globale en utilisant la méthode d'essai décrite dans l'ISO 9697:2015.
Cette méthode d'essai est applicable à l'analyse des eaux brutes et potables. La gamme d'application dépend de la quantité de sels solubles totaux dans l'eau et des caractéristiques de performance (taux de comptage du bruit de fond et efficacité de comptage) du compteur utilisé. Il incombe au laboratoire de s'assurer de l'adéquation de cette méthode pour les échantillons d'eau soumis à essai.

Kakovost vode - Skupna beta aktivnost v neslanih vodah - Preskusna metoda robustnega vira (ISO 9697:2015)

Ta mednarodni standard opisuje metodo za določevanje skupne beta aktivnosti v neslanih vodah. Metoda zajema nehlapne beta oddajne radionuklide z maks. beta energijo > 0,3 MeV. Ta standard ne vključuje merjenja beta oddajnikov z zelo nizko energijo, npr.3H, 14C, 35S in 241Pu. Ta metoda se uporablja za analizo neobdelane in pitne vode.

General Information

Status
Withdrawn
Public Enquiry End Date
01-Feb-2016
Publication Date
07-Nov-2017
Withdrawal Date
06-Aug-2019
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
01-Aug-2019
Due Date
24-Aug-2019
Completion Date
07-Aug-2019

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SLOVENSKI STANDARD
SIST EN ISO 9697:2017
01-december-2017
Kakovost vode - Skupna beta aktivnost v neslanih vodah - Preskusna metoda
robustnega vira (ISO 9697:2015)

Water quality - Gross beta activity in non-saline water - Test method using thick source

(ISO 9697:2015)

Wasserbeschaffenheit - Bestimmung der Gesamt-Beta-Aktivität in nicht-salzhaltigem

Wasser - Dickschichtverfahren (ISO 9697:2015)

Qualité de l'eau - Activité bêta globale des eaux non salines - Méthode d'essai par

source concentrée (ISO 9697:2015)
Ta slovenski standard je istoveten z: EN ISO 9697:2017
ICS:
13.060.60 Preiskava fizikalnih lastnosti Examination of physical
vode properties of water
17.240 Merjenje sevanja Radiation measurements
SIST EN ISO 9697:2017 en,fr,de

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

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SIST EN ISO 9697:2017
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SIST EN ISO 9697:2017
EN ISO 9697
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2017
EUROPÄISCHE NORM
ICS 13.280; 13.060.60
English Version
Water quality - Gross beta activity in non-saline water -
Test method using thick source (ISO 9697:2015)

Qualité de l'eau - Activité bêta globale des eaux non Wasserbeschaffenheit - Bestimmung der Gesamt-Beta-

salines - Méthode d'essai par source concentrée (ISO Aktivität in nicht-salzhaltigem Wasser -

9697:2015) Dickschichtverfahren (ISO 9697:2015)
This European Standard was approved by CEN on 27 May 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, 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 9697:2017 E

worldwide for CEN national Members.
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SIST EN ISO 9697:2017
EN ISO 9697:2017 (E)
Contents Page

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

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SIST EN ISO 9697:2017
EN ISO 9697:2017 (E)
European foreword

The text of ISO 9697:2015 has been prepared by Technical Committee ISO/TC 147 “Water quality” of

the International Organization for Standardization (ISO) and has been taken over as EN ISO 9697:2017

by 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 December 2017, and conflicting national standards

shall be withdrawn at the latest by December 2017.

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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
Endorsement notice

The text of ISO 9697:2015 has been approved by CEN as EN ISO 9697:2017 without any modification.

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SIST EN ISO 9697:2017
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SIST EN ISO 9697:2017
INTERNATIONAL ISO
STANDARD 9697
Third edition
2015-04-01
Water quality — Gross beta activity
in non-saline water — Test method
using thick source
Qualité de l’eau — Activité bêta globale des eaux non salines —
Méthode d’essai par source concentrée
Reference number
ISO 9697:2015(E)
ISO 2015
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SIST EN ISO 9697:2017
ISO 9697:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015

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
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2015 – All rights reserved
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SIST EN ISO 9697:2017
ISO 9697:2015(E)
Contents Page

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

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

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

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

3 Symbols, definitions, and units ............................................................................................................................................................. 2

4 Principle ........................................................................................................................................................................................................................ 3

5 Reagents and equipment ............................................................................................................................................................................. 3

5.1 Reagents........................................................................................................................................................................................................ 3

5.2 Equipment ................................................................................................................................................................................................... 3

6 Procedure..................................................................................................................................................................................................................... 4

6.1 Sampling ....................................................................................................................................................................................................... 4

6.2 Pretreatment ............................................................................................................................................................................................. 4

6.3 Concentration stage ............................................................................................................................................................................ 4

6.4 Sulfation stage ......................................................................................................................................................................................... 5

6.5 Ignition stage ............................................................................................................................................................................................ 5

6.6 Source preparation .............................................................................................................................................................................. 5

6.7 Measurement ............................................................................................................................................................................................ 5

6.8 Determination of counting background ............................................................................................................................ 6

6.9 Preparation of calibration sources ........................................................................................................................................ 6

6.10 Sensitivity and bias.............................................................................................................................................................................. 6

6.11 Optimization of the determination ........................................................................................................................................ 6

7 Source control ......................................................................................................................................................................................................... 7

7.1 Contamination check ......................................................................................................................................................................... 7

7.2 Potential disequilibrilium of radionuclides ................................................................................................................... 7

8 Expression of results ........................................................................................................................................................................................ 7

8.1 Calculation of activity concentration ................................................................................................................................... 7

8.2 Standard uncertainty ......................................................................................................................................................................... 8

8.3 Decision threshold ............................................................................................................................................................................... 9

8.4 Detection limit ......................................................................................................................................................................................... 9

8.5 Confidence limits................................................................................................................................................................................... 9

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

Annex A (informative) Example of performance criteria ............................................................................................................11

Bibliography .............................................................................................................................................................................................................................12

© ISO 2015 – All rights reserved iii
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SIST EN ISO 9697:2017
ISO 9697:2015(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 (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 meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers

to Trade (TBT), see the following URL: Foreword — Supplementary information.

The committee responsible for this document is ISO/TC 147, Water quality, Subcommittee SC 3,

Radioactivity measurements.

This third edition cancels and replaces the second edition (ISO 9697:2008), which has been

technically revised.
iv © ISO 2015 – All rights reserved
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SIST EN ISO 9697:2017
ISO 9697:2015(E)
Introduction

Radioactivity from several naturally occurring and anthropogenic sources is present throughout the

environment. Thus, water bodies (e.g. surface water, groundwater, seawater) can contain the following

radionuclides of natural or human-made origins:

— natural radionuclides, including potassium-40 and those originating from the thorium and uranium

decay series, particularly radium-226, radium-228, uranium-234, uranium-238, and lead-210, can

be found in water for natural reasons (e.g. desorption from the soil and wash-off 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 the production and use of phosphate fertilizer);

— human-made radionuclides, such as transuranium elements (americium, plutonium, neptunium,

curium), tritium, carbon-14, strontium-90, and some gamma-emitting radionuclides, can also be found

in natural waters as a result of authorized routine releases into the environment in small quantities of

the effluent discharged from nuclear fuel cycle facilities. They are also released into the environment

following their use in unsealed form for medical and industrial applications. They are also found in

the water as a result of past fallout contamination resulting from the explosion in the atmosphere of

nuclear devices and accidents such as those that occurred in Chernobyl and Fukushima.

Drinking water can thus contain radionuclides at activity concentrations which could present a risk to

human health. In order to assess the quality of drinking water (including mineral waters and spring

waters), with respect to its radionuclide content and to provide guidance on reducing health risks by

taking measures to decrease radionuclide activity concentrations, water resources (groundwater, river,

lake, sea, etc.) and drinking water are monitored for their radioactivity content as recommended by the

World Health Organization (WHO) and can be required by some national authorities.

An International Standard on a test method for gross beta activity in water samples is justified for

test laboratories carrying out these measurements, required sometimes by national authorities, as

laboratories might have to obtain a specific accreditation for radionuclide measurement in drinking

water samples.
−1 [1]

The screening level for gross beta activity in drinking water, as recommended by WHO, is 1 Bq l . If this

value is not exceeded, an effective dose of 0,1 mSv year should not be exceeded. In case that gross beta

screening level is exceeded, it is recommended that the specific radionuclides should be identified and

their individual activity concentrations measured. Gross beta measurements based on the evaporation

method include a contribution from potassium-40, a naturally occurring beta emitter in a fixed ratio to

stable potassium. If the screening level of 1 Bq l for gross beta is exceeded, a separate determination

of total potassium in water should be performed to subtract the contribution of potassium-40 to beta

activity. The factor of 27,6 Bq g of beta activity to total potassium should be used to calculate the

[1]
potassium-40 contribution.

NOTE The screening level is determined based on the activity concentration with an intake of 2 l day of

drinking water for 1 year that results in an effective dose of less than 0,1 mSv year for members of the public,

an effective dose that represents a very low level of risk that is not expected to give rise to any detectable adverse

health effect.

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

measurement of gross activity of radionuclides in water samples. Other related standards include

— ISO 9696,
— ISO 10704, and
— ISO 11704.
© ISO 2015 – All rights reserved v
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SIST EN ISO 9697:2017
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SIST EN ISO 9697:2017
INTERNATIONAL STANDARD ISO 9697:2015(E)
Water quality — Gross beta activity in non-saline water —
Test method using thick source

WARNING — Persons using this International Standard should be familiar with normal laboratory

practice. This International Standard does not purport to address all of the safety issues, 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 according to this International

Standard be carried out by suitably trained staff.
1 Scope

This International Standard specifies a test method for the determination of gross beta activity

concentration in non-saline waters. The method covers non-volatile radionuclides with maximum beta

3 228

energies of approximately 0,3 MeV or higher. Measurement of low energy beta emitters (e.g. H, Ra,

210 14 35 241

Pb, C, S, and Pu) and some gaseous or volatile radionuclides (e.g. radon and radioiodine) might not

be included in the gross beta quantification using the test method described in this International Standard.

This test method is applicable to the analysis of raw and drinking 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 used.

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

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

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

sampling techniques

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

ISO 5667-14, 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 80000-10, 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 98-3, 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)
© ISO 2015 – All rights reserved 1
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SIST EN ISO 9697:2017
ISO 9697:2015(E)
3 Symbols, definitions, and units

For the purposes of this document, the symbols and designations given in ISO 80000-10, ISO 11929,

ISO/IEC Guide 98-3, and ISO/IEC Guide 99, and the following apply.
A beta activity, in becquerels, of the calibration source
c beta activity concentration, in becquerels per litre
c decision threshold, in becquerels per litre
c detection limit, in becquerels per litre
cc, lower and upper limits of the confidence interval, in becquerels per litre
m mass, in milligrams, of ignited residue from volume, V
m mass, in milligrams, of the sample residue deposited on the planchet
r background count rate, per second
r background count rate, per second, from the alpha window
r sample gross count rate, per second
r sample gross count rate, per second, from the alpha window
r calibration count rate of the beta source, per second
r calibration count rate of the alpha source, per second, from the alpha window
S surface area, in square millimetres, of the planchet
t background counting time, in seconds
t sample counting time, in seconds
t calibration count time of the beta source, in seconds
t calibration count time of the alpha source, in seconds

u(c ) standard uncertainty, in becquerels per litre, associated with the measurement result

U expanded uncertainty, in becquerels per litre, calculated from U = ku(c ), with k = 1, 2 …

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

V volume, in litres, of the water sample
ε counting efficiency for the specified radioactive standard

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

planchet

alpha-beta cross-talk, percentage of alpha count going into the beta window from the alpha

calibration source
2 © ISO 2015 – All rights reserved
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SIST EN ISO 9697:2017
ISO 9697:2015(E)
4 Principle

Gross beta measurement is not intended to give an absolute determination of the activity concentration

of all beta-emitting radionuclides in a test sample, but rather a screening analysis to ensure particular

reference levels of specific beta emitters have not been exceeded. This type of determination is also

known as gross beta index. Gross beta analysis is not expected to be as accurate nor as precise as specific

radionuclide analysis after radiochemical separations.

The sample, taken, handled, and preserved as specified in ISO 5667-1, ISO 5667-3, and ISO 5667-14, is

evaporated to almost dryness, converted to the sulfate form, and ignited at 350 °C. A portion of the

residue is transferred onto a planchet and the beta activity measured by counting in an appropriate

counting assembly, which is calibrated against a suitable beta calibration source, such as potassium-40

40 90 90
( K) or strontium-90/yttrium-90 ( Sr + Y) in equilibrium.

If simultaneous gross alpha and beta measurements are required on the same water sample, the procedure

[2]

specified in this International Standard is common to that of ISO 9696. However, to simultaneously

−2 [3] [4]

measure gross alpha activity, the counting source thickness should be at least 0,1 mg mm . ,

A performance criteria example is given in Annex A .
5 Reagents and equipment
5.1 Reagents

All reagents shall be of recognized analytical grade and shall not contain any detectable beta activity.

NOTE A method for preparing reagent blanks to check for the absence of any endemic radioactivity or

contamination is given in Clause 7.
5.1.1 Water, complying with ISO 3696:1987, grade 3.

5.1.2 Calibration source, the choice of beta calibration source depends on the knowledge of the type

of radioactive contaminant likely to be present in the waters being tested. Among calibration source of

90 40
beta-emitting radionuclides, Sr and K are commonly used.
40 −1 −1 [1]

NOTE The beta activity of K in natural potassium is 27,6 Bq g , i.e. 14,4 Bq g in potassium chloride.

5.1.3 Nitric acid, c(HNO ) = 8 mol/l .
−1 −1

5.1.4 Sulfuric acid, c(H SO ) = 18 mol/l , ρ = 1,84 g/ml , mass fraction w(H SO ) = 95 %.

2 4 2 4
5.1.5 Volatile organic solvents, methanol or acetone.
5.1.6 Calcium sulfate, CaSO .
5.1.7 Vinyl acetate, ((C H O )n).
4 6 2
226 210

CAUTION — As calcium salts can contain trace amounts of Ra and/or Pb, checks for the

presence of these radionuclides shall be made.
5.2 Equipment
Usual laboratory equipment and, in particular, the following:
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SIST EN ISO 9697:2017
ISO 9697:2015(E)

5.2.1 Beta counter, preferably of the gas-flow proportional type, incorporating a plastic scintillation

detector or a silicon-charged particle detector.

When using a gas-flow proportional counter, it is advisable to choose the electronic beta window with minimal

239

beta-alpha cross-talk and correct for the alpha-beta cross-talk using a Pu alpha source. If equipment

other than gas-flow proportional counters is used, then cross-talk can be insignificant and ignored.

If a windowless gas-flow proportional counter is used, carry out regular checks for possible contamination

of the counting system by counting blank samples.

NOTE The particulate nature of the source to be counted can give rise to contamination if operated in a vacuum

(as in the case of silicon-charged particle detector) or gas-flow systems (as used in a proportional counter).

-2 -2

5.2.2 Planchet with counting tray, of surface density at least 2,5 mg/mm (250 mg/cm ), having a

lipped edge and made of stainless steel.

The diameter of the planchet to be used is determined by the counter requirements, i.e. the detector

diameter and source holder dimensions.

NOTE An evenly spread source is required and some analysts find it easier to produce this on a polished

metal surface, whereas others prefer to use an etched or roughened planchet (sand blasting and chemical etching

has been applied for this purpose).
5.2.3 Muffle furnace, capable of being maintained at (350 ± 10) °C.
6 Procedure
6.1 Sampling

Collection, handling, and storage of water samples shall be performed as specified in ISO 5667-1,

ISO 5667-3, and ISO 5667-14.

If the measurement of the activity in the filtered water sample is required, carry out filtration immediately

on collection and before acidification.

NOTE Acidification of the water sample minimises the loss of radioactive material from solution by

adsorption. If carried out before filtration, acidification desorbs radioactive material initially adsorbed on the

particulate material.
6.2 Pretreatment

The determination of the total solids content of the water can be performed to estimate the smallest

volume of water needed for the measurement. Making due allowance for changes in composition due to

ignition at 350 °C and sulfation of the residue, calculate the volume of sample required to produce a mass

per unit area of solid residue slightly in excess of ρ (mg/mm ) given by:
ρ =≥01, (1)

Use this as a guide to determine the volume of sample required for the concentration stage below.

6.3 Concentration stage

Transfer to a beaker a measured volume, V, in litres, of the sample chosen such that after ignition the

value for ρ is at least 0,1 mg/mm .

With very soft waters, it is possible that the volume required to produce ρ ≥ 0,1 mg/mm is impractically

large. In these circumstances, the largest practicable volume should be used or calcium salts should be added.

4 © ISO 2015 – All rights reserved
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