IEC TR 62781:2012

IEC/TR 62781 ®
Edition 1.0 2012-09
TECHNICAL
REPORT
colour
inside
Ultrasonics – Conditioning of water for ultrasonic measurements

IEC/TR 62781:2012(E)
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé Fax: +41 22 919 03 00
CH-1211 Geneva 20 info@iec.ch
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

Useful links:
IEC publications search - www.iec.ch/searchpub Electropedia - www.electropedia.org
The advanced search enables you to find IEC publications The world's leading online dictionary of electronic and
by a variety of criteria (reference number, text, technical electrical terms containing more than 30 000 terms and
committee,…). definitions in English and French, with equivalent terms in
It also gives information on projects, replaced and additional languages. Also known as the International
withdrawn publications. Electrotechnical Vocabulary (IEV) on-line.

IEC Just Published - webstore.iec.ch/justpublished Customer Service Centre - webstore.iec.ch/csc
Stay up to date on all new IEC publications. Just Published If you wish to give us your feedback on this publication
details all new publications released. Available on-line and or need further assistance, please contact the
also once a month by email. Customer Service Centre: csc@iec.ch.

IEC/TR 62781 ®
Edition 1.0 2012-09
TECHNICAL
REPORT
colour
inside
Ultrasonics – Conditioning of water for ultrasonic measurements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
S
ICS 17.140.50 ISBN 978-2-83220-376-7

– 2 – TR 62781 © IEC:2012(E)
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Dissolved gases . 7
3.1 General . 7
3.2 Chemical methods . 8
3.2.1 General . 8
3.2.2 Addition of sodium sulphite . 8
3.3 Physical methods . 9
3.3.1 General . 9
3.3.2 Vacuum degassing . 9
3.3.3 Reduced pressure recirculation . 9
3.3.4 Degassing contactors . 11
3.3.5 Boiling . 11
3.4 Verification methods . 11
3.4.1 General . 11
3.4.2 Electrical verification methods . 12
3.4.3 Optical verification methods . 12
3.5 Re-gassing . 12
4 Dissolved ionic content . 13
4.1 General . 13
4.2 Chemical methods . 13
4.2.1 General . 13
4.2.2 Ion exchange devices . 13
4.3 Physical methods . 13
4.3.1 General . 13
4.3.2 Distillation . 14
4.3.3 Reverse osmosis . 14
4.4 Verification methods . 14
4.5 Reionization . 14
5 Biological content . 15
5.1 General . 15
5.2 Chemical methods . 15
5.2.1 General . 15
5.2.2 Addition of chlorine-based chemicals . 15
5.2.3 Addition of copper-based chemicals . 15
5.2.4 Addition of silver-based chemicals . 16
5.3 Physical methods . 16
5.3.1 General . 16
5.3.2 UV filtration . 16
5.3.3 Cavitation methods . 16
6 Suspended particulate content . 16
6.1 General . 16

TR 62781 © IEC:2012(E) – 3 –
6.2 Physical methods . 17
6.3 Particulate re-contamination . 17
7 Water temperature . 17
7.1 General . 17
7.2 Thermal sources in an ultrasonic measurement tank . 18
8 Examples of low-cost water treatment systems . 18
8.1 Hydrophone measurement water tank. 18
8.2 RFB measurement vessel . 19
Bibliography . 21

Figure 1 – Dissolved oxygen concentration as a function of time for 2, 4 and 6 g/l of
sodium sulphite in de-mineralised water and for different surface areas and volumes of
water . 9
Figure 2 – Dissolved oxygen concentration in water as a function of time during
reduced pressure recirculation degassing . 10
Figure 3 – Re-gassing profile for a body of water following reduced pressure
recirculation degassing . 12
Figure 4 – Example water treatment system for hydrophone measurements . 19
Figure 5 – Example water treatment system for RFB measurements . 20

Table 1 – Conditions for degassing by boiling . 11

– 4 – TR 62781 © IEC:2012(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ULTRASONICS – CONDITIONING OF WATER
FOR ULTRASONIC MEASUREMENTS
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 62781, which is a technical report, has been prepared by IEC technical committee 87:
Ultrasonics.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
87/494A/DTR 87/507/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

TR 62781 © IEC:2012(E) – 5 –
The commi
...