IEC 60704-2-7:2020
(Main)Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 2-7: Particular requirements for fans
Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 2-7: Particular requirements for fans
IEC 60704-2-7:2020 applies to electrical fans (including their accessories and their component parts) for household and similar use, designed for AC or DC supply. The motor, the impeller and their housing, if any, form a single unit. These particular requirements apply to:
– conventional fans,
– table fans,
– pedestal fans,
– ceiling fans,
– bladeless fans,
– wall bracket fans,
– ceiling bracket fans,
– louver fans,
– tower fans,
– ventilating and partition ventilating fans.
This standard does not apply to:
– fans that are part of a ventilation system,
– fans designed exclusively for industrial purposes,
– fans that are part of an appliance (for example cooling fans),
– fans with additional functions (for example heating, humidifying).
Limitations for the use of this test code are given in the scope of IEC 60704-1.
This second edition cancels and replaces the first edition published in 1997. This edition constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) it includes additional fan categories as defined in IEC 60879:2019 and IEC 60665:2018;
b) it includes standard deviations of sound power levels in 1.3;
c) a comparison method has been added;
d) the normative references have been updated (ISO 3744:2010 and ISO 3743-1:2010);
e) it has been adjusted with regard to IEC 60704-1:2010.
This International Standard is to be used in conjunction with IEC 60704 1:2010, Household and similar electrical appliances – Test code for the determination of airborne acoustical noise – Part 1: General requirements. This Part 2-7 supplements or modifies the corresponding clauses in IEC 60704-1:2010, so as to establish the test code for fans.
Appareils électrodomestiques et analogues - Code d'essai pour la détermination du bruit aérien - Partie 2-7: Exigences particulières pour les ventilateurs
L'IEC 60704-2-7:2020 s'applique aux ventilateurs électriques (y compris leurs accessoires et composants) qui sont destinés à des usages domestiques et analogues et conçus pour une alimentation en courant alternatif ou en courant continu. Le moteur, les pales et leur boîtier, le cas échéant, constituent un bloc. Ces exigences particulières s'appliquent aux:
– ventilateurs conventionnels;
– ventilateurs de table;
– ventilateurs sur pied;
– ventilateurs de plafond;
– ventilateurs sans pales;
– ventilateurs à applique murale;
– ventilateurs à applique au plafond;
– ventilateurs rotatifs;
– ventilateurs à colonne;
– aérateurs et aérateurs de cloison.
La présente norme ne s'applique pas aux:
– ventilateurs qui font partie intégrante d'un système de ventilation;
– ventilateurs conçus exclusivement pour des usages industriels;
– ventilateurs qui font partie d'un appareil (par exemple les ventilateurs de refroidissement);
– ventilateurs avec des fonctions supplémentaires (par exemple chauffage, humidification).
Les limites d'utilisation de ce code d'essai sont données dans le domaine d'application de l'IEC 60704-1.
Cette deuxième édition annule et remplace la première édition parue en 1997. Cette édition constitue une révision technique.
Cette édition inclut les modifications majeures suivantes par rapport à l'édition précédente:
a) elle inclut des catégories de ventilateurs supplémentaires, définies dans l'IEC 60879:2019 et l'IEC 60665:2018;
b) des écarts-types sont fournis pour les niveaux de puissance acoustique en 1.3;
c) une méthode comparative a été ajoutée;
d) les références normatives ont été mises à jour (ISO 3744:2010 et ISO 3743-1:2010);
e) le présent document a fait l'objet de réajustements par rapport à l'IEC 60704-1:2010.
Cette Norme Internationale doit être utilisée conjointement avec l'IEC 60704-1:2010, Appareils électrodomestiques et analogues – Code d'essai pour la détermination du bruit aérien – Partie 1: Règles générales. La présente Partie 2-7 complète ou modifie les articles correspondants de l'IEC 60704-1:2010 de façon à établir le code d'essai pour les ventilateurs.
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IEC 60704-2-7 ®
Edition 2.0 2020-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances –
Test code for the determination of airborne acoustical noise –
Part 2-7: Particular requirements for fans
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
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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 corrigendum or an amendment might have been published.
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IEC 60704-2-7 ®
Edition 2.0 2020-01
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances –
Test code for the determination of airborne acoustical noise –
Part 2-7: Particular requirements for fans
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.140.20; 23.120 ISBN 978-2-8322-7799-7
– 2 – IEC 60704-2-7:2020 RLV © IEC 2020
CONTENTS
FOREWORD . 3
1 Scope and object . 7
2 Normative references . 8
3 Terms and definitions . 9
4 Measurement methods and acoustical environments . 9
5 Instrumentation . 12
6 Operation and location of appliances under test . 12
7 Measurement of sound pressure levels . 13
8 Calculation of sound pressure and sound power levels . 15
9 Information to be recorded . 15
10 Information to be reported . 15
Annexes . 17
Annex B (normative) Test enclosure . 17
Bibliography . 17
Figure 101 – Measurement surface – hemisphere – with 10 microphone positions for
partition (wall and window) fans and for wall-mounted table fans . 16
Table 101 – Standard deviations of sound power levels . 8
Table 102 – Standard deviations for declaration and verification . 8
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
TEST CODE FOR THE DETERMINATION OF
AIRBORNE ACOUSTICAL NOISE –
Part 2-7: Particular requirements for fans
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.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.
– 4 – IEC 60704-2-7:2020 RLV © IEC 2020
International Standard IEC 60704-2-7 has been prepared by subcommittee 59L: Small
household appliances, of IEC technical committee 59: Performance of household and similar
electrical appliances.
This second edition cancels and replaces the first edition published in 1997. This edition
constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) it includes additional fan categories as defined in IEC 60879:2019 and IEC 60665:2018;
b) it includes standard deviations of sound power levels in 1.3;
c) a comparison method has been added;
d) the normative references have been updated (ISO 3744:2010 and ISO 3743-1:2010);
e) it has been adjusted with regard to IEC 60704-1:2010.
The text of this standard is based on the following documents:
CDV Report on voting
59L/168/CDV 59L/174/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60704 series, published under the general title Household and
similar electrical appliances – Test code for the determination of airborne acoustical noise,
can be found on the IEC website.
This International Standard is to be used in conjunction with IEC 60704-1:2010, Household
and similar electrical appliances – Test code for the determination of airborne acoustical noise
– Part 1: General requirements.
NOTE When “Part 1” is mentioned in this standard, it refers to IEC 60704-1:2010.
The relevant text of Part 1 as amended by this standard establishes the test code for fans.
This Part 2-7 supplements or modifies the corresponding clauses in IEC 60704-1:2010, so as
to establish the test code for fans. When a particular subclause of Part 1 is not mentioned in
this Part 2-7, that subclause is applicable as far as reasonable. Where this standard states
"addition", "modification" or "replacement", the relevant requirements, test specifications or
explanatory matter in Part 1 should be adapted accordingly.
Subclauses, tables and figures that are numbered starting from 101 are additional to those in
Part 1.
Unless notes are in a new subclause or involve notes in Part 1, they are numbered starting
from 101, including those in a replaced clause or subclause.
Additional annexes are lettered AA, BB, etc.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – IEC 60704-2-7:2020 RLV © IEC 2020
INTRODUCTION
The measuring conditions specified in this Part 2-7 provide for sufficient accuracy in
determining the noise emitted and the comparison of the results of measurements taken by
different laboratories, whilst simulating as far as possible the practical use of household fans.
It is recommended to consider the determination of noise levels as part of a comprehensive
testing procedure covering many aspects of the properties and performance of household
fans.
NOTE As stated in the introduction to IEC 60704-1, this test code is concerned with airborne noise only.
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
TEST CODE FOR THE DETERMINATION OF
AIRBORNE ACOUSTICAL NOISE –
Part 2-7: Particular requirements for fans
1 Scope and object
This clause of Part 1 is applicable except as follows:
1.1 Scope
1.1.1 General
Replacement:
This document applies to electrical fans (including their accessories and their component
parts) for household and similar use, designed for AC or DC supply.
The motor, the impeller and their housing, if any, form a single unit.
These particular requirements apply to:
– conventional fans,
– table fans,
– pedestal fans,
– ceiling fans,
– bladeless fans,
– wall bracket fans,
– ceiling bracket fans,
– louver fans,
– tower fans,
– ventilating and partition ventilating fans.
This standard does not apply to:
– fans that are part of a ventilation system,
– fans designed exclusively for industrial purposes,
– fans that are part of an appliance (for example cooling fans),
– fans with additional functions (for example heating, humidifying).
Limitations for the use of this test code are given in the scope of IEC 60704-1.
1.1.2 Type of noise
Replacement:
The methods specified in ISO 3743-1, ISO 3743-2 and ISO 3744 can be used for measuring
noise emitted by fans.
– 8 – IEC 60704-2-7:2020 RLV © IEC 2020
1.1.3
...
IEC 60704-2-7 ®
Edition 2.0 2020-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances –
Test code for the determination of airborne acoustical noise –
Part 2-7: Particular requirements for fans
Appareils électrodomestiques et analogues –
Code d'essai pour la détermination du bruit aérien –
Partie 2-7: Exigences particulières pour les ventilateurs
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
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les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.
IEC Central Office Tel.: +41 22 919 02 11
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CH-1211 Geneva 20 www.iec.ch
Switzerland
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 corrigendum or an amendment might have been published.
IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary
(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.
need further assistance, please contact the Customer Service
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IEC 60704-2-7 ®
Edition 2.0 2020-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances –
Test code for the determination of airborne acoustical noise –
Part 2-7: Particular requirements for fans
Appareils électrodomestiques et analogues –
Code d'essai pour la détermination du bruit aérien –
Partie 2-7: Exigences particulières pour les ventilateurs
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.140.20; 23.120 ISBN 978-2-8322-7712-6
– 2 – IEC 60704-2-7:2020 © IEC 2020
CONTENTS
FOREWORD . 3
1 Scope and object . 6
2 Normative references . 7
3 Terms and definitions . 8
4 Measurement methods and acoustical environments . 10
5 Instrumentation . 10
6 Operation and location of appliances under test . 10
7 Measurement of sound pressure levels . 12
8 Calculation of sound pressure and sound power levels . 13
9 Information to be recorded . 13
10 Information to be reported . 13
Annexes . 15
Annex B (normative) Test enclosure . 15
Bibliography . 15
Figure 101 – Measurement surface – hemisphere – with 10 microphone positions for
partition (wall and window) fans and for wall-mounted table fans . 14
Table 101 – Standard deviations of sound power levels . 7
Table 102 – Standard deviations for declaration and verification . 7
INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
TEST CODE FOR THE DETERMINATION OF
AIRBORNE ACOUSTICAL NOISE –
Part 2-7: Particular requirements for fans
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.
International Standard IEC 60704-2-7 has been prepared by subcommittee 59L: Small
household appliances, of IEC technical committee 59: Performance of household and similar
electrical appliances.
This second edition cancels and replaces the first edition published in 1997. This edition
constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) it includes additional fan categories as defined in IEC 60879:2019 and IEC 60665:2018;
b) it includes standard deviations of sound power levels in 1.3;
c) a comparison method has been added;
d) the normative references have been updated (ISO 3744:2010 and ISO 3743-1:2010);
e) it has been adjusted with regard to IEC 60704-1:2010.
– 4 – IEC 60704-2-7:2020 © IEC 2020
The text of this standard is based on the following documents:
CDV Report on voting
59L/168/CDV 59L/174/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60704 series, published under the general title Household and
similar electrical appliances – Test code for the determination of airborne acoustical noise,
can be found on the IEC website.
This International Standard is to be used in conjunction with IEC 60704-1:2010, Household
and similar electrical appliances – Test code for the determination of airborne acoustical noise
– Part 1: General requirements.
NOTE When “Part 1” is mentioned in this standard, it refers to IEC 60704-1:2010.
The relevant text of Part 1 as amended by this standard establishes the test code for fans.
This Part 2-7 supplements or modifies the corresponding clauses in IEC 60704-1:2010, so as
to establish the test code for fans. When a particular subclause of Part 1 is not mentioned in
this Part 2-7, that subclause is applicable as far as reasonable. Where this standard states
"addition", "modification" or "replacement", the relevant requirements, test specifications or
explanatory matter in Part 1 should be adapted accordingly.
Subclauses, tables and figures that are numbered starting from 101 are additional to those in
Part 1.
Unless notes are in a new subclause or involve notes in Part 1, they are numbered starting
from 101, including those in a replaced clause or subclause.
Additional annexes are lettered AA, BB, etc.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
...
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