EN ISO 3743-2:2009

SLOVENSKI STANDARD
01-november-2009
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SIST EN ISO 3743-2:1997
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Acoustics - Determination of sound power levels of noise sources using sound pressure -
Engineering methods for small, movable sources in reverberant fields - Part 2: Methods
for special reverberation test rooms (ISO 3743-2:1994)
Akustik - Bestimmung der Schalleistungspegel von Geräuschquellen aus
Schalldruckmessungen - Verfahren der Genauigkeitsklasse 2 für kleine, transportable
Quellen in Hallfeldern - Teil 2: Verfahren für Sonder-Hallräume (ISO 3743-2:1994)
Acoustique - Détermination des niveaux de puissance acoustique émis par les sources
de bruit à partir de la pression acoustique - Méthodes d'expertise en champ réverbéré
applicables aux petites sources transportables - Partie 2: Méthodes en salle d'essai
réverbérante spéciale (ISO 3743-2:1994)
Ta slovenski standard je istoveten z: EN ISO 3743-2:2009
ICS:
17.140.01 $NXVWLþQDPHUMHQMDLQ Acoustic measurements and
EODåHQMHKUXSDQDVSORãQR noise abatement in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 3743-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2009
ICS 17.140.01 Supersedes EN ISO 3743-2:1996
English Version
Acoustics - Determination of sound power levels of noise
sources using sound pressure - Engineering methods for small,
movable sources in reverberant fields - Part 2: Methods for
special reverberation test rooms (ISO 3743-2:1994)
Acoustique - Détermination des niveaux de puissance Akustik - Bestimmung der Schalleistungspegel von
acoustique émis par les sources de bruit à partir de la Geräuschquellen aus Schalldruckmessungen - Verfahren
pression acoustique - Méthodes d'expertise en champ der Genauigkeitsklasse 2 für kleine, transportable Quellen
réverbéré applicables aux petites sources transportables - in Hallfeldern - Teil 2: Verfahren für Sonder-Hallräume (ISO
Partie 2: Méthodes en salle d'essai réverbérante spéciale 3743-2:1994)
(ISO 3743-2:1994)
This European Standard was approved by CEN on 13 July 2009.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 3743-2:2009: E
worldwide for CEN national Members.

Contents Page
Foreword .3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC .4
Annex ZB (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC .5

Foreword
The text of ISO 3743-2:1994 has been prepared by Technical Committee ISO/TC 43 “Acoustics” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 3743-2:2009 by
Technical Committee CEN/TC 211 “Acoustics” the secretariat of which is held by DS.
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 January 2010, and conflicting national standards shall be withdrawn at
the latest by January 2010.
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.
This document supersedes EN ISO 3743-2:1996.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EC Directives.
For relationship with EC Directives, see informative Annexes ZA and ZB, which are integral parts of this
document.
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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 3743-2:1994 has been approved by CEN as a EN ISO 3743-2:2009 without any modification.
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 98/37/EC, amended by 98/79/EC on machinery.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity
with the relevant Essential Requirements of that Directive and associated EFTA regulations.
WARNING - Other requirements and other EU Directives may be applicable to the product(s) falling within the
scope of this standard.
Annex ZB
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 2006/42/EC on machinery.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard confers, within the limits of the scope of this standard, a presumption of conformity
with the relevant Essential Requirements of that Directive and associated EFTA regulations.
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling within
the scope of this standard.
INTERNATIONAL
ISO
STANDARD
3743-2
First edition
1994-11-01
Acoustics - Determination of Sound
power levels of noise sources using Sound
- Engineering methods for
pressure
small, -movable sources in reverberant
fields -
Part 2:
Methods for special reverberation test rooms
Acoustique - Determination des niveaux de puissance acoustique 6mis
par les sources de bruit ~9 partir de Ia Pression acoustique - Methodes
d ’expertise en champ r&erb&6 applicables aux petites sources
transportables -
Partie 2: Methodes en salle d ’essai rkverbkan te spkciale
Reference number
ISO 37432:1994(E)
ISO 3743-2: 1994(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. Esch member body interested in a subject for
which a technical committee has been established has the right to be re-
presented 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
(1 EC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard ISO 3743-2 was prepared by Technical Committee
lSO/TC 43, Acoustics, Subcommittee SC 1, Noise.
This first edition cancels and replaces the ISO 3743:1988, of which it
constitutes a minor revision.
ISO 3743 consists of the following Parts, under the general title
Acoustics - Determination of Sound power levels of noise sources using
Sound pressure - Engineering methods for small, movable sources in
reverberan t fields:
- Part 7: Comparison method for hard-walled test rooms
- Part 2: Methods for special reverberation test rooms
Annex A forms an integral patt of this part of ISO 3743. Annexes B, C and
D are for information only.
0 ISO 1994
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronie or mechanical, including photocopying and
microfilm, without Permission in writing from the publisher.
International Organization for Standardization
Gase Postale 56 l CH-l 211 Geneve 20 l Switzerland
Printed in Switzerland
0 ISO
ISO 3743-2: 1994(E)
0.1 ISO 3743 is one of the ISO 3740 series, which specifies various
methods for determining the Sound power Ievels of machines, equipment
and sub-assemblies. These basic Standards specify the acoustical re-
quirements for measurements appropriate for different test environments
as shown in table 0.1. When selecting one of the methods of the ISO 3740
series, it is necessary to select the most appropriate for the conditions and
purposes of the noise test. General guidelines to assist in the selection
are provided in ISO 3740. The ISO 3740 series gives only general prin-
ciples regarding the operating and mounting conditions of the machine or
equipment under test. Reference should be made to the noise test code
for a specific type of machine or equipment, if available, for specifications
on mounting and operating conditions.
0.2 The method given in this part of ISO 3743 enables measurement
of Sound pressure levels with A-weighting and in octave bands at pre-
scribed fixed microphone positions or along prescribed paths. lt allows
determination of A-weighted Sound power levels or Sound power levels
with other weighting and octave-band Sound power levels. Quantities
which cannot be determined are the directivity characteristics of the
Source and the temporal Pattern of noise radiated by sources emitting
non-steady noise.
0.3 Parts 1 and 2 of ISO 3743 specify engineering methods for deter-
mining the A-weighted and octave-band Sound power levels of small noise
sources. The methods are applicable to small machines, devices, com-
ponents and sub-assemblies which tan be installed in a special reverber-
ation test room or in a hard-walled test room with prescribed acoustical
characteristics. The methods are particularly suitable for small items of
portable equipment; they are not intended for larger pieces of stationary
equipment which, due to their manner of Operation or installation, cannot
readily be moved into the test room and operated as in normal usage. The
procedures are intended to be used when an engineering grade of accu-
racy is desired without requiring the use of laboratoty facilities.
0.4 In ISO 3743-1, a comparison method is used to determine the
octave-band Sound power levels of the Source. The spatial average
(octave-band) Sound pressure Ievels produced by the Source under test
are compared to the spatial average (octave-band) Sound pressure levels
produced by a reference Sound Source of known Sound power output. The
differente in Sound pressure levels is equal to the differente in Sound
power levels if conditions are the Same for both sets of measurements.
The A-weighted Sound power level is then calculated from the octave-
band Sound power levels.
. . .
Ill
ISO 3743-2: 1994( lg 0 ISO
The requirements to be fulfilled by the special reverberation test room for
measurements in accordance with this part of ISO 3743 are significantly
more restrictive than those placed on the hard-walled test room by the
comparison method of ISO 3743-1.

International
Classification of Sound power levels Optional information
Test environment Volume of Source Character of noise
Standard methodl) available
obtainable
Steady, broad-band
Reverberation room
Precision In one-third-octave A-weighted Sound
Steady, discrete fre-
meeting specified
(grade 1) or octave bands power ievel
quency or narrow-
requirements
Preferably less than
band
1 % of
...