Liquid pumps and pump units - Noise test code - Grades 2 and 3 of accuracy (ISO 20361:2019)

This document specifies all the information necessary to carry out efficiently and under standardized conditions the determination, declaration, and verification of the airborne noise emission of liquid pumps or pump units (see 4.1). It specifies the noise measurement methods and the operating and mounting conditions that shall be used for the test. Noise emission characteristics include emission sound pressure levels at specified positions and the sound power level. The determination of these quantities is necessary for - declaring the noise emission values, and - purpose of noise control at source at the design stage. The determination of these quantities is also necessary for comparing the noise emitted by liquid pumps on the market. The use of this document ensures the reproducibility of the determination of the airborne noise-emission characteristics within specified limits determined by the grade of accuracy of the basic airborne noise measurement method used. Noise measurement methods according to this document are engineering methods (grade 2) and survey methods (grade 3). This document does not deal with the characterization of the structure-borne sound and liquid-borne noise generated by liquid pumps.

Flüssigkeitspumpen und -pumpenaggregate - Geräuschmessung - Genauigkeitsklassen 2 und 3 (ISO 20361:2019)

Dieses Dokument legt alle Informationen fest, um wirkungsvoll und unter genormten Bedingungen die Bestimmung, Angabe und Feststellung der Übereinstimmung der Luftschallgeräuschemission von Flüssigkeitspumpen oder -pumpenaggregaten durchzuführen (siehe 4.1). Es legt die zugelassenen Geräuschmessverfahren und die Betriebs- und Montagebedingungen fest, die zur Prüfung verwendet werden müssen.
Die Geräuschemissionskennwerte schließen den Emissionsschalldruckpegel an einer festgelegten Position und den Schallleistungspegel ein. Die Bestimmung dieser Größen ist erforderlich für:
- die Angabe der Geräuschemissionswerte und
- den ursachenbezogenen Lärmschutz in der Konstruktionsphase.
Die Bestimmung dieser Größen ist auch für den Vergleich der Geräuschemission in Verkehr gebrachter Flüssigkeitspumpen erforderlich.
Die Anwendung dieses Dokuments stellt die Reproduzierbarkeit der Bestimmung von Luftschallgeräuschemissionskennwerten innerhalb der festgelegten Grenzen der Genauigkeitsklasse des verwendeten Luftschallgeräuschmessverfahrens sicher. Geräuschmessverfahren nach diesem Dokument sind Genauigkeitsklasse 2 (en: „engineering method“) und Genauigkeitsklasse 3 (en: „survey method“).
Dieses Dokument behandelt nicht die Analyseverfahren des von Flüssigkeitspumpen erzeugten Körper- und Flüssigkeitsschalls.
ANMERKUNG Dieses Dokument ist in EN 809+A1 für Schallmessungen der Pumpe (oder des Pumpenaggregats) angegeben.

Pompes et groupes motopompes pour liquides - Code d'essai acoustique - Classes de précision 2 et 3 (ISO 20361:2019)

Le présent document spécifie toutes les informations nécessaires pour réaliser efficacement et dans les conditions normalisées, la détermination, la déclaration et la vérification de l'émission de bruit aérien des pompes ou groupes motopompes pour liquides (voir 4.1). Elle spécifie également les méthodes de mesure du bruit ainsi que les conditions de fonctionnement et de montage qui doivent être utilisées pour l'essai.
Les caractéristiques d'émission sonore comprennent les niveaux de pression acoustique d'émission en des points spécifiés ainsi que le niveau de puissance acoustique. La détermination de ces grandeurs est nécessaire pour
—          déclarer les valeurs d'émission sonore, et
—          réduire le bruit à la source au stade de la conception.
La détermination de ces quantités est aussi nécessaire pour comparer le bruit émis par les pompes pour liquides sur le marché.
L'utilisation du présent document assure la reproductibilité de la détermination des caractéristiques d'émission de bruit aérien dans des limites spécifiées, déterminées par la classe de précision de la méthode de base de mesure du bruit aérien utilisée. Les méthodes de mesure du bruit selon le présent document sont des méthodes d'expertise (classe 2) et des méthodes de contrôle (classe 3).
Le présent document ne traite pas de la caractérisation du bruit solidien ni du bruit liquidien générés par les pompes pour liquides.
NOTE       Le présent document est spécifié dans l'EN 809+A1 en ce qui concerne le mesurage du bruit de la pompe (ou du groupe motopompe).

Črpalke za tekočine in črpalni agregati - Preskusni postopki za merjenje hrupa - Razreda točnosti 2 in 3 (ISO 20361:2019)

Ta dokument določa vse potrebne informacije za učinkovito določanje, objavljanje in preverjanje emisij hrupa črpalk za tekočine in črpalnih agregatov, ki bo potekalo pod standardiziranimi pogoji (glej točko 4.1). Določa preskusne postopke za merjenje hrupa ter zahteve za delovanje in priključitev, ki se uporabljajo za preskus. Lastnosti emisij hrupa vključujejo ravni emisij zvočnega tlaka na določenih položajih in raven zvočne moči. Določanje teh količin je potrebno za: – objavljanje vrednosti emisij hrupa; in – namen zvočne zaščite pri viru v fazi projektiranja. Določanje teh količin je prav tako potrebno za primerjavo emisij hrupa različnih črpalk za tekočine na trgu. Uporaba tega dokumenta zagotavlja ponovljivost določanja značilnosti zračnih emisij hrupa v določenih mejah, ki jih določa razred točnosti uporabljene osnovne metode merjenja zračnih emisij hrupa. Metode merjenja hrupa, ki jih določa ta dokument, so inženirske metode (razred 2) in metode raziskovanja (razred 3). Ta dokument ne zajema karakterizacije strukturnega zvoka in vodnega hrupa, ki ju proizvajajo črpalke za tekočine.

General Information

Status
Published
Public Enquiry End Date
31-Jan-2019
Publication Date
22-Sep-2019
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
19-Sep-2019
Due Date
24-Nov-2019
Completion Date
23-Sep-2019

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 20361:2019
01-november-2019
Nadomešča:
SIST EN ISO 20361:2015
Črpalke za tekočine in črpalni agregati - Preskusni postopki za merjenje hrupa -
Razreda točnosti 2 in 3 (ISO 20361:2019)
Liquid pumps and pump units - Noise test code - Grades 2 and 3 of accuracy (ISO
20361:2019)
Flüssigkeitspumpen und -pumpenaggregate - Geräuschmessung - Genauigkeitsklassen
2 und 3 (ISO 20361:2019)
Pompes et groupes motopompes pour liquides - Code d'essai acoustique - Classes de
précision 2 et 3 (ISO 20361:2019)
Ta slovenski standard je istoveten z: EN ISO 20361:2019
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
23.080 Črpalke Pumps
SIST EN ISO 20361:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 20361:2019

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SIST EN ISO 20361:2019


EN ISO 20361
EUROPEAN STANDARD

NORME EUROPÉENNE

September 2019
EUROPÄISCHE NORM
ICS 17.140.20; 23.080 Supersedes EN ISO 20361:2015
English Version

Liquid pumps and pumps units - Noise test code - Grades 2
and 3 of accuracy (ISO 20361:2019)
Pompes et groupes motopompes pour liquides - Code Flüssigkeitspumpen und -pumpenaggregate -
d'essai acoustique - Classes de précision 2 et 3 (ISO Geräuschmessung - Genauigkeitsklassen 2 und 3 (ISO
20361:2019) 20361:2019)
This European Standard was approved by CEN on 30 June 2019.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, 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: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 20361:2019 E
worldwide for CEN national Members.

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SIST EN ISO 20361:2019
EN ISO 20361:2019 (E)
Contents Page
European foreword . 3
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2006/42/EC aimed to be covered . 4

2

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SIST EN ISO 20361:2019
EN ISO 20361:2019 (E)
European foreword
This document (EN ISO 20361:2019) has been prepared by Technical Committee ISO/TC 115 "Pumps"
in collaboration with Technical Committee CEN/TC 197 “Pumps” the secretariat of which is held by
AFNOR.
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 March 2020, and conflicting national standards shall
be withdrawn at the latest by March 2020.
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.
This document supersedes EN ISO 20361:2015.
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 EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZA, which is an integral part 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,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 20361:2019 has been approved by CEN as EN ISO 20361:2019 without any modification.

3

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SIST EN ISO 20361:2019
EN ISO 20361:2019 (E)
Annex ZA
(informative)

Relationship between this European Standard and the essential
requirements of Directive 2006/42/EC aimed to be covered
This European Standard has been prepared under a Commission’s standardization request M/396
"Mandate to CEN and CENELEC for standardisation in the field of machinery" to provide one voluntary
means of conforming to essential requirements of Directive 2006/42/EC of the European Parliament
and of the Council of 17 May 2006 on machinery.
Once this standard is cited in the Official Journal of the European Union under that
Directive 2006/42/EC, compliance with the normative clauses of this standard given in Table ZA.1
confers, within the limits of the scope of this standard, a presumption of conformity with the
corresponding essential requirements of that Directive, and associated EFTA regulations.
Table ZA.1 — Correspondence between this European Standard and Directive 2006/42/EC
Essential requirements of Clause(s)/sub-clause(s) Remarks/Notes
Directive 2006/42/EC of this EN
1.7.4.2 u) 3 to 11 Noise emissions
WARNING 1 — Presumption of conformity stays valid only as long as a reference to this European
Standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2 — Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.

4

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SIST EN ISO 20361:2019
INTERNATIONAL ISO
STANDARD 20361
Third edition
2019-07
Liquid pumps and pumps units —
Noise test code — Grades 2 and 3 of
accuracy
Pompes et groupes motopompes pour liquides — Code d'essai
acoustique — Classes de précision 2 et 3
Reference number
ISO 20361:2019(E)
©
ISO 2019

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Pump family and pump configuration . 2
5 Sound power level determination . 2
5.1 General . 2
5.2 Specific considerations for reference box, measurement surface, position of
microphones, and intensity probe . 4
5.2.1 General. 4
5.2.2 Reference box . 5
5.2.3 Measurement surface and microphone positions . 6
5.2.4 Position of microphones and intensity probes .10
6 Emission sound pressure level determination .10
6.1 Basic standard to be used .10
6.2 Relevant work station .10
7 Uncertainty .10
8 Installation and mounting conditions .11
8.1 General .11
8.2 Noise test situation .11
8.2.1 General.11
8.2.2 Test on site .12
8.2.3 Test on shop test stand .12
8.2.4 Test on a specific facility intended for acoustic measurement .12
9 Operating conditions during noise measurement .12
9.1 General .12
9.2 Pumped liquid .13
9.3 NPSHA value .13
10 Information to be recorded and to be reported .13
10.1 General .13
10.2 Test report .13
11 Declaration and verification of noise emission values .14
Annex A (normative) Pump alone — Measurement surface .15
Annex B (normative) Pump units — Microphone positions for sound pressure level
measurement on the measurement surface for different pump types and sizes .16
Annex C (informative) Example of a dual-number noise declaration .23
Bibliography .24
© ISO 2019 – All rights reserved iii

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SIST EN ISO 20361:2019
ISO 20361:2019(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 of 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 www .iso
.org/iso/foreword .html.
This document was prepared by the European Committee for Standardization (CEN) Technical
Committee CEN/TC 197, Pumps, in collaboration with ISO Technical Committee TC 115, Pumps, in
accordance with the agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 20361:2015), which has been technically
revised. The main changes compared to the previous edition are as follows:
— addition of Clause 7 on measurement uncertainty;
— addition of information in Clause 8 on noise test situation and background noise;
— change of title of previous Clause 9 (now Clause 10).
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

Introduction
The noise emitted by a pump unit can be radiated by the casing of the pump, the driving system
(e.g. motor, gear box, coupling), the piping system, and all the connected structures.
On site, the perceived noise can be significantly increased by reverberation effects or by the radiation
of extraneous sources.
Depending on the type of pump it can be useful to know the following:
a) the noise of the pumping system (including piping);
b) the noise of the pump unit, including the driver and the transmission elements but excluding the
noise of the piping system;
c) the noise emitted by the pump alone, excluding the noise from the driver, transmission elements,
and the piping;
d) the noise emitted by each of those elements in respect to a given requirement or in view of an
efficient sound proofing of the installation.
This document describes methods for the determination of the noise emitted by a pump unit [case b)]
or a pump alone [case c)]. Noise emission is expressed in terms of the sound power level of the machine
and the emission sound pressure level at the relevant work station (see 6.2).
This document is intended to enable the manufacturer to
— show the effectiveness of noise reduction, and
— declare the noise emission levels.
This document is a type-C standard as stated in ISO 12100.
This document is of relevance, in particular, for the following stakeholder groups representing the
market players with regard to machinery safety:
— machine manufacturers (small, medium and large enterprises);
— health and safety bodies (regulators, accident prevention organizations, market surveillance, etc.).
Others can be affected by the level of machinery safety achieved with the means of the document by the
above-mentioned stakeholder groups:
— machine users/employers (small, medium and large enterprises);
— machine users/employees (e.g. trade unions, organizations for people with special needs);
— service providers, e.g. for maintenance (small, medium and large enterprises);
— consumers (in case of machinery intended for use by consumers).
The above-mentioned stakeholder groups have been given the possibility to participate at the drafting
process of this document. The machinery concerned and the extent to which hazards, hazardous
situations or hazardous events are covered are indicated in the Scope of this document.
When requirements of this type-C standard are different from those which are stated in type-A or
type-B standards, the requirements of this type-C standard take precedence over the requirements of
the other standards for machines that have been designed and built according to the requirements of
this type-C standard.
The machinery concerned and the extent to which noise is covered are indicated in the scope of this
document.
© ISO 2019 – All rights reserved v

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SIST EN ISO 20361:2019

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SIST EN ISO 20361:2019
INTERNATIONAL STANDARD ISO 20361:2019(E)
Liquid pumps and pumps units — Noise test code —
Grades 2 and 3 of accuracy
1 Scope
This document specifies all the information necessary to carry out efficiently and under standardized
conditions the determination, declaration, and verification of the airborne noise emission of liquid
pumps or pump units (see 4.1). It specifies the noise measurement methods and the operating and
mounting conditions that shall be used for the test.
Noise emission characteristics include emission sound pressure levels at specified positions and the
sound power level. The determination of these quantities is necessary for
— declaring the noise emission values, and
— purpose of noise control at source at the design stage.
The determination of these quantities is also necessary for comparing the noise emitted by liquid
pumps on the market.
The use of this document ensures the reproducibility of the determination of the airborne noise-
emission characteristics within specified limits determined by the grade of accuracy of the basic
airborne noise measurement method used. Noise measurement methods according to this document
are engineering methods (grade 2) and survey methods (grade 3).
This document does not deal with the characterization of the structure-borne sound and liquid-borne
noise generated by liquid pumps.
NOTE This document is specified in EN 809+A1 for noise measurements of the pump (or pump unit).
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 3743-1:2010, Acoustics — Determination of sound power levels and sound energy levels of noise sources
using sound pressure — Engineering methods for small movable sources in reverberant fields — Part 1:
Comparison method for a hard-walled test room
ISO 3743-2:2018, 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 3744:2010, Acoustics — Determination of sound power levels and sound energy levels of noise sources
using sound pressure — Engineering methods for an essentially free field over a reflecting plane
ISO 3746:2010, Acoustics — Determination of sound power levels and sound energy levels of noise sources
using sound pressure — Survey method using an enveloping measurement surface over a reflecting plane
ISO 4871:1996, Acoustics — Declaration and verification of noise emission values of machinery and
equipment
ISO 9614-1:1993, Acoustics — Determination of sound power levels of noise sources using sound intensity —
Part 1: Measurement at discrete points
© ISO 2019 – All rights reserved 1

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

ISO 9614-2:1996, Acoustics — Determination of sound power levels of noise sources using sound intensity —
Part 2: Measurement by scanning
ISO 11203:1995, Acoustics — Noise emitted by machinery and equipment — Determination of emission
sound pressure levels at a work station and at other specified positions from the sound power level
ISO 17769-1:2012, Liquid pumps and installation — General terms — Definitions, quantities, letter symbols
and units
ISO 17769-2:2012, Liquid pumps and installation — General terms — Definitions, quantities, letter symbols
and units
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 17769-1, ISO 17769-2 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
pump
equipment that is defined as being terminated by its inlet and outlet branches as well as in general its
shaft ends
3.2
pump unit
equipment that is comprised of the pump (3.1) and its driver (e.g. electric motor, steam turbine)

including transmission elements (e.g. coupling, gear), baseplates, and any auxiliary equipment supplied
with the pump
4 Pump family and pump configuration
4.1 Pumps covered by this document comprise of liquid pumps of the rotodynamic and positive
displacement, rotary, and reciprocating types.
4.2 This document provides two possibilities of measurement, either pump alone (see Table 1) or
pump units (see Table 2). In these two cases, the pumps shall be installed
— on site (see 8.2.2), or
— on shop test stand (see 8.2.3), or
— in a specific facility intended for acoustic measurement (see 8.2.4).
4.3 Safety guards, e.g. coupling guards, insulation hoods, etc., if any, shall be installed during noise-
emission determination.
5 Sound power level determination
5.1 General
One of the following grade 2 of accuracy methods for determining the sound power level shall be used:
— ISO 3743-1 or ISO 3743-2;
2 © ISO 2019 – All rights reserved

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

NOTE 1 ISO 3743-1 is based upon a hard-walled room and low background noise. This document gives
specifications to sound pressure level measurement in octave bands in order to calculate the sound
power level.
NOTE 2 ISO 3743-2 is based upon special reverberation test room. This document gives specifications to
sound pressure measurement in octave bands or overall A-weighted sound pressure level measurement in
order to calculate the sound power level.
— ISO 3744;
NOTE 3 ISO 3744 is based upon a non-reverberant environment and low background noise. This document
specifies a method to calculate the sound power level from the measured A-weighted sound pressure levels,
or sound pressure levels in octave or third octave bands.
— ISO 9614-1 or ISO 9614-2.
If it has been shown that the applicability requirements of these grade 2 standards cannot be attained,
e.g. too much background noise, then one of the following grade 3 methods shall be used:
— ISO 3746;
NOTE 4 ISO 3746 is less demanding, it only gives specifications to the measurement of A-weighted sound
pressure levels and provides A-weighted sound power levels with grade 3 of accuracy.
— ISO 9614-1 or ISO 9614-2;
NOTE 5 ISO 9614 (all parts) can be used in all environments, including reverberation and extraneous
noise sources to a large extent. This document gives specifications to sound intensity and sound pressure
measurement. Depending on the level of the reverberation and extraneous noise, it provides the sound
power level either as A-weighted overall level or in octave or third-octave band. For grade 3 measurements,
only the overall A-weighted sound power level is available.
NOTE 6 ISO 9614-1 requires measurements of sound intensity and simultaneously sound pressure level
(at discrete points). In this case, the number of points is generally higher than the number of points used for
the standards based on sound pressure measurements.
NOTE 7 ISO 9614-2 requires measurement of sound intensity and simultaneously sound pressure level by
scanning. This can be made on partial or global surface depending on the configuration of the machine. The
method generally reduces the measurement time.
— ISO/TS 7849-1 or ISO/TS 7849-2.
NOTE 8 ISO/TS 7849 (both parts) are Technical Specifications that can be used only when the
prescriptions of the other methods are not fulfilled. These methods are based upon measurement of
vibration velocity of the relevant parts of the pump or pump unit. ISO/TS 7849-1 provides an estimation
(upper limit) of the A-weighted sound power level and ISO/TS 7849-2 provides the A-weighted sound power
level or sound power level in octave or third octave bands.
For selection of the basic International Standard for determination of the sound power level of a pump,
Table 1 for pumps (pump alone) and Table 2 for pump units shall be used.
The reflecting plane shall be either a hard plane or a surface of water.
The International Standard, indicated in bold letters in Tables 1 and 2, describes the preferred method
and shall be used where practical. If it is not practical, one of the other noted basic International
Standards shall be used.
© ISO 2019 – All rights reserved 3

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SIST EN ISO 20361:2019
ISO 20361:2019(E)

Table 1 — Pumps (pump alone) — Selection of International Standards for determination of
sound power level
Pump power input
P
Test
Grade
kW
arrangement
0,5 < P ≤ 15 15 < P ≤ 75 75 < P ≤ 300 P > 300
b
ISO 3744 ISO 9614
b b
Specific ISO 9614 ISO 9614
2 ISO 3743-2 ISO 3744
a
facility ISO 3744 ISO 3744
b
ISO 9614 ISO 3743-2

b
2 ISO
...

SLOVENSKI STANDARD
oSIST prEN ISO 20361:2019
01-januar-2019
ýUSDONH]DWHNRþLQHLQþUSDOQLDJUHJDWL3UHVNXVQLSRVWRSNL]DPHUMHQMHKUXSD
5D]UHGDWRþQRVWLLQ ,62',6
Liquid pumps and pump units - Noise test code - Grades 2 and 3 of accuracy (ISO/DIS
20361:2018)
Flüssigkeitspumpen und -pumpenaggregate - Geräuschmessung - Genauigkeitsklassen
2 und 3 (ISO/DIS 20361:2018)
Pompes et groupes motopompes pour liquides - Code d'essai acoustique - Classes de
précision 2 et 3 (ISO/DIS 20361:2018)
Ta slovenski standard je istoveten z: prEN ISO 20361
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
23.080 ýUSDONH Pumps
oSIST prEN ISO 20361:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 20361:2019

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oSIST prEN ISO 20361:2019
DRAFT INTERNATIONAL STANDARD
ISO/DIS 20361
ISO/TC 115 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2018-01-08 2018-04-02
Liquid pumps and pumps units — Noise test code —
Grades 2 and 3 of accuracy
Pompes et groupes motopompes pour liquides — Code d'essai acoustique — Classes de précision 2 et 3
ICS: 17.140.20; 23.080
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 20361:2018(E)
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 SUPPORTING DOCUMENTATION. ISO 2018

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COPYRIGHT PROTECTED DOCUMENT
© ISO 2018, 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
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Tel. +41 22 749 01 11
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copyright@iso.org
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Pump family and pump configuration . 2
5 Sound power level determination . 2
5.1 General . 2
5.2 Specific considerations for reference box, measurement surface, position of
microphones, and intensity probe . 4
5.2.1 General. 4
5.2.2 Reference box . 4
5.2.3 Measurement surface and microphone positions . 6
5.2.4 Position of microphones and intensity probes .10
6 Emission sound pressure level determination .10
6.1 Basic standard to be used .10
6.2 Relevant work station .10
6.3 Measurement uncertainty .10
7 Installation and mounting conditions .11
7.1 General .11
7.2 Noise test situation .11
7.2.1 General.11
7.2.2 Test on site .12
7.2.3 Test on shop test stand .12
7.2.4 Test on a specific facility intended for acoustic measurement .12
8 Operating conditions during noise measurement .12
8.1 General .12
8.2 Pumped liquid .13
8.3 NPSHA value .13
9 Information to be recorded and to be reported .13
9.1 General .13
9.2 Test report .13
10 Declaration and verification of noise emission values .13
Annex A (normative) Pump alone — Measurement surface .15
Annex B (normative) Pump units — Microphone positions for sound pressure level
measurement on the measurement surface for different pump types and sizes .16
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2006/42/EC.23
Bibliography .24
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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 World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 115, Pumps.
This third edition cancels and replaces the second edition (ISO 20361:2015), which has been technically
revised.
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Introduction
The noise emitted by a pump unit can be radiated by the casing of the pump, the driving system (e.g.
motor, gear box, coupling), the piping system, and all the connected structures.
On site, the perceived noise can be significantly increased by reverberation effects or by the radiation
of extraneous sources.
Depending on the type of pump it can be useful to know the following:
a) the noise of the pumping system (including piping);
b) the noise of the pump unit, including the driver and the transmission elements but excluding the
noise of the piping system;
c) the noise emitted by the pump alone, excluding the noise from the driver, transmission elements,
and the piping;
d) the noise emitted by each of those elements in respect to a given requirement or in view of an
efficient sound proofing of the installation.
This International Standard describes methods for the determination of the noise emitted by a pump
unit [case b)] or a pump alone [case c)]. Noise emission is expressed in terms of the sound power level of
the machine and the emission sound pressure level at the relevant work station (see 6.2).
This International Standard is intended to enable the manufacturer to
— show the effectiveness of noise reduction, and
— declare the noise emission levels.
This International Standard is a type C standard as stated in ISO 12100.
When provisions of this type C standard are different from those which are stated in A or B standards,
the provisions of this type C standard take precedence.
The machinery concerned and the extent to which noise is covered are indicated in the scope of this
International Standard.
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DRAFT INTERNATIONAL STANDARD ISO/DIS 20361:2018(E)
Liquid pumps and pumps units — Noise test code —
Grades 2 and 3 of accuracy
1 Scope
This International Standard specifies all the information necessary to carry out efficiently and under
standardized conditions the determination, declaration, and verification of the airborne noise emission
of liquid pumps or pump units (see 4.1). It specifies the noise measurement methods and the operating
and mounting conditions that shall be used for the test.
Noise emission characteristics include emission sound pressure levels at specified positions and the
sound power level. The determination of these quantities is necessary for
— declaring the noise emission values, and
— purpose of noise control at source at the design stage.
The determination of these quantities is also necessary for comparing the noise emitted by liquid
pumps on the market.
The use of this International Standard ensures the reproducibility of the determination of the airborne
noise-emission characteristics within specified limits determined by the grade of accuracy of the basic
airborne noise measurement method used. Noise measurement methods according to this International
Standard are engineering methods (grade 2) and survey methods (grade 3).
This International Standard does not deal with the characterization of the structure-borne sound and
liquid-borne noise generated by liquid pumps.
NOTE This International Standard is specified in EN 809+A1 for noise measurements of the Pump (or
Pump Unit).
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 3743-1, Acoustics — Determination of sound power levels and sound energy levels of noise sources
using sound pressure — Engineering methods for small movable sources in reverberant fields — Part 1:
Comparison method for a hard-walled test room
ISO 3743-2, 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 3744, Acoustics — Determination of sound power levels and sound energy levels of noise sources using
sound pressure — Engineering methods for an essentially free field over a reflecting plane
ISO 3746, Acoustics — Determination of sound power levels and sound energy levels of noise sources using
sound pressure — Survey method using an enveloping measurement surface over a reflecting plane
ISO 4871:1996, Acoustics — Declaration and verification of noise emission values of machinery and
equipment
ISO 9614-1, Acoustics — Determination of sound power levels of noise sources using sound intensity —
Part 1: Measurement at discrete points
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ISO 9614-2, Acoustics — Determination of sound power levels of noise sources using sound intensity —
Part 2: Measurement by scanning
ISO 11203, Acoustics — Noise emitted by machinery and equipment — Determination of emission sound
pressure levels at a work station and at other specified positions from the sound power level
ISO 17769 (all parts), Liquid pumps and installation — General terms — Definitions, quantities, letter
symbols and units
ISO/TS 7849-1, Acoustics — Determination of airborne sound power levels emitted by machinery using
vibration measurement — Part 1: Survey method using a fixed radiation factor
ISO/TS 7849-2, Acoustics — Determination of airborne sound power levels emitted by machinery
using vibration measurement — Part 2: Engineering method including determination of the adequate
radiation factor
3 Terms and definitions
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.
3.1
pump
equipment that is defined as being terminated by its inlet and outlet branches as well as in general its
shaft ends
3.2
pump unit
equipment that is comprised of the pump (3.1) and its driver (e.g. electric motor, steam turbine)

including transmission elements (e.g. coupling, gear), baseplates, and any auxiliary equipment supplied
with the pump
4 Pump family and pump configuration
4.1 Pumps covered by this International Standard comprise of liquid pumps of the rotodynamic and
positive displacement, rotary, and reciprocating types.
4.2 This International Standard provides two possibilities of measurement, either pump alone (see
Table 1) or pump units (see Table 2). In these two cases, the pumps shall be installed
— on site (see 7.2.2), or
— on shop test stand (see 7.2.3), or
— in a specific facility intended for acoustic measurement (see 7.2.4).
4.3 Safety guards, e.g. coupling guards, insulation hoods etc., if any, shall be installed during noise-
emission determination.
5 Sound power level determination
5.1 General
One of the following grade 2 of accuracy methods for determining the sound power level shall be used:
— ISO 3743-1 or ISO 3743-2;
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NOTE 1 ISO 3743-1 is based upon a hard-walled room and low background noise. This International
Standard gives specifications to sound pressure level measurement in octave bands, in order to calculate the
sound power level.
NOTE 2 ISO 3743-2 is based upon special reverberation test room. This International Standard gives
specifications to A-weighted sound pressure level measurement in order to calculate the sound power level.
— ISO 3744;
NOTE 3 ISO 3744 is based upon a non-reverberant environment and low background noise. This
International Standard specifies a method to calculate the sound power level from the measured A-weighted
sound pressure levels, or sound pressure levels in octave or third octave bands.
— ISO 9614-1 or ISO 9614-2.
If it has been shown that the applicability requirements of these grade 2 standards cannot be
attained, e.g. too much background noise, then one of the following grade 3 methods shall be used:
— ISO 3746;
NOTE 4 ISO 3746 is less demanding, it only gives specifications to the measurement of A-weighted sound
pressure levels and provides A-weighted sound power levels with grade 3 of accuracy.
— ISO 9614-1 or ISO 9614-2;
NOTE 5 ISO 9614 (all parts) can be used in all environments, including reverberation and extraneous
noise sources to a large extent. This International Standard gives specifications to sound intensity and
sound pressure measurement. Depending on the level of the reverberation and extraneous noise, it provides
the sound power level either as A-weighted overall level or in octave or third-octave band. For grade 3
measurements, only the overall A-weighted sound power level is available.
NOTE 6 ISO 9614-1 requires measurements of sound intensity and simultaneously sound pressure level
(at discrete points). In this case, the number of points is generally higher than the number of points used for
the standards based on sound pressure measurements.
NOTE 7 ISO 9614-2 requires measurement of sound intensity and simultaneously sound pressure level by
scanning. This can be made on partial or global surface depending on the configuration of the machine. The
method generally reduces the measurement time.
— ISO/TS 7849-1 or ISO/TS 7849-2.
NOTE 8 ISO/TS 7849 (both parts) are Technical Specifications that can be used only when the
prescriptions of the other methods are not fulfilled. These methods are based upon measurement of
vibration velocity of the relevant parts of the pump or pump unit. ISO/TS 7849-1 provides an estimation
(upper limit) of the A-weighted sound power level and ISO/TS 7849-2 provides the A-weighted sound power
level or sound power level in octave or third octave bands.
For selection of the basic International Standard for determination of the sound power level of a pump,
Table 1 for pumps (pump alone) and Table 2 for pump units shall be used.
The reflecting plane shall be either a hard plane or a surface of water.
The International Standard, indicated in bold letters in Tables 1 and 2, describes the preferred method
and shall be used where practical. If it is not practical, one of the other noted basic International
Standards shall be used.
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Table 1 — Pumps (pump alone) — Selection of International Standards for determination of
sound power level
Pump power input
Test
Grade P
arrangement
kW
0,5 < P ≤ 15 15 < P ≤ 75 75 < P ≤ 300 P > 300
b
ISO 3744 ISO 9614
b b
Specific ISO 9614 ISO 9614
2 ISO 3743-2 ISO 3744
a
facility ISO 3744 ISO 3744
b
ISO 9614 ISO 3743-2
Shop test
b
2 ISO 9614 impractical
stand
b
ISO 9614
b
3 ISO 9614
ISO 3746
b
On site 2 ISO 9614 impractical
b b
ISO 9614 ISO 9614
3
ISO 3746 ISO/TR 7849
a
A facility can be qualified as specifically designed for noise measurements if it yields grade 2 measurements.
b
ISO 9614 means ISO 9614-1 or ISO 9614-2.
Table 2 — Pump unit — Selection of standards for determination of sound power level
Pump power input
Test
Grade P
arrangement
kW
0,5 < P ≤ 15 15 < P ≤ 75 75 < P ≤ 300 P > 300
ISO 3744
b
Specific ISO 3744 ISO 9614
2 ISO 3743-2
a b
facility ISO 9614 ISO 3744
b
ISO 9614
ISO 3744
b
Shop test ISO 3744 ISO 9614
c b
2 ISO 3743-1 ISO 9614
b
stand ISO 9614 ISO 3744
b
ISO 9614
b b
ISO 3746 ISO 9614 ISO 9614
3
b
ISO 9614 ISO 3746 ISO 3746
b
ISO 9614
b
On site 2 ISO 9614
ISO 3744
b
ISO 3746 ISO 9614
3
b
ISO 9614 ISO 3746
a
A facility can be qualified as specifically designed for noise measurements if it yields grade 2 measurements.
b
ISO 9614 means ISO 9614-1 or ISO 9614-2.
c
ISO 3743-1 can be used for pump units in a shop test stand at the condition that pipings are properly lagged.
5.2 Specific considerations for reference box, measurement surface, position of
microphones, and intensity probe
5.2.1 General
When ISO 3744, ISO 3746, or ISO 9614 is used, 5.2.2 to 5.2.4 apply.
5.2.2 Reference box
The reference box is a hypothetical surface, the smallest simple volume (parallelepiped, box, cylinder,
etc.) containing the pump unit or pump and the flanges of the machine but excluding the pipings for the
pump unit and pipings, transmission elements, and driver for pumps (pump alone) and small individual
components of the source that do not contribute to the sound radiation. For ISO 3744 and ISO 3746, the
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reference box is a parallelepiped. The box encloses the source and terminates on the reflecting plane
(hard ground or water). For examples of reference boxes see Figures 1 and 2.
Key
1 reflecting plane
2 reference box
3 pump
4 driver
Figure 1 — Reference box for pump unit (example)
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Key
1 reflecting plane
2 reference box
3 pump
4 driver
Figure 2 — Reference box for pump (alone) (example)
5.2.3 Measurement surface and microphone positions
The measurement surface is a surface enveloping the reference box at a given distance to the box.
The distance between the measurement surface and the reference box is called the measurement
distance. It depends on the basic method used.
— For ISO 3744 and ISO 3746, both of which are based on sound pressure level measurements, the
distance shall be chosen equal to 1 m.
Where the background noise requirements of these International Standards are not met, a distance
smaller than 1 m but larger than 0,25 m can be chosen.
— For ISO 9614-1 and ISO 9614-2, both of which are based on a sound intensity measurement, the
distance shall be
— d ≥ 0,5 m for ISO 9614-1;
1
— 0,2 m ≤ d ≤ 0,5 m for ISO 9614-2.
2
For the measurement surface, see Figures 3 to 6 and Annex A.
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Dimensions in metres
Key
1 reflecting plane
2 upper measurement surface
3 reference box
4 median measurement surface
× microphone positions for grade 3
⊗ additional microphone positions for grade 2
L height of the reference box, equal to the highest pump-unit point
h height, expressed in metres, of the median measurement plane: h = (L + 1)/2
h height, expressed in metres, of the upper measurement plane: h = L + 1
1 1
Figure 3 — Typical measurement surface and planes for sound pressure level measurement for
a pump unit
In the case of the pump alone, Figure 4 indicates the position of the measurement surface. No
microphone shall be placed on the face of this surface that looks at the motor (see also Annex A).
The practical microphone positions for different pump types and sizes are given in Annex B.
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Key
1 reflecting plane
2 upper measurement surface
3 reference box
4 median measurement surface
× microphone positions for grade 3
⊗ additional microphone positions for grade 2
L height of the reference box, equal to the highest pump-unit point
h height, expressed in metres, of the median measurement plane: h = (L + 1)/2
h height, expressed in metres, of the upper measurement plane: h = L + 1
1 1
Figure 4 — Typical measurement surfaces and planes for sound pressure level measurement
for pump alone
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Key
1 reflecting plane
2 measurement surface for fixed points
3 closer measurement surface for scanning
4 reference box
d ≥0,5 m
1
h L + d
1 1
d 0,2 m to 0,5 m
2
Figure 5 — Typical measurement surfaces and planes for sound intensity measurement for
pump unit
Key
1 measurement surface for fixed points
2 closer measurement surface for scanning
3 reference box
d ≥0,5 m
1
h L + d
1 1
d 0,2 m to 0,5 m
2
Figure 6 — Typical measurement surface for sound intensity measurement for pump alone
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5.2.4 Position of microphones and intensity probes
The position of the microphones or intensity probes on the measurement surface shall be those
specified by the basic measurement standard used. For typical microphone positions see Figures 3 to
6 and Annex B. However, if necessary, one or several of these positions shall be altered in order to fulfil
the following requirements.
— The distance between a microphone and the surface of a pipe shall not be smaller than 0,5 m.
— The distance between the intensity probe and the surface of a pipe shall not be smaller than 0,2 m.
If a microphone position falls on the axis of a piping or centreline of the shaft, this point shall not be
measured. It shall be replaced by two points located at 45° to the axis as shown in Figure 7.
a) Incorrect arrangement b) Correct arrangement
Key
× microphone positions for measurements
a
No measurement shall be made at this point.
Figure 7 —
...

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