Acoustics - Measurement of sound insulation in buildings and of building elements using sound intensity - Part 3: Laboratory measurements at low frequencies (ISO 15186-3:2002)

ISO 15186-3:2002 specifies a sound intensity method to determine the sound reduction index and the element-normalized level difference of building elements at low frequencies. This method has significantly better reproducibility in a typical test facility than those of ISO 140-3, ISO 140-10 and ISO 15186-1. The results are more independent of the room dimensions of the laboratory and closer to values that would be measured between rooms of volume greater than 300 m3. ISO 15186-3 is applicable in the frequency range 50 Hz to 160 Hz but is mainly intended for the frequency range 50 Hz to 80 Hz.
NOTE For elements faced with thick, porous absorbers, the recommended frequency range is 50 Hz to 80 Hz.
The main differences between the methods of ISO 15186-1 and ISO 15186-3 are that in ISO 15186-3
the sound pressure level of the source room is measured close to the surface of the test specimen, andthe surface opposite the test specimen in the receiving room is highly absorbing and converts the room acoustically into a duct with several propagating cross-modes above the lowest cut-on frequency.
The results found by the method of ISO 15186-3 can be combined with those of ISO 140-3 and ISO 15186-1 to produce data in the frequency range 50 Hz to 5 000 Hz.
The reproducibility of this intensity method is, for all frequencies, estimated to be equal to or better than that found with the method of ISO 140-3 at 100 Hz.
Some comparisons of data obtained with this part of ISO 15186 and with ISO 140-3 are given for information.

Akustik - Bestimmung der Schalldämmung in Gebäuden und von Bauteilen aus Schallintensitätsmessungen - Teil 3: Messungen bei niedrigen Frequenzen im Prüfstand (ISO 15186-3:2002)

1 Anwendungsbereich
1.1 Allgemeines
Der vorliegende Teil von ISO 15186 legt ein Schallintensitätsverfahren zur Bestimmung des Schalldämm-
Maßes und der Norm-Schallpegeldifferenz von Bauteilen bei tiefen Frequenzen fest. Dieses Verfahren besitzt
in einer typischen Prüfeinrichtung eine wesentlich bessere Vergleichpräzision als die Verfahren nach
ISO 140-3, ISO 140-10 und ISO 15186-1. Die Ergebnisse sind von den Raummaßen des Laboratoriums
unabhängiger und liegen näher an Werten, die zwischen Räumen mit einem Volumen von mehr als 300 m3
messbar wären. Dieser Teil von ISO 15186 ist anwendbar im Frequenzbereich von 50 Hz bis 160 Hz, ist
jedoch vor allem für den Frequenzbereich von 50 Hz bis 80 Hz vorgesehen.
ANMERKUNG Für Bauteile, die mit dicken, porösen Schallabsorbern verkleidet sind, ist der empfohlene
Frequenzbereich 50 Hz bis 80 Hz.
Der Hauptunterschied zwischen den Verfahren von ISO 15186-1 und ISO 15186-3 besteht darin, dass in
ISO 15186-3
a) der Schalldruckpegel des Senderaums nahe der Oberfläche des Prüfgegenstands gemessen wird und
b) die Oberfläche gegenüber dem Prüfgegenstand im Empfangsraum stark absorbierend ist und den Raum
akustisch in einen Kanal mit mehreren sich ausbreitenden Quermoden oberhalb der tiefsten unteren
Grenzfrequenz umwandelt.
Um Daten für den Frequenzbereich von 50 Hz bis 5 000 Hz zu erhalten, können die mit dem Verfahren nach
ISO 15186-3 ermittelten Ergebnisse mit den Ergebnissen aus ISO 140-3 und ISO 15186-1 kombiniert werden.
1.2 Präzision
Die Vergleichpräzision dieses Intensitätsverfahrens ist für alle Frequenzen schätzungsweise gleich oder
besser als die Vergleichpräzision der Verfahren aus ISO 140-3 bei 100 Hz.
In Anhang B sind zu Informationszwecken einige Vergleiche der mit dem Verfahren nach diesem Teil von
ISO 15186 und der mit dem Verfahren nach ISO 140-3 ermittelten Daten angegeben.

Acoustique - Mesurage par intensité de l'isolation acoustique des immeubles et des éléments de construction - Partie 3: Mesurages en laboratoire à de basses fréquences (ISO 15186-3:2002)

L'ISO 15186-3:2002 spécifie une méthode d'intensité acoustique pour déterminer l'indice d'affaiblissement acoustique et l'isolement acoustique normalisé des éléments de construction aux basses fréquences. La reproductibilité de cette méthode est nettement meilleure dans un laboratoire type que dans les conditions de l'ISO 140-3:1995, l'ISO 140-10:1991 et l'ISO 15186-1:2000. Les résultats dépendent moins des dimensions des salles d'essai du laboratoire, et sont plus proches des valeurs qui seraient mesurées entre des salles d'un volume supérieur à 300 m3. L'ISO 15186-3:2002 est applicable à la gamme de fréquences comprise entre 50 Hz et 160 Hz, mais elle est principalement destinée à la gamme de fréquences comprise entre 50 Hz et 80 Hz.
Les principales différences entre les méthodes de l'ISO 15186-1:2000 et celles de l'ISO 15186-3:2002 sont les suivantes: dans l'ISO 15186-3:2002, le niveau de pression acoustique de la salle d'émission est mesuré à proximité de la surface de l'éprouvette, et la surface opposée à l'éprouvette dans la salle de réception est hautement absorbante et transforme acoustiquement la salle en un conduit ayant plusieurs modes obliques de propagation au-dessus de la fréquence de coupure la plus basse.
Les résultats obtenus par le biais de la méthode de l'ISO 15186-3:2002 peuvent être combinés à ceux de l'ISO 140‑3:1995 et de l'ISO 15186-1:2000 afin de produire des données dans la gamme de fréquences comprise entre 50 Hz et 5 000 Hz.

Akustika - Merjenje zvočne izolirnosti v stavbah in zvočne izolirnosti gradbenih elementov z uporabo zvočne intenzitete - 3. del: Laboratorijska merjenja pri nizkih frekvencah (ISO 15186-3:2002)

Ta del ISO 15186 določa metodo zvočne intenzitete za določevanje pokazatelja zvočnega zmanjševanja in elementarno normalizirano raven razlike gradbenih elementov pri nizkih frekvencah. Ta metoda ima znatno boljšo obnovljivost v tipičnem preskusnem objektu kot metoda iz ISO 140-3, ISO 140-10 in ISO 15186-1. Rezultati so manj odvisni od mer prostorov laboratorija in bližje vrednostim, ki bi bile izmerjene med prostori z volumnom večjim od 300 m3. Ta del ISO 15186 velja v frekvenčnem razponu od 50 Hz do 160 Hz, vendar je predvsem namenjen za frekvenčni razpon od 50 Hz do 80 Hz. Za elemente, soočene z debelimi, poroznimi absorberji je priporočen frekvenčni razpon od 50 Hz do 80 Hz.

General Information

Status
Published
Publication Date
31-Aug-2010
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Due Date
01-Sep-2010
Completion Date
01-Sep-2010

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SLOVENSKI STANDARD
SIST EN ISO 15186-3:2010
01-december-2010
$NXVWLND0HUMHQMH]YRþQHL]ROLUQRVWLYVWDYEDKLQ]YRþQHL]ROLUQRVWLJUDGEHQLK

HOHPHQWRY]XSRUDER]YRþQHLQWHQ]LWHWHGHO/DERUDWRULMVNDPHUMHQMDSULQL]NLK

IUHNYHQFDK ,62

Acoustics - Measurement of sound insulation in buildings and of building elements using

sound intensity - Part 3: Laboratory measurements at low frequencies (ISO 15186-
3:2002)
Akustik - Bestimmung der Schalldämmung in Gebäuden und von Bauteilen aus

Schallintensitätsmessungen - Teil 3: Messungen bei niedrigen Frequenzen im Prüfstand

(ISO 15186-3:2002)

Acoustique - Mesurage par intensité de l'isolation acoustique des immeubles et des

éléments de construction - Partie 3: Mesurages en laboratoire à de basses fréquences

(ISO 15186-3:2002)
Ta slovenski standard je istoveten z: EN ISO 15186-3:2010
ICS:
17.140.01 $NXVWLþQDPHUMHQMDLQ Acoustic measurements and
EODåHQMHKUXSDQDVSORãQR noise abatement in general
91.120.20 $NXVWLNDYVWDYEDK=YRþQD Acoustics in building. Sound
L]RODFLMD insulation
SIST EN ISO 15186-3:2010 en

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

---------------------- Page: 1 ----------------------
SIST EN ISO 15186-3:2010
---------------------- Page: 2 ----------------------
SIST EN ISO 15186-3:2010
EUROPEAN STANDARD
EN ISO 15186-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2010
ICS 91.120.20
English Version
Acoustics - Measurement of sound insulation in buildings and of
building elements using sound intensity - Part 3: Laboratory
measurements at low frequencies (ISO 15186-3:2002)

Acoustique - Mesurage par intensité de l'isolation Akustik - Bestimmung der Schalldämmung in Gebäuden

acoustique des immeubles et des éléments de construction und von Bauteilen aus Schallintensitätsmessungen - Teil 3:

- Partie 3: Mesurages en laboratoire à de basses Messungen bei niedrigen Frequenzen im Prüfstand (ISO

fréquences (ISO 15186-3:2002) 15186-3:2002)
This European Standard was approved by CEN on 5 August 2010.

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, Croatia, 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

© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15186-3:2010: E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 15186-3:2010
EN ISO 15186-3:2010 (E)
Contents Page

Foreword ..............................................................................................................................................................3

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SIST EN ISO 15186-3:2010
EN ISO 15186-3:2010 (E)
Foreword

The text of ISO 15186-3:2002 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 15186-3:2010 by

Technical Committee CEN/TC 126 “Acoustic properties of building elements and of buildings” 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 2011, and conflicting national standards shall be withdrawn at

the latest by March 2011.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following

countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech

Republic, Denmark, Estonia, Finland, 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 15186-3:2002 has been approved by CEN as a EN ISO 15186-3:2010 without any

modification.
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SIST EN ISO 15186-3:2010
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SIST EN ISO 15186-3:2010
INTERNATIONAL ISO
STANDARD 15186-3
First edition
2002-11-01
Acoustics — Measurement of sound
insulation in buildings and of building
elements using sound intensity —
Part 3:
Laboratory measurements at low
frequencies
Acoustique — Mesurage par intensité de l'isolation acoustique des
immeubles et des éléments de construction —
Partie 3: Mesurages en laboratoire à de basses fréquences
Reference number
ISO 15186-3:2002(E)
© ISO 2002
---------------------- Page: 7 ----------------------
SIST EN ISO 15186-3:2010
ISO 15186-3:2002(E)
PDF disclaimer

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© ISO 2002

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 ISO at the address below or ISO's

member body in the country of the requester.
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Printed in Switzerland
ii ISO 2002 – All rights reserved
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SIST EN ISO 15186-3:2010
ISO 15186-3:2002(E)
Contents Page

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

1.1 General .......................................................................................................................................................... 1

1.2 Precision ........................................................................................................................................................ 1

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

3 Terms and definitions ........................................................................................................................................ 2

4 Instrumentation ................................................................................................................................................. 4

4.1 General .......................................................................................................................................................... 4

4.2 Calibration ..................................................................................................................................................... 5

5 Test arrangement .............................................................................................................................................. 5

5.1 Rooms ........................................................................................................................................................... 5

5.2 Test specimen ................................................................................................................................................ 5

5.3 Mounting conditions ....................................................................................................................................... 6

6 Test procedure .................................................................................................................................................. 6

6.1 General .......................................................................................................................................................... 6

6.2 Generation of sound field .............................................................................................................................. 6

6.3 Measurement of the average sound pressure level over the surface of the test specimen

in the source room ................................................................................................................................................. 6

6.4 Measurement of the average sound intensity level on the receiving side ...................................................... 7

6.5 Background noise .......................................................................................................................................... 9

6.6 Frequency range of measurements ............................................................................................................. 10

7 Expression of results ...................................................................................................................................... 10

8 Test report ...................................................................................................................................................... 10

Annexes

A Qualification .................................................................................................................................................... 11

B Estimated precision of the method.................................................................................................................. 13

Bibliography........................................................................................................................................................... 14

ISO 2002 – All rights reserved iii
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SIST EN ISO 15186-3:2010
ISO 15186-3:2002(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.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.

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.

Attention is drawn to the possibility that some of the elements of this part of ISO 15186 may be the subject of patent

rights. ISO shall not be held responsible for identifying any or all such patent rights.

International Standard ISO 15186-3 was prepared by Technical Committee ISO/TC 43, Acoustics, Subcommittee

SC 2, Building acoustics.

ISO 15186 consists of the following parts, under the general title Acoustics — Measurement of sound insulation in

buildings and of building elements using sound intensity:
— Part 1: Laboratory measurements
— Part 2: In-situ conditions
— Part 3: Laboratory measurements at low frequencies

Annex A forms a normative part of this part of ISO 15186. Annex B is for information only.

iv ISO 2002 – All rights reserved
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SIST EN ISO 15186-3:2010
INTERNATIONAL STANDARD ISO 15186-3:2002(E)
Acoustics — Measurement of sound insulation in buildings and of
building elements using sound intensity —
Part 3:
Laboratory measurements at low frequencies
1 Scope
1.1 General

This part of ISO 15186 specifies a sound intensity method to determine the sound reduction index and the element-

normalized level difference of building elements at low frequencies. This method has significantly better

reproducibility in a typical test facility than those of ISO 140-3, ISO 140-10 and ISO 15186-1. The results are more

independent of the room dimensions of the laboratory and closer to values that would be measured between rooms

of volume greater than 300 m . This part of ISO 15186 is applicable in the frequency range 50 Hz to 160 Hz but is

mainly intended for the frequency range 50 Hz to 80 Hz.

NOTE For elements faced with thick, porous absorbers, the recommended frequency range is 50 Hz to 80 Hz.

The main differences between the methods of ISO 15186-1 and ISO 15186-3 are that in ISO 15186-3

a) the sound pressure level of the source room is measured close to the surface of the test specimen, and

b) the surface opposite the test specimen in the receiving room is highly absorbing and converts the room

acoustically into a duct with several propagating cross-modes above the lowest cut-on frequency.

The results found by the method of ISO 15186-3 can be combined with those of ISO 140-3 and ISO 15186-1 to

produce data in the frequency range 50 Hz to 5 000 Hz.
1.2 Precision

The reproducibility of this intensity method is, for all frequencies, estimated to be equal to or better than that found

100 Hz
with the method of ISO 140-3 at .

Some comparisons of data obtained with the methods of this part of ISO 15186 and ISO 140-3 are given in annex B.

2 Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of

this part of ISO 15186. For dated references, subsequent amendments to, or revisions of, any of these publications

do not apply. However, parties to agreements based on this part of ISO 15186 are encouraged to investigate the

possibility of applying the most recent editions of the normative documents indicated below. For undated references,

the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of

currently valid International Standards.

ISO 140-1, Acoustics — Measurement of sound insulation in buildings and of building elements — Part1:

Requirements for laboratory test facilities with suppressed flanking transmission

ISO 140-3:1995, Acoustics — Measurement of sound insulation in buildings and of building elements — Part 3:

Laboratory measurements of airborne sound insulation of building elements
ISO 2002 – All rights reserved 1
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SIST EN ISO 15186-3:2010
ISO 15186-3:2002(E)

ISO 140-10, Acoustics — Measurement of sound insulation in buildings and of building elements — Part10:

Laboratory measurement of airborne sound insulation of small building elements

ISO 9614-1:1993, Acoustics — Determination of sound power levels of noise sources using sound intensity —

Part 1: Measurement at discrete points
IEC 60942, Electroacoustics — Sound calibrators

IEC 61043:1993, Electroacoustics — Instruments for the measurement of sound intensity — Measurement with pairs

of pressure sensing microphones
3 Terms and definitions

For the purposes of this part of ISO 15186, the following terms and definitions apply.

3.1
average sound pressure level on a test surface

ten times the common logarithm of the ratio of the surface and the time average of the sound pressure squared to the

square of the reference sound pressure

NOTE The surface average is taken over the entire test surface in the source room, including reflecting effects from the test

specimen.
3.2
sound reduction index

ten times the common logarithm of the ratio of the sound power, W , incident on the test specimen to the sound

power, W transmitted through the specimen
� �
R= 10 lg dB (1)
NOTE The expression “sound transmission loss” is also in use.
3.3
sound intensity

time-averaged rate of flow of sound energy per unit area oriented normal to the local particle velocity

NOTE This is a vectorial quantity which is equal to
−→ 1 W
I = [p(t)· u (t)] dt (2)
where
p(t) is the instantaneous sound pressure at a point, in pascals;

u (t) is the instantaneous particle velocity at the same point, in metres per second;

T is the averaging time, in seconds.
2 ISO 2002 – All rights reserved
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SIST EN ISO 15186-3:2010
ISO 15186-3:2002(E)
3.4
normal sound intensity

component of the sound intensity in the direction normal to a measurement surface defined by the unit normal vector

I = I · n (3)

where n is the unit normal vector directed out of the volume enclosed by the measurement surface

3.5
normal sound intensity level

ten times the common logarithm of the ratio of the unsigned value of the normal sound intensity to the reference

intensity I
� �
L = 10 lg dB (4)
−12 2
where I = 10 W/m
3.6
surface-pressure intensity indicator

difference between the sound pressure level, L , and the normal sound intensity level, L , on the measurement

p In
surface, both being time and surface averaged
F = (L −L )dB
(5)
pI p In

NOTE This notation is according to ISO 9614-2. In ISO 9614-1 the notation F is used.

3.7
residual-pressure intensity index
pI0

difference between the indicated sound pressure level, L , and the indicated sound intensity level, L , when the

p I

intensity probe is placed and oriented in a sound field such that the sound intensity is zero

NOTE 1 It is expressed in decibels.
NOTE 2 Details for determining δ are given in IEC 61043:
pI0
δ = (L −L )dB (6)
pI0 p I
3.8
intensity sound reduction index

for one source room and one receiving room with an absorbing back wall, index defined by

� � ��
R =L − 9− L + 10 lg dB (7)
I pS In
where

L is the average sound pressure level over the surface of the test specimen in the source room, in decibels;

L is the average normal sound intensity level over the measurement surface in the receiving room, in

decibels;
ISO 2002 – All rights reserved 3
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SIST EN ISO 15186-3:2010
ISO 15186-3:2002(E)
S is the total area of the measurement surface(s), in square metres;
S is the area of the test specimen under test, in square metres.

NOTE Equation (7) is valid for a test specimen with a reflecting surface in the source room. It will also work satisfactorily for

moderately absorbing surfaces (e.g. surfaces covered with 100 mm thick porous absorbers). For 100 mm to 200 mm thick

absorbers, it is recommended to restrict the frequency range to 50 Hz to 80 Hz. For even thicker absorbers, the equation is no

longer valid.
3.9
intensity element normalized level difference
In,e
difference given by
� � � �
D = − 9− L − 10 lg 10 lgN (8)
L −
In,e pS In
where

is the average sound pressure level over the surface of the test specimen in the source room, in decibels;

L is the average normal sound intensity level over the measurement surface in the receiving room, in

decibels;
A = 10 m ;
S is the total area of the measurement surface(s), in square metres;

is the number of small building element units installed within the measurement surface.

NOTE Equation (8) is valid for a test specimen with a reflecting surface in the source room. It will also work satisfactorily for

moderately absorbing surfaces (e.g. surfaces covered with 100 mm thick porous absorbers). For 100 mm to 200 mm thick

absorbers, it is recommended to restrict the frequency range to 50 Hz to 80 Hz. For even thicker absorbers, the equation is no

longer valid.
3.10
measurement surface

surface totally enclosing the test specimen on the receiving side, scanned or sampled by the probe during the

measurements
3.11
measurement distance

distance between the measurement surface and the specimen in a direction normal to the specimen

3.12
measurement sub-area

part of the measurement surface being measured with the intensity probe, using one continuous scan or discrete

positions
4 Instrumentation
4.1 General
−12 2

The intensity measuring instrumentation shall be capable of measuring intensity levels with reference to 10 W/m

in decibels in one-third-octave bands. The intensity shall be measured in real time when the scanning procedure is

use
...

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