ISO 140-4:1978

Acoustics — Measurement of sound insulation in buildings and of building elements — Part 4: Field measurements of airborne sound insulation between rooms

Acoustique — Mesurage de l'isolation acoustique des immeubles et des éléments de construction — Partie 4: Mesurage sur place de l'isolation aux bruits aériens entre les pièces

Akustika - Merjenje zvočne izolirnosti v zgradbah in zvočne izolirnosti gradbenih elementov - 4. del: Terenska merjenja izolirnosti med prostori pred zvokom v zraku

General Information

• Status: Withdrawn
• Publication Date: 30-Jun-1978
• Withdrawal Date: 30-Jun-1978
• ICS: 91.120.20 - Acoustics in building. Sound insulation
• Technical Committee: ISO/TC 43 - Acoustics
• Drafting Committee: ISO/TC 43 - Acoustics
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 20-Aug-1998
• Ref Project: SIST ISO 140-4:1997 - Acoustics -- Measurement of sound insulation in buildings and of building elements -- Part 4: Field measurements of airborne sound insulation between rooms

Relations

• Revised: ISO 140-4:1998 - Acoustics — Measurement of sound insulation in buildings and of building elements — Part 4: Field measurements of airborne sound insulation between rooms
• Effective Date: 15-Apr-2008

Standards Content (Sample)

INTERNATIONAL STANDARD 140 I IV
~~ ~~~~ ~~
INTERNATIONAL ORGANIZATION FOR STANDARDlZATION*MEWYHAPOLlHAR OPrAHH3AUMR no CTAHAAPTH3AUIIH.ORGANlSATlON INTERNATIONALE DE NORMALISATION
L
Acoustics - Measurement of sound insulation in buildings
and of building elements -
Part IV : Field measurements of airborne sound insulation
between rooms
Acoustique - Mesurage de l'isolation acoustique des immeubles et des 6ltfments de construction -
Partie IV : Mesurage sur place de l'isolation aux bruits atfriens entre les pitkes
First edition - 1978-07-15
U DC 534.833.522.4.08 Ref. No. IS0 140/1\1-1978 (E)
Descriptors : acoustics, acoustic measurement, acoustic insulation, buildings, structural members, rooms, tests, testing conditions, field
tests, airborne sound.
Price based on 5 pages

---------------------- Page: 1 ----------------------
FOREWORD
IS0 (the International Organization for Standardization) is a worldwide federation
of national standards institutes (IS0 member bodies). The work of developing
International Standards is carried out through IS0 technical committees. Every
member body interested in a subject for which a technical committee has been set
up 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.
Draft International Standards adopted by the technical committees are circulated
to the member bodies for approval before their acceptance as International
Standards by the IS0 Council.
International Standard IS0 140/IV was developed by Technical Committee
ISO/TC 43, Acoustics, and was circulated to the member bodies in May 1976.
It has been approved by the member bodies of the following countries
Australia India Romania
Austria Israel South Africa, Rep. of
Belgium Italy Sweden
Canada Japan Switzerland
Korea, Rep. of
Czechoslovakia Turkey
Denmark Mexico United Kingdom
Finland
Netherlands U.S.A.
France New Zealand U.S.S. R.
Germany Norway
Hungary Poland
The member body of the following country expressed disapproval of the document
on technical grounds :
Spain
This International Standard, together with International Standards IS0 140/1, III,
VI and VII, cancel and replace IS0 Recommendation R 140-1960, of which they
constitute a technical revision.
Annexes B and C are integral parts of this International Standard.
O International Organization for Standardization, 1978 O
Printed in Switzerland

---------------------- Page: 2 ----------------------
INTERNATIONAL STANDARD IS0 140/1V-1978 (E)
Acoustics - Measurement of sound insulation in buildings
and of building elements -
Part IV : Field measurements of airborne sound insulation
between rooms
O INTRODUCTION
IS0 14O/V, Acoustics - Measurement of sound insulation
in buildings and of building elements - Part V : Field
The purpose of this International Standard is
measurements of airborne sound insulation of facade
elements and facades.
- to give procedures to measure the sound insulation
L
between two rooms in buildings, thus making it possible
ISO/R 354, Measurement of absorption coefficients in a
to check whether the desired acoustical conditions have
reverberation room.
been obtained;
ISOIR 71 7, Rating of sound insulation for dwellings.
- to give field procedures to determine whether
building elements have met specifications and to check I EC Publication 225, Octave, half-octave and third-octave
whether faults have occurred during construction. band filters intended for the analysis of sound and vi-
brations.
1 SCOPE AND FIELD OF APPLICATION
This International Standard specifies field methods for
3 DEFINITIONS
measuring the airborne sound insulation properties of
3.1 average sound pressure level in a room : Ten times the
interior walls, floors and doors between two rooms under
common logarithm of the ratio of the space and time
diffuse sound field conditions in both rooms and for deter-
average of the sound pressure squared to the square of the
mining the protection afforded to the occupants of the
reference sound pressure, the space average being taken
building.
over the entire room with the exception of those parts
The results obtained can be used to compare sound insu-
where the direct radiation of a sound source or the near
lation between rooms and to compare actual sound in-
field of the boundaries (wall, etc.) is of significant influence.
sulation with specified requirements.
This quantity is denoted by L :
When determining the protection afforded to the occupants
L
of the building, the standardized level difference (see 3.3) L = 1019 p; +p; +. . .
dB
(1)
is appropriate.
When determining the sound insulation properties of a
where
building element, the apparent sound reduction index
(see 3.4) is used.
p,, p2, . . .,pn are the r.m.s. sound pressures at n
different positions in the room;
NOTES
1 Laboratory measurements of airborne sound insulation of build-
po = 20 pPa is the reference sound pressure.
IS0 140/111.
ing elements are dealt with in
2 Field measurements of airborne sound insulation of facade
3.2 level difference : The difference in the space and time
IS0 140/V.
elements and facades are dealt with in
average sound pressure levels produced in two rooms by
one or more sound sources in one of them. This quantity
is denoted by D :
2 REFERENCES
D= Ll - L2 . . . (2)
IS0 140/11, Acoustics - Measurement of sound insulation
in buildings and of building elements - Part II : Statement
where
of precision requirements.
L1 is the average sound pressure level in the source
IS0 14011 I I, Acoustics - Measurement of sound insulation
room;
in buildings and of building elements - Part III : Labor-
atory measurements of airborne sound insulation of build-
L2 is the average sound pressure level in the receiving
ts.
ing elemen room.
1

---------------------- Page: 3 ----------------------
IS0 140/1\/-1978 (E)
3.3 standardized level difference : The level difference where
corresponding to a reference value of the reverberation time
S is the area of the test specimen;
is denoted by DnT :
in the receiving room. This quantity
A is the equivalent absorption area in the receiving
T
I
D,, = D + 10 lg ~d0 room.
(3)
‘O
In the case of evaluation of R’ of a door S is the area of the
where
free opening in which the door including the frame is
mounted. It must be proved that the sound transmission
D is the level difference;
through the rest of the surrounding wall is negligible.
T is the reverberation time in the receiving room;
In the case of staggered rooms, S is that part of the area of
the partition common to both rooms; if, however, the
To is the reference reverberation time.
common area is less than 10m2, the value of S for in-
For dwellings, To is given by
sertion in equation (6) shall be 10 m2 but the measurement
results shall not be used for comparison with results
To = 0,5 s . . . (4)
obtained by measurement in laboratory.
NOTES
NOTE - In the apparent sound reduction index, the sound power
1 The standardizing of the level difference to a reverberation time
is related to the sound power
transmitted into the receiving room
-
of 0.5s takes into account that in dwellings with furniture the
incident on the common partition irrespective of actual conditions
reverberation time has been found - nearly independently of
of transmission.
the volume and of frequency - to be equal to 0.5 s. With this
The apparent sound reduction index is independent of the measur-
standardizing, D,, is dependent on the direction of the sound
transmission if the two rooms have different volumes, ing direction between the rooms if the sound fields are diffuse in
both rooms.
2 The standardizing of the level difference to the reverberation
time in the receiving room of To = 0.5 s is equivalent to standard-
izing the level difference with respect to an equivalent absorption
area of :
4 EQUIPMENT
Ag = 0.32 V
The equipment shall be suitable for meeting the require-
where
ments of clause 6.
A0 is the equivalent absorption area, in square metres;
V is the volume of the receiving room, in cubic metres.
5 TEST ARRANGEMENT
3.4 apparent sound reduction index, apparent transmission
For the test arrangement to be used in the field, it is not
loss : Ten times the common logarithm of the ratio of the
possible to standardize the area of the test specimen and
sound power W, incident on a partition under test to the
the volume and shape of the rooms.
total sound power W3 transmitted into the receiving room.
This quantity is denoted by R’ :
Measurements between empty rooms with equal dimensions
should preferably be made with diffusers in each room. If
-
diffusing elements are used, they should be sufficiently
(5)
isolated from the building, for example by placing them on
pads of resilient material.
In general, the sound power transmitted into the receiving
room consists of the sum of the following components :
W,d which has entered the partition directly and is
6 TEST PROCEDURE AND EVALUATION
radiated from it directly;
WDf which has entered the partition directly but is 6.1 Generation of sound field in the source room
radiated from flanking constructions;
The sound generated in the source room should be steady
WFd which has entered flanking constructions and is
and have a continuous spectrum in the frequency range
radiated from the partition directly;
considered. Filters with a bandwidth of at least one-third
octave may be used.
W,, which has entered flanking constructions and is
radiated from flanking constructions;
If the sound source contains more than one loudspeaker
operating simultaneously, the loudspeakers should be con-
Wleak which has been transmitted (as airborne sound)
through leaks, ventilation ducts, etc. tained in one enclosure, the maximum dimension of which
should not exceed 0.7 m. The loudspeakers should be
Under the assumption of diffuse sound fields in the two
driven in phase.
rooms, the apparent sound reduction index may be evalu-
give a sound
ated from the form
...

SLOVENSKI STANDARD
SIST ISO 140-4:1997
01-april-1997
$NXVWLND0HUMHQMH]YRþQHL]ROLUQRVWLY]JUDGEDKLQ]YRþQHL]ROLUQRVWLJUDGEHQLK
HOHPHQWRYGHO7HUHQVNDPHUMHQMDL]ROLUQRVWLPHGSURVWRULSUHG]YRNRPY]UDNX
Acoustics -- Measurement of sound insulation in buildings and of building elements --
Part 4: Field measurements of airborne sound insulation between rooms
Acoustique -- Mesurage de l'isolation acoustique des immeubles et des éléments de
construction -- Partie 4: Mesurage sur place de l'isolation aux bruits aériens entre les
pièces
Ta slovenski standard je istoveten z: ISO 140-4:1978
ICS:
17.140.01 $NXVWLþQDPHUMHQMDLQ Acoustic measurements and
EODåHQMHKUXSDQDVSORãQR noise abatement in general
91.060.01 Stavbni elementi na splošno Elements of buildings in
general
91.120.20 $NXVWLNDYVWDYEDK=YRþQD Acoustics in building. Sound
L]RODFLMD insulation
SIST ISO 140-4:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST ISO 140-4:1997

---------------------- Page: 2 ----------------------

SIST ISO 140-4:1997
INTERNATIONAL STANDARD 140 I IV
~~ ~~~~ ~~
INTERNATIONAL ORGANIZATION FOR STANDARDlZATION*MEWYHAPOLlHAR OPrAHH3AUMR no CTAHAAPTH3AUIIH.ORGANlSATlON INTERNATIONALE DE NORMALISATION
L
Acoustics - Measurement of sound insulation in buildings
and of building elements -
Part IV : Field measurements of airborne sound insulation
between rooms
Acoustique - Mesurage de l'isolation acoustique des immeubles et des 6ltfments de construction -
Partie IV : Mesurage sur place de l'isolation aux bruits atfriens entre les pitkes
First edition - 1978-07-15
U DC 534.833.522.4.08 Ref. No. IS0 140/1\1-1978 (E)
Descriptors : acoustics, acoustic measurement, acoustic insulation, buildings, structural members, rooms, tests, testing conditions, field
tests, airborne sound.
Price based on 5 pages

---------------------- Page: 3 ----------------------

SIST ISO 140-4:1997
FOREWORD
IS0 (the International Organization for Standardization) is a worldwide federation
of national standards institutes (IS0 member bodies). The work of developing
International Standards is carried out through IS0 technical committees. Every
member body interested in a subject for which a technical committee has been set
up 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.
Draft International Standards adopted by the technical committees are circulated
to the member bodies for approval before their acceptance as International
Standards by the IS0 Council.
International Standard IS0 140/IV was developed by Technical Committee
ISO/TC 43, Acoustics, and was circulated to the member bodies in May 1976.
It has been approved by the member bodies of the following countries
Australia India Romania
Austria Israel South Africa, Rep. of
Belgium Italy Sweden
Canada Japan Switzerland
Korea, Rep. of
Czechoslovakia Turkey
Denmark Mexico United Kingdom
Finland
Netherlands U.S.A.
France New Zealand U.S.S. R.
Germany Norway
Hungary Poland
The member body of the following country expressed disapproval of the document
on technical grounds :
Spain
This International Standard, together with International Standards IS0 140/1, III,
VI and VII, cancel and replace IS0 Recommendation R 140-1960, of which they
constitute a technical revision.
Annexes B and C are integral parts of this International Standard.
O International Organization for Standardization, 1978 O
Printed in Switzerland

---------------------- Page: 4 ----------------------

SIST ISO 140-4:1997
INTERNATIONAL STANDARD IS0 140/1V-1978 (E)
Acoustics - Measurement of sound insulation in buildings
and of building elements -
Part IV : Field measurements of airborne sound insulation
between rooms
O INTRODUCTION
IS0 14O/V, Acoustics - Measurement of sound insulation
in buildings and of building elements - Part V : Field
The purpose of this International Standard is
measurements of airborne sound insulation of facade
elements and facades.
- to give procedures to measure the sound insulation
L
between two rooms in buildings, thus making it possible
ISO/R 354, Measurement of absorption coefficients in a
to check whether the desired acoustical conditions have
reverberation room.
been obtained;
ISOIR 71 7, Rating of sound insulation for dwellings.
- to give field procedures to determine whether
building elements have met specifications and to check I EC Publication 225, Octave, half-octave and third-octave
whether faults have occurred during construction. band filters intended for the analysis of sound and vi-
brations.
1 SCOPE AND FIELD OF APPLICATION
This International Standard specifies field methods for
3 DEFINITIONS
measuring the airborne sound insulation properties of
3.1 average sound pressure level in a room : Ten times the
interior walls, floors and doors between two rooms under
common logarithm of the ratio of the space and time
diffuse sound field conditions in both rooms and for deter-
average of the sound pressure squared to the square of the
mining the protection afforded to the occupants of the
reference sound pressure, the space average being taken
building.
over the entire room with the exception of those parts
The results obtained can be used to compare sound insu-
where the direct radiation of a sound source or the near
lation between rooms and to compare actual sound in-
field of the boundaries (wall, etc.) is of significant influence.
sulation with specified requirements.
This quantity is denoted by L :
When determining the protection afforded to the occupants
L
of the building, the standardized level difference (see 3.3) L = 1019 p; +p; +. . .
dB
(1)
is appropriate.
When determining the sound insulation properties of a
where
building element, the apparent sound reduction index
(see 3.4) is used.
p,, p2, . . .,pn are the r.m.s. sound pressures at n
different positions in the room;
NOTES
1 Laboratory measurements of airborne sound insulation of build-
po = 20 pPa is the reference sound pressure.
IS0 140/111.
ing elements are dealt with in
2 Field measurements of airborne sound insulation of facade
3.2 level difference : The difference in the space and time
IS0 140/V.
elements and facades are dealt with in
average sound pressure levels produced in two rooms by
one or more sound sources in one of them. This quantity
is denoted by D :
2 REFERENCES
D= Ll - L2 . . . (2)
IS0 140/11, Acoustics - Measurement of sound insulation
in buildings and of building elements - Part II : Statement
where
of precision requirements.
L1 is the average sound pressure level in the source
IS0 14011 I I, Acoustics - Measurement of sound insulation
room;
in buildings and of building elements - Part III : Labor-
atory measurements of airborne sound insulation of build-
L2 is the average sound pressure level in the receiving
ts.
ing elemen room.
1

---------------------- Page: 5 ----------------------

SIST ISO 140-4:1997
IS0 140/1\/-1978 (E)
3.3 standardized level difference : The level difference where
corresponding to a reference value of the reverberation time
S is the area of the test specimen;
is denoted by DnT :
in the receiving room. This quantity
A is the equivalent absorption area in the receiving
T
I
D,, = D + 10 lg ~d0 room.
(3)
‘O
In the case of evaluation of R’ of a door S is the area of the
where
free opening in which the door including the frame is
mounted. It must be proved that the sound transmission
D is the level difference;
through the rest of the surrounding wall is negligible.
T is the reverberation time in the receiving room;
In the case of staggered rooms, S is that part of the area of
the partition common to both rooms; if, however, the
To is the reference reverberation time.
common area is less than 10m2, the value of S for in-
For dwellings, To is given by
sertion in equation (6) shall be 10 m2 but the measurement
results shall not be used for comparison with results
To = 0,5 s . . . (4)
obtained by measurement in laboratory.
NOTES
NOTE - In the apparent sound reduction index, the sound power
1 The standardizing of the level difference to a reverberation time
is related to the sound power
transmitted into the receiving room
-
of 0.5s takes into account that in dwellings with furniture the
incident on the common partition irrespective of actual conditions
reverberation time has been found - nearly independently of
of transmission.
the volume and of frequency - to be equal to 0.5 s. With this
The apparent sound reduction index is independent of the measur-
standardizing, D,, is dependent on the direction of the sound
transmission if the two rooms have different volumes, ing direction between the rooms if the sound fields are diffuse in
both rooms.
2 The standardizing of the level difference to the reverberation
time in the receiving room of To = 0.5 s is equivalent to standard-
izing the level difference with respect to an equivalent absorption
area of :
4 EQUIPMENT
Ag = 0.32 V
The equipment shall be suitable for meeting the require-
where
ments of clause 6.
A0 is the equivalent absorption area, in square metres;
V is the volume of the receiving room, in cubic metres.
5 TEST ARRANGEMENT
3.4 apparent sound reduction index, apparent transmission
For the test arrangement to be used in the field, it is not
loss : Ten times the common logarithm of the ratio of the
possible to standardize the area of the test specimen and
sound power W, incident on a partition under test to the
the volume and shape of the rooms.
total sound power W3 transmitted into the receiving room.
This quantity is denoted by R’ :
Measurements between empty rooms with equal dimensions
should preferably be made with diffusers in each room. If
-
diffusing elements are used, they should be sufficiently
(5)
isolated from the building, for example by placing them on
pads of resilient material.
In general, the sound power transmitted into the receiving
room consists of the sum of the following components :
W,d which has entered the partition directly and is
6 TEST PROCEDURE AND EVALUATION
radiated from it directly;
WDf which has entered the partition directly but is 6.1 Generation of sound field in the source room
radiated from flanking constructions;
The sound generated in the source room should be steady
WFd which has entered flanking constructions and is
and have a continuous spectrum in the frequency range
radiated from the partition directly;
considered. Filters with a bandwidth of at least one-third
octave m
...

140 I IV
NORME INTERNATIONALE
INTERNATIONAL ORGANIZATION FOR STANDARDIZATlON.ME~YHAPO~HAR OPrAHM3AUMR Il0 CTAH~APTkl3AUMMWRGANlSATlON INTERNATIONALE DE NORMALISATION
Acoustique - Mesurage de l'isolation acoustique des
immeubles et des élhments de construction -
Partie IV : Mesurage sur place de l'isolation aux bruits aériens
entre les pièces
Acoustics - Measurement of sound insulation in buildings and of building elements -
Part IV : Field measurements of airborne sound insulation between rooms
Première édition - 1978-07-15
LL
-
Co
CDU 534.833.522.4.08 RBf. no : IS0 140/1\1-1978 (FI
PI
z
Descripteurs : acoustique, mesurage acoustique, isolation acoustique, bâtiment, élément de construction, piece d'habitation, essai, condi-
.
tions d'essai, essai en place, bruit aérien.
Prix basé sur 5 pages

---------------------- Page: 1 ----------------------
AVANT-PROPOS
L‘ISO (Organisation internationale de normalisation) est une fédération mondiale
d‘organismes nationaux de normalisation (comités membres de I’ISO). L’elaboration
des Normes internationales est confiée aux comités techniques de I‘ISO. Chaque
comité membre intéressé par une étude a le droit de faire partie du comité technique
correspondant. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec I’ISO, participent également aux travaux.
Les projets de Normes internationales adoptés par les comités techniques sont
soumis aux comites membres pour approbation, avant leur acceptation comme
Normes internationales par le Conseil de I‘ISO.
La Norme internationale IS0 140/IV a été élaborée par le comité technique
ISO/TC 43, Acoustique, et a été soumise aux comités membres en mai 1976.
:
Les comités membres des pays suivants l‘ont approuvée
Afrique du Sud, Rép. d’ Hongrie Roumanie
Allemagne Inde Royaume-Uni
Australie Israël Suède
Autriche Italie Suisse
Belgique Japon Tchécoslovaquie
Canada Mexique Turquie
Corée, Rép. de Norvège U.R.S.S.
Danemark Nouvel le-Zélande U.S.A.
Finlande Pays-Bas
Y
France Pologne
Le comité membre du pays suivant l’a désapprouvée pour des raisons techniques :
Espagne
Cette Norme internationale, conjointement avec les Normes internationales
IS0 140/1, I I I, VI et VI I, annule et remplace la Recommandation ISO/R 140-1960
dont elle constitue une révision technique.
Les annexes B et C font partie intégrante de la présente Norme internationale.
-1 Organisation internationale de normalisation, 1978
Imprime en Suisse

---------------------- Page: 2 ----------------------
NORME INTERNATIONALE IS0 140/1V-1978 (F)
Acoustique - Mesurage de l'isolation acoustique des
immeubles et des Mments de construction -
Partie IV : Mesurage sur place de l'isolation aux bruits aériens
entre les pièces
O INTRODUCTION IS0 140/V, Acoustique - Mesurage de l'isolation acous-
tique des immeubles et des éléments de construction -
Le but de la présente Norme internationale est :
Partie V : Mesurage sur place de l'isolation aux bruits
aériens des éléments de facade et des façades.
- de donner des méthodes de mesurage de l'isolation
aux bruits aériens entre deux pièces dans les immeubles,
I SOIR 354, Mesure des coefficients d'absorption en salle
L
de manière qu'il soit possible de contrôler si les condi-
réverbéran te.
tions acoustiques désirées ont été obtenues;
ISOIR 71 7, Évaluation de l'isolement acoustique des habi-
- de donner des méthodes applicables sur place pour
tations.
les éléments de construction sont confor-
déterminer si
Publication CE1 225, Filtres de bandes d'octave, de demi-
mes aux spécifications et contrôler si des erreurs se sont
octave et de tiers d'octave destinés à l'analyse des bruits et
produites au cours de la construction.
des vibrations.
1 OBJET ET DOMAINE D'APPLICATION
3 DÉFINITIONS
La présente Norme internationale spécifie les méthodes
3.1 niveau moyen de pression acoustique dans une pièce :
les propriétés d'isolation
applicables sur place pour mesurer
aux bruits aériens des murs intérieurs, des plafonds et des Dix fois le logarithme décimal du rapport de la moyenne
portes entre deux pièces, placées dans des conditions de spatio-temporelle des carrés des pressions acoustiques au
champ diffus, et pour déterminer la protection apportée carré de la pression acoustique de référence, la moyenne
aux occupants de l'immeuble. spatiale étant prise dans l'étendue de la pièce, à l'exception
des zones OÙ le rayonnement direct de la source et le champ
Les résultats obtenus peuvent être utilisés pour comparer
proche des parois ont une influence notable. Cette grandeur
l'isolation acoustique entre les pièces et pour comparer
est désignée par L et est donnée par la formule :
l'isolation acoustique réelle avec les valeurs spécifiées.
Lors de la détermination de la protection apportée aux L= 1019 p; +p; +. . .
dB . . . (1)
occupants de l'immeuble, on utilise la différence des
niveaux normalisés (voir 3.3).
où
Lors de la détermination des propriétés d'isolation d'un
élément de construction, on utilise l'indice d'affaiblisse-
p1, p2, . . ., pn sont les pressions acoustiques efficaces
ment acoustique apparent (voir 3.4).
relevées en n points différents de la pièce;
NOTES
est la pression acoustique de référence.
Po = 20 WPa
1 Les mesurages en laboratoire de l'isolation aux bruits aériens
des éléments de construction font l'objet de I'ISO 140/111.
3.2 isolation acoustique brute : Différence des moyennes
2 Les mesurages sur place de l'isolation aux bruits aériens des
spatio-temporelles des niveaux de pression acoustique pro-
elements de façade et des façades font l'objet de I'ISO 140/V.
duits dans les deux salles par une ou plusieurs sources de
bruit situées dans l'une d'elles. Cette grandeur est désignée
par D et est donnée par la formule :
2 RÉFÉRENCES
D= Ll - L, . . . (2)
IS0 14011 I, Acoustique - Mesurage de l'isolation acous-
-
tique des immeubles et des éléments de construction
où
Partie II : Spécifications relatives à la fidélité.
est le niveau moyen de pression acoustique dans la
L1
IS0 14011 I I, Acoustique - Mesurage de l'isolation acous-
salle d'émission;
tique des immeubles et des Bléments de construction -
Partie 111 : Mesurage en laboratoire de l'isolation aux bruits
L2 est le niveau moyen de pression acoustique dans la
aériens des éléments de construction.
salle de réception.
1

---------------------- Page: 3 ----------------------
IS0 140/1\/-1978 (F)
3.3 isolation acoustique normalisée : Isolation acoustique Ob
brute correspondant à une valeur de référence de la durée
S est l‘aire de I’éprouvette;
de réverbération de la salle de réception. Cette grandeur est
désignée par O,, et est donnée par la formule :
A est l‘aire d’absorption équivalente de la salle de
réception.
T
-O+ 10lg-dB . . . (3)
’nT -
Dans le cas de I’évaluation de R‘ pour une porte, S est l’aire
TO
de l‘ouverture dans laquelle la porte, y compris son bâti, est
où
montée. On doit démontrer que la transmission à travers les
autres parties du mur voisin est négligeable.
D est l’isolation acoustique brute;
T est la durée de réverbération de la salle de réception; Dans le cas de pièces contiguës et décalées, S est l‘aire de la
portion de cloison commune aux deux pièces; si, toutefois,
To est la durée de réverbération de référence.
cette aire commune est inférieure a 10 m*, la valeur de S
Pour les habitations, To est donné par : à introduire dans I‘équation (6) est 10 m2, mais les résul-
tats du mesurage ne doivent pas être utilisés pour des
To = 0,5 s . . . (4)
comparaisons avec des résultats obtenus par des mesurages
en laboratoire.
NOTES
1 La normalisation de l’isolation acoustique brute par rapport à
NOTE - Dans l‘indice d’affaiblissement acoustique, la puissance
une durée de réverbération de 0,5 s tient compte du fait que, pour
transmise dans la salle de réception dépend de la puissance incidente
les habitations meublées, on a trouvé que la durée de réverbération sur la cloison commune, indépendamment des conditions réelles de
est, presque indépendamment du volume, égale à 0,5 s pour toutes
transmission.
DnT dépend de la direc-
les fréquences. Avec cette normalisation,
L’indice d‘affaiblissement acoustique est indépendant de la direction
tion du son transmis si les deux pièces ont des volumes différents.
de mesurage entre les deux pièces, si les champs sont diffus dans les
2 La normalisation de l‘isolation acoustique brute par rapport à
deux Dièces.
une durée de réverbération de la salle de réception égale a TO = 0.5 s
est équivalente a la normalisation de l’isolation acoustique brute par
rapport à une aire d‘absorption équivalente de :
4 APPAREILLAGE
Ag = 0.32 V
L’appareillage doit permettre de respecter les spécifications
où
du chapitre 6.
Ag est l‘aire d‘absorption équivalente, en mètres carrés;
V est le volume de la salle de réception, en mètres cubes.
5 DISPOSITIONS POUR L‘ESSAI
3.4 indice d’affaiblissement acoustique apparent : Dix fois
Pour les essais sur place, il n‘est pas possible de normaliser
le logarithme décimal du rapport de la puissance acoustique
l’aire de I‘éprouvette ni le volume et la forme des pièces.
W, incidente sur la cloison en essai à la puissance acous-
tique totale W3 transmise dans la salle de réception. Cette Les mesurages réalisés entre des pièces vides, d’égales
grandeur est désignée par R’ et est donnée par la formule : dimensions, devraient être effectués de préférence avec
des diffuseurs dans chaque pièce. Si l’on utilise des élé-
ments diffusants, ceux-ci doivent être suffisamment isolés
(5)
de la construction, par exemple en les plaçant sur des
tam pons éI ast i q u es.
En général, la puissance transmise dans la salle de réception
esî la somme des éléments suivants :
6 MODE OPÉRATOIRE ET ÉVALUATION
W,, puissance reçue directement par la cloison et
rayonnée directement par celle-ci;
6.1 Production du champ acoustique dans la salle
d‘émission
WDr puissance reçue directement par la cloison et
rayonnée par tous les éléments de construction voisins;
Le bruit produit dans la salle d’émission doit être stable et
WFd puissance reçue par les éléments de construction
avoir un spectre continu dans l’étendue des fréquences
voisins et rayonnée directement par la cloison;
considérées. On peut utiliser des filtres avec une largeur de
bande d’au moins un tiers d’octave.
WFf puissance reçue par les Cléments de construction
et rayonnée par ceux-ci;
voisins
Si la source de bruit est constituée de plusieurs haut-parleurs
fonctionnant simultanément, ils doivent être installés dans
W1 puissance transmise (sous forme de bruits aériens)
une seule enceinte; la dimension maximale de celle-ci ne
par des fuites, des conduits de ventilation, etc.
doit pas dépasser 0.7 m. Les haut-parleurs doivent fonction-
En supposant que les champs sont diffus dans les deux
ner en phase.
pièces, l’indice d’affaiblissement acoustique apparent peut
L‘enceinte doit être placée de manière à ce qu‘elle donne
être évalué à partir de :
un champ aussi diffus que possible et à une distance telle
3
de I’éprouvette que le rayonnement direct sur celle-ci ne
R‘= L, - L, + 10 lg -dB .
...