SIST EN ISO 11204:1997
(Main)Acoustics - Noise emitted by machinery and equipment - Measurement of emission sound pressure levels at a work station and at other specified positions - Method requiring environmental corrections (ISO 11204:1995)
Acoustics - Noise emitted by machinery and equipment - Measurement of emission sound pressure levels at a work station and at other specified positions - Method requiring environmental corrections (ISO 11204:1995)
This standard prescribes a method for measuring the emission sound pressure levels at work stations and other specified positions in the vicinity of different types of machinery and equipment. The standard prescribes requirements on the test environment. The purpose of the measurements is to permit comparison of the performance of different units of a given family of machinery or equipment, under defined environmental conditions and standardized mounting and operating conditions. The data obtained are also used for the declaration and verif. of emission sound pressure levels as spec. in ISO 4871.
Akustik - Geräuschabstrahlung von Maschinen und Geräten - Messung von Emissions-Schalldruckpegeln am Arbeitsplatz und an anderen festgelegten Orten - Verfahren mit Umgebungskorrekturen (ISO 11204:1995)
Acoustique - Bruit émis par les machines et équipements - Mesurage des niveaux de pression acoustique d'émission au poste de travail et en d'autres positions spécifiées - Méthode nécessitant des corrections d'environnement (ISO 11204:1995)
L'IEC 60695-10-3:2016 spécifie un essai de déformation par réduction des contraintes de moulage. Elle est applicable aux matériels électrotechniques, y compris les parties composées de matériaux polymères. Cette méthode d'essai est destinée à évaluer les effets provoqués par la réduction des contraintes résiduelles induites par traitement, se produisant dans un assemblage polymère moulé d'un produit final. Cette réduction de contraintes se produit lorsque l'échantillon (sous ou hors tension) est exposé au conditionnement à une température définie pendant une période de temps définie. L'éprouvette d'essai est considérée comme ayant satisfait à l'essai si, après le conditionnement à température ambiante, elle satisfait aux critères d'essai définis. La présente publication fondamentale de sécurité est essentiellement destinée à être utilisée par les comités d'études dans le cadre de l'élaboration de normes conformément aux principes établis dans le Guide IEC 104 et le Guide ISO/IEC 51. Elle n'est pas destinée à être utilisée par les fabricants ou les organismes de certification. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- Références mises à jour;
- Matériel mis à jour;
- Termes et définitions ajoutés;
- et Bibliographie ajoutée.
Mots-clés: Risques du feu, Chaleur anormale, l'ingénierie de la sécurité incendie, déformation par réduction des contraintes de moulage
Akustika - Emisija hrupa naprav in opreme - Merjenje emisijske ravni zvočnega tlaka na mestu delovanja in na drugih opredeljenih mestih - Metoda z upoštevanjem popravkov zaradi okolja (ISO 11204:1995)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 11204:1997
01-april-1997
$NXVWLND(PLVLMDKUXSDQDSUDYLQRSUHPH0HUMHQMHHPLVLMVNHUDYQL]YRþQHJD
WODNDQDPHVWXGHORYDQMDLQQDGUXJLKRSUHGHOMHQLKPHVWLK0HWRGD]
XSRãWHYDQMHPSRSUDYNRY]DUDGLRNROMD ,62
Acoustics - Noise emitted by machinery and equipment - Measurement of emission
sound pressure levels at a work station and at other specified positions - Method
requiring environmental corrections (ISO 11204:1995)
Akustik - Geräuschabstrahlung von Maschinen und Geräten - Messung von Emissions-
Schalldruckpegeln am Arbeitsplatz und an anderen festgelegten Orten - Verfahren mit
Umgebungskorrekturen (ISO 11204:1995)
Acoustique - Bruit émis par les machines et équipements - Mesurage des niveaux de
pression acoustique d'émission au poste de travail et en d'autres positions spécifiées -
Méthode nécessitant des corrections d'environnement (ISO 11204:1995)
Ta slovenski standard je istoveten z: EN ISO 11204:1995
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
SIST EN ISO 11204:1997 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
INTERNATIONAL
Is0
STANDARD 11204
First edition
1995-I 2-l 5
Acoustics - Noise emitted by machinery
and equipment - Measurement of
emission sound pressure levels at a work
station and at other specified positions -
Method requiring environmental
corrections
Acoustique - Bruit 6mis par /es machines et gquipements - Mesurage
des niveaux de pression acoustique d ’kmission au poste de travail et en
d ’autres positions spGcifi6es - Mgthode nbessitant des corrections
d ‘environnemen t
Reference number
IS0 11204:1995(E)
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SIST EN ISO 11204:1997
IS0 11204:1995(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). The work
of preparing International Standards is normally carried out through IS0
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. IS0
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard IS0 11204 was prepared by Technical Committee
lSO/TC 43, Acoustics, Subcommittee SC 1, Noise.
Annex A forms an integral part of this International Standard. Annexes B,
C and D are for information only.
.
0 IS0 1995
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 the publisher.
International Organization
for Standardization
Case Postale 56 l CH-121 1 Geneve 20 l Switzer 4and
Printed in Switzerland
ii
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SIST EN ISO 11204:1997
0 IS0 IS0 11204:1995(E)
Introduction
0.1 This International Standard specifies a method for measuring the
emission sound pressure levels at a work station and at other specified
positions in the vicinity of a machine or piece of equipment. The method
specified in this International Standard follows the method specified in
IS0 11201 (engineering method), except for the following:
measurements are permitted in situ; and
a)
b) a method is specified for determining a local environmental correction
which yields results approximating those obtained in a free field over
a reflecting plane. This correction is used to derive the emission sound
pressure levels at specified positions, including work stations. If this
correction is less than the specified value, the results meet the engi-
neering grade of accuracy, but otherwise they meet the survey grade.
0.2 This International Standard is one of a series (IS0 11200 to
IS0 11204) which specifies various methods for determining the noise
emissions of a piece of machinery or equipment, or a sub-assembly of
such equipment (machine under test). IS0 11200 gives guidance on the
choice of the method to be used to determine the emission sound
pressure levels of machinery and equipment. It also gives details of Inter-
national Standards giving methods for the determination of sound power
levels.
III
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SIST EN ISO 11204:1997
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SIST EN ISO 11204:1997
IS0 11204:1995(E)
INTERNATIONAL STANDARD 0 IS0
Acoustics - Noise emitted by machinery and
Measurement of emission sound
equipment -
pressure levels at a work station and at other specified
- Method requiring environmental
positions
corrections
fied positions may be located in the vicinity of an
1 Scope
attended or unattended machine. Such positions are
sometimes referred to as bystander positions.
1.1 General
This International Standard specifies requirements on
the test environment. Instructions are given for the
This International Standard specifies a method for
installation and operation of the machine under test
measuring the emission sound pressure levels of
and for the choice of microphone positions for the
machinery and equipment, at a work station and at
work station and for other specified positions. The
other specified positions nearby, in any environment
purpose of the measurements is to permit compar-
which meets certain qualification requirements.
ison of the performance of different units of a given
family of machinery or equipment, under defined en-
Emission sound pressure levels are measured as A-
vironmental conditions and standardized mounting
weighted and, if required, C-weighted peak, and in
and operating conditions. The data obtained may also
frequency bands.
be used for the declaration and verification of emis-
sion sound pressure levels as specified in IS0 4871.
NOTE 1 The contents of this and related International
Standards are summarized in table 1 of IS0 11 ZOO:1 995.
NOTE 2 At any given position in relation to a particular
machine, and for given mounting and operating conditions,
A method is given for determining a local environ-
the emission sound pressure levels determined by the
mental correction (the acceptable maximum value of
method of this International Standard will in general be
which is specified) to be applied to the measured
lower than the directly measured sound pressure levels for
sound pressure levels to exclude the effects of re-
the same machine in the typical workroom where it is used.
flections from reflecting surfaces other than the plane
This is due to reverberation and the contributions of other
on which the machinery or equipment is placed. This
machines. A method of calculating the sound pressure lev-
correction is based upon the mean sound pressure els in the vicinity of a machine operating alone in a
workroom is given in IS0 11690-3. Commonly observed
level on a measurement surface, the sound pressure
differences are 1 dB to 5 dB, but in extreme cases the dif-
level measured at a specified position, and either an
ference may be even greater.
environmental indicator or the equivalent absorption
area of the test room. The grade of accuracy of the
measurements (engineering or survey) depends upon
the vaule of the local environmental correction.
1.2 Types of noise and noise sources
A work station is occupied by an operator. It may be
located in open space in the room where the source The method specified in this International Standard is
operates, or in a cab fixed to the source, or in an en- applicable to all types of machinery, both moving and
closure remote from the source. One or more speci- stationary, for indoor or outdoor use.
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SIST EN ISO 11204:1997
0 IS0
IS0 11204:1995(E)
The method is applicable to machines of all sizes, and
2 Normative references
to all types of noise as defined in IS0 2204 and
IS0 12001. The following standards contain provisions which,
through reference in this text, constitute provisions
of this International Standard. At the time of publi-
1.3 Test environment
cation, the editions indicated were valid. All standards
are subject to revision, and parties to agreements
The method is applicable to an indoor or outdoor en-
based on this International Standard are encouraged
vironment with one or more reflecting planes present,
to investigate the possibility of applying the most re-
meeting specified requirements.
cent editions of the standards indicated below.
Members of IEC and IS0 maintain registers of cur-
rently valid International Standards.
1.4 Specified positions
IS0 2204: 1979, Acoustics - Guide to Inter-national
This International Standard is applicable to work
Standards on the measurement of airborne acoustical
stations and other specified positions where emission
noise and evaluation of its effects on human beings.
sound pressure levels are to be measured.
IS0 3744:1994, Acoustics - Determination of sound
Examples of appropriate positions where measure-
power- levels of noise sources using sound pressure
ments may be made include the following:
- Engineering method in an essentially free field over-
a) work station located in the vicinity of the machine a reflecting plane.
under test; this is the case for many industrial
IS0 3746: 1995, Acoustics - Determination of sound
machines and domestic appliances;
power levels of noise sources using sound pressure
b) work station within a cab which is an integral part - Survey method using an enveloping measurement
of the machine under test; this is the case for surface over a reflecting plane.
many industrial trucks and earth-moving ma-
IS0 11200: 1995, Acoustics - Noise emitted by ma-
chines;
chinery and equipment - Guidelines for the use of
c) work station within a partial or total enclosure (or basic standards for the determina Con of emission
behind a screen) supplied by the manufacturer as sound pressure levels at a work station and at other
specified positions.
an integral part of the machinery or equipment;
d) work station partially or totally enclosed by the IS0 12001: -‘1, Acoustics - Noise emitted by ma-
machine under test; this situation may be en- chinery and equipment - Rules for the drafting and
countered with some large industrial machines; presentation of a noise test code.
e) bystander positions occupied by individuals not EC 651 :I 979, Sound level meter-s.
responsible for the operation of the machine
EC 804: 1985, Integrating-averaging sound level
under test, but who may be in its immediate vi-
ne tefs.
cinity, either occasionally or continuously;
EC 942: 1988, Sound calibrator-s.
f) other specified positions, not necessarily work
stations or bystander positions.
IEC 1260: -2), Electroacoustl ’cs - Octave-band and
The work station may also lie on a specified path fractional-octave-band filters.
along which an operator moves (see 11.4).
3 Definitions
15 . Measurement uncertainty
For the purposes of this International Standard, the
While it is not possible to give universal values for the
following definitions apply. More detailed definitions
standard deviation of reproducibility of emission
may be found in noise test codes for specific types
sound pressure levels at work stations, guidance is
of machinery and equipment.
given in clause 4.
1) To be published.
2) To be published. (Revision of IEC 225:1966)
2
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SIST EN ISO 11204:1997
IS0 11204:1995(E)
0 IS0
3.1 emission: Airborne sound radiated by a well- ated to LpA. LpAeqT shall be measured with an instru-
ment which complies with the requirements of
defined noise source (e.g. the machine under test).
IEC 804.
Noise emission descriptors may be incorporated
NOTE 3
in a product label and/or product specification. The basic NOTES
noise emission descriptors are the sound power level of the
source itself and the emission sound pressure levels at a 5 In general, the subscripts eq and T are omitted since
time-averaged emission sound pressure levels are necess-
work station and/or at other specified positions (if any) in the
arily determined over a certain measurement time interval.
vicinity of the source.
6 Equation (1) is identical to that for the familiar IS0 en-
3.2 emission sound pressure, p: The sound press-
vironmental noise descriptor “equivalent continuous sound
ure, at a specified position near a noise source, when pressure level” defined in IS0 1996-1. However, the emis-
sion quantity defined above is used to characterize the noise
the source is in operation under specified operating
emitted by a machine under test and assumes that stan-
and mounting conditions on a reflecting plane surface,
dardized measurement and operating conditions as well as
excluding the effects of background noise as well as
a controlled acoustical environment are used for the
the effects of reflections other than those from the
measurements.
plane or planes permitted for the purpose of the test.
It is expressed in pascals.
3.3.2 peak emission sound pressure level, L!, peak:
I
The highest instantaneous value of the emission
3.3 emission sound pressure level, Lp: Ten times
sound pressure level determined over an operational
the logarithm to the base IO of the ratio of the square
cycle. It is expressed in decibels.
of the emission sound pressure, p* t), to the square
1
of the reference sound pressure, po, measured with
3.3.3 single-event emission sound pressure level,
a particular time weighting and a particular frequency
L p ,s: Time-integrated emission sound pressure level
weighting, selected from those defined in IEC 651. It
of ’an isolated single sound event of specified duration
is expressed in decibels. The reference sound press-
T (or specified measurement time T) normalized to
ure is 20 PPa.
To=1 s.
NOTE 4 Examples include:
It is expressed in decibels and is given by the follow-
- maximum A-weighted emission sound pressure level ing equation:
with time-weighting F: LpAFmax;
2
P (4
L pls= IO Ig +lT ,dt dB . . .
(2)
emission sound pressure level: I
- C-weighted peak
O O PO
L
pC,peak-
+lOlg 2 dB
= LpeqT
The emission sound pressure level shall be deter-
TO
mined at a specified position in accordance with either
a test code for a specific family of machines or, if no
NOTE 7 The above equation is identical to that for the
test code exists, a method that complies with the
familiar IS0 environmental noise descriptor “sound expo-
sure level ”. However, the emission quantity defined above
IS0 11200 series.
is used to characterize a noise source and assumes that a
controlled environment is used for the measurements.
3.3.1 time-averaged emission sound pressure
level, LpeqT: Emission sound pressure level of a con-
3.4 impulsive noise index (impulsiveness): Quan-
tinuous steady sound that, within a measurement
tity by means of which the noise emitted by a source
time interval, T, has the same mean square sound
can be characterized as “impulsive ”. (See annex C.)
pressure as a sound under consideration which varies
It is expressed in decibels.
with time.
It is expressed in decibels and is given by the follow-
3.5 free field over a reflecting plane: Sound field
ing equation: in a homogeneous, isotropic medium in the half space
above an infinite, rigid plane surface on which the
2
machine under test is located.
P (4
ldt dB . . .
L
(1)
peqT= lo lgGIT
O PO
3.6 work station; operator ’s position: Position in
A-weighted time-averaged emission sound pressure
the vicinity of the machine under test which is in-
levels are denoted by L,,AeqT, which is usually abbrevi- tended for the operator.
3
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SIST EN ISO 11204:1997
0 IS0
IS0 11204:1995(E)
3.16 environmental indicator, K2: A term to ac-
3.7 operator: Individual whose work station is in the
count for the influence of reflected or absorbed sound
vicinity of a machine and who is performing a work
task associated with that machine. on the surface sound pressure level: K2 is frequency
dependent and is expressed in decibels. In the case
of A-weighting, it is denoted KzA (see the IS0 3740
3.8 specified position: Position defined in relation
series).
to a machine, including, but not limited to, an operat-
or’s position. The position can be a single, fixed point,
3.17 local environmental correction, KS: A cor-
or a combination of points along a path or on a surface
rection term to account for the influence of reflected
located at a specified distance from the machine, as
sound on the emission sound pressure level at a
described in the relevant noise test code, if any exists.
specified position (e.g. a work station) for the machine
NOTE 8 Positions located in the vicinity of a work station, under test. K3 is dependent upon both frequency and
or in the vicinity of an unattended machine, may be ident-
position and is expressed in decibels. In the case of
ified as “bystander positions ”.
A-weighting, it is denoted I&.
3.9 operational period: Interval of time during
which a specified process is accomplished by the 4 Measurement uncertainty
machine under test (e.g. for a dishwasher when
washing or rinsing or drying). A single value of an emission sound pressure level of
a noise source determined in accordance with the
method specified in this International Standard is likely
3.10 operational cycle: Specific sequence of oper-
to differ from the true value at a fixed position by an
ational periods occurring while the machine under test
amount within the range of the measurement uncer-
performs a complete work cycle. Each operational
tainty. The uncertainty in measurements of emission
period is associated with a specific process that may
sound pressure levels arises from several factors
occur only once, or may be repeated, during the
which affect the results, some associated with en-
operational cycle (e.g. for a dishwasher when washing
vironmental conditions in the measurement room and
and rinsing and drying).
others with experimental techniques.
3.11 measurement time interval: Portion or a
The measurement uncertainty depends on the stan-
multiple of an operational period or operational cycle
dard deviation of reproducibility and on the degree of
for which the emission sound pressure level is deter-
confidence that is desired. Extensive measurement
mined or over which the maximum emission sound
data are necessary in order to establish standard de-
pressure level is searched for.
viations of reproducibility of emission sound pressure
levels at individual positions and, in any case, these
3.12 time history: Continuous recording of the
standard deviations are likely to vary considerably be-
emission sound pressure level, as a function of time,
tween the many different types of machinery and
which is obtained during one or more operational pe-
equipment to which this International Standard is ap-
riods of an operational cycle.
plicable. It is therefore not possible to provide infor-
mation which is universally applicable, and reference
3.13 background noise: The noise from all sources
can only be made to noise test codes for relevant data
other than the machine under test.
on individual types of noise source.
NOTE 9 Background noise may include contributions
The method described in this International Standard
from airborne sound, structure-borne vibration, and elec-
yields different degrees of accuracy depending upon
trical noise in instrumentation.
the specified position and the related local environ-
mental correction. If I&A is less than or equal to
3.14 background noise level: The sound pressure
2 dB, the degree of accuracy is that of an engineering
level measured when the machine under test is not
method. If KS* is greater than 2 dB, but less than or
operating. It is expressed in decibels.
equal to 7 dB, the degree of accuracy is that of a
survey method. The accuracy is position dependent.
3.15 background noise correction, K,: A correction
term to account for the influence of background noise A value of the standard deviation of reproducibility
on the emission sound pressure level at the specified equal to or less than 2,5 dB (excluding variations in
operating and mounting conditions) for engineering
positions of the machine under test. K, is frequency
dependent and is expressed in decibels. The cor- grade measurements, and equal to or less than 5 dB
rection in the case of A-weighting, I&, is to be de- for survey grade measurements can be expected for
termined from A-weighted measured values. the A-weighted emission sound pressure level of a
4
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SIST EN ISO 11204:1997
IS0 11204:1995(E)
0 IS0
source which emits noise with a relatively “flat” 6.3 Enclosed work station positions
spectrum in the frequency range 100 Hz to
When the operator is located in an enclosed cab or in
IO 000 Hz. The given value for the standard deviation
an enclosure remote from the machine under test, the
of reproducibility is a maximum value, but for a well-
cab or enclosure is regarded as an integral part of the
defined family of machines, it may be smaller. For
machine under test and, consequently, sound re-
example, for one family of woodworking machines, it
flections inside the cab or enclosure are considered
has been shown that the standard deviation of
contributions to the emission sound pressure level.
reproducibility is equal to I,0 dB.
No environmental corrections are permitted.
5 Instrumentation
During noise emission measurements, doors and
windows of the cabin or enclosure shall be open or
The instrumentation system, including the micro-
closed as defined in the noise test code for the ma-
phone and cable, shall meet the requirements for a
chinery or equipment being measured.
class 1 instrument specified in IEC 651 or, in the case
of integrating-averaging sound level meters, in
NOTE 10 Because of the instrumentation and back-
IEC 804.
ground noise level requirements of this International Stan-
dard, the measurements will comply with engineering grade
For measurements in octave or one-third-octave
requirements and accuracy (see IS0 11201).
bands, the filters shall meet the requirements of
IEC 1260.
If the work station or bystander ’s position of the ma-
chine is located inside a cab or a cabin, an additional
Before and after each series of measurements, a
“conventional” work station or bystander ’s position
sound calibrator with an accuracy of + 0,3 dB (class
outside the cab or cabin (e.g. for maintenance) in the
1 as specified in IEC 942) shall be applied to the
vicinity of machine under test shall be specified in the
microphone to verify the calibration of the entire
noise test code.
measuring system at one or more frequencies over
the frequency range of interest.
6.4 Criterion for background noise
The compliance of the calibrator with the require-
ments of IEC 942 shall be verified once a year. The
At the microphone position(s), the background noise
compliance of the instrumentation system with the
(including wind noise at the microphone) measured
of IEC 651 (or, in the case of
requirements
as a weighted sound pressure level or in each of the
integrating-averaging systems, with the requirements
frequency bands of interest shall be at least 6 dB (and
of IEC 804) shall be verified at least every 2 years.
preferably more than 15 dB) below the level due to
the machine under test. Corrections for background
The date of the last verification of the compliance with
noise in decibels are given by the following equation:
the relevant IEC standards shall be recorded.
K, = - IO Ig (1 - 10- “. ‘hL) dB . . .
(3)
6 Test environment
where AL is the difference between the sound
pressure levels measured, at a specified position, with
6.1 General
the machine under test in operation and turned off,
respectively.
Any environment which meets the qualification re-
quirements of 6.2 and which is adequately isolated
For the purposes of this International Standard, if
from background noise in accordance with the re-
AL > 15 dB, assume K, = 0; if AL < 6 dB (i.e.
quirements of 6.4 is suitable for measurements in
K,A > I,3 dB), the measurement is invalid according
accordance with this International Standard.
to this International Standard.
6.2 Criterion for the adequacy of the test
K, shall be determined for each microphone position.
environment
6.5 Ambient conditions during
IS0 3744:1994, annex A, and IS0 3746:1995, annex
A, describe procedures for determining the magnitude measurements
of the environmental indicator KzA, to account for de-
Ambient conditions may have an adverse effect on
viations of the test environment from ideal, free-field
the microphone used for the measurements. Such
conditions. For this International Standard, the en-
vironmental indicator, KzA, shall not exceed 7 dB. conditions (e.g. strong electric or magnetic fields,
5
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SIST EN ISO 11204:1997
@I3 IS0
IS0 11204:1995(E)
Corrections K, and K3 to be considered are those rel-
wind, high or low temperatures, or impingement of
evant to the frequency weighting for which emission
air discharge from the machine under test) shall be
sound pressure levels have been measured. For A-
avoided by proper selection or positioning of the
weighting:
microphone.
L = L ’,, - K,A - &A . . .
(4)
PA
66 l Local environmental correction
where the prime indicates measured values; no prime
Annex A describes a procedure for determining the indicates emission values.
magnitude of the local environmental correction K3, to
For a specified position inside an enclosure, as de-
account for the influence of reflected sound on the
fined in 6.3, no environmental corrections are permit-
emission sound pressure level at the specified
ted.
position(s).
NOTE 13 If the machine under test produces isolated
The method given in annex A requires data for a
single-event sounds,
the single-event emission sound
number of measurement positions around the ma-
pressure level at the specified position (see 3.3.3) L,, ls,
chine under test, as well as information about the
should be determined.
acoustical properties of the test room. Measurements
made in accordance with this International Standard
9 Installation and operation of machine
are valid if &A does not exceed 7 dB. lf &A is less
than or equal to 2 dB, the degree of accuracy is that
under test
of an engineering method. If &A is greater than
2 dB, but less than or equal to 7 dB, the degree of
9.1 General
accuracy is that of a survey method.
The manner in which the machine under test is in-
stalled and operated may have a significant influence
7 Quantities to be measured
on the emission sound pressure levels at the speci-
fied positions. This clause specifies conditions that are
The basic quantities to be measured at each specified
intended to minimize variations in the noise emission
position over the specified operational periods or
due to the installation and operating conditions of the
operational cycle of the machine under test are
machine under test. Relevant instructions of a noise
test code, if any exists for the family of machinery or
- the A-weighted sound pressure level, LtpA (the
equipment to which the machine under test belongs,
prime indicates measured values);
shall be followed. The same installation and operating
conditions of the machine under test shall be used for
- the C-weighted peak sound pressure level,
the determination of emission sound pressure levels
L
pC,peak-
and sound power levels. The noise test code for the
NOTES
machinery concerned shall describe the installation,
mounting and operating conditions in detail.
11 Sound pressure levels using other frequency
weightings or in octave or one-third-octave frequency
NOTE 14 The noise test code may make an exception to
bands, as well as other entities relating to the time-history
this requirement on identical installation, mounting and op-
of the noise emission (impulsiveness, sound pressure level
erating conditions for equipment that is used on tables.
as a function of time, etc.) may also be measured, as re-
Such equipment may be mounted on the floor during sound
quired for the design of low-noise machines.
power determinations.
12 For some. applications, it may not be necessary to
Particularly for large machines, it is necessary to make
measure the value of the C-weighted peak sound pressure
a decision as to which components, sub-assemblies,
level
...
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