SIST EN ISO 12001:2009

SLOVENSKI STANDARD
SIST EN ISO 12001:2009
01-november-2009
1DGRPHãþD
SIST EN ISO 12001:1999
SIST EN ISO 12001:1999/AC:1999
Akustika - Emisija hrupa naprav in opreme - Pravila za oblikovanje in pripravo
pravil za merjenje hrupa (ISO 12001:1996)
Acoustics - Noise emitted by machinery and equipment - Rules for the drafting and
presentation of a noise test code (ISO 12001:1996)
Akustik - Geräuschabstrahlung von Maschinen und Geräten - Regeln für die Erstellung
und Gestaltung einer Geräuschmeßnorm (ISO 12001:1996)
Acoustique - Bruit émis par les machines et équipements - Règles pour la préparation et
la présentation d'un code d'essai acoustique (ISO 12001:1996)
Ta slovenski standard je istoveten z: EN ISO 12001:2009
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
SIST EN ISO 12001:2009 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 12001:2009

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SIST EN ISO 12001:2009
EUROPEAN STANDARD
EN ISO 12001
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2009
ICS 17.140.20 Supersedes EN ISO 12001:1996
English Version
Acoustics - Noise emitted by machinery and equipment - Rules
for the drafting and presentation of a noise test code (ISO
12001:1996)
Acoustique - Bruit émis par les machines et équipements - Akustik - Geräuschabstrahlung von Maschinen und
Règles pour la préparation et la présentation d'un code Geräten - Regeln für die Erstellung und Gestaltung einer
d'essai acoustique (ISO 12001:1996) Geräuschmeßnorm (ISO 12001:1996)
This European Standard was approved by CEN on 3 August 2009.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12001:2009: E
worldwide for CEN national Members.

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SIST EN ISO 12001:2009
EN ISO 12001:2009 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 12001:2009
EN ISO 12001:2009 (E)
Foreword
The text of ISO 12001:1996 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 12001:2009 by
Technical Committee CEN/TC 211 “Acoustics” the secretariat of which is held by DS.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by January 2010, and conflicting national standards shall be withdrawn at
the latest by January 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 12001:1996.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 12001:1996 has been approved by CEN as a EN ISO 12001:2009 without any modification.

3

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SIST EN ISO 12001:2009

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SIST EN ISO 12001:2009
IS0
INTERNATIONAL
12001
STANDARD
First edition
1996-l 2-l 5
- Noise emitted by machinery
Acoustics
and equipment - Rules for the drafting
and presentation of a noise test code
Acoustique - Bruits 6mis par /es machines et Bquipements - R&g/es
pour la prgpara tion et la p&en ta tion d ‘un code d ’essai acous tique
Reference number
IS0 12001 :I 996(E)

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SIST EN ISO 12001:2009
IS0 12001:1996(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 12001 was prepared by Technical Committee
lSO/TC 43, Acoustics, Subcommittee SC 1, Noise.
This first edition of IS0 12001 replaces parts of IS0 2204.
part of this International Standard. An-
Annexes A and B form an integral
nexes C and D are for i nfo rmation only.
0 IS0 1996
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-1211 Geneve 20 l Switzerland
Printed in Switzerland

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SIST EN ISO 12001:2009
0 IS0
IS0 12001:1996(E)
Introduction
In the determination, declaration and verification of noise emission values
for specific types of machinery and equipment, standardized noise test
codes are required for many purposes.
Several basic International Standards dealing with the noise emitted by
machinery and equipment exist. In order to prepare a noise test code for
a specific family of machinery or equipment, it is necessary to select the
most appropriate basic documents and to establish additional require-
ments for that family (e.g. installation and mounting conditions, operating
conditions, measurement positions, noise declarations, information to be
recorded and reported, etc.).
A noise test code is a standard for a specific family, sub-family or type of
machinery or equipment. Such a code gives all the information necessary
to carry out as efficiently as possible the determination, declaration and
verification of the noise emission characteristics of the machine under
test. This International Standard specifies what information is necessary
for the preparation of noise test codes.

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SIST EN ISO 12001:2009
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SIST EN ISO 12001:2009
INTERNATIONAL STANDARD 0 IS0 IS0 12001:1996(E)
Acoustics - Noise emitted by machinery and
equipment - Rules for the drafting and presentation
of a noise test code
- are in full accordance with basic standards on
1 Scope
measurement, declaration and verification of noise
emissions; and
- reflect the latest technical knowledge of methods
This International Standard specifies the technical re-
of determining the noise emissions from the
quirements of a noise test code for a specific family
specific family of machinery or equipment under
of machinery or equipment. It is primarily applicable
consideration.
to stationary machinery and equipment, including
hand-held tools, as well as those that present hazards
due to mobility or load lifting.
NOTE 1 Annex A lists the basic International Standards
to be used in the drafting of a noise test code. An outline
of a typical noise test code summarizing the information
The purpose of a noise test code is to permit com-
that is required is given in annex B. Noise emission quan-
parable test results to be obtained on the noise
tities are described in annex C.
emissions of machines from the same family, thus
enabling users to make comparisons and to check the
declared noise emission data. The quantities de-
2 Normative references
scribed in a noise test code are also useful for noise
specifications in private contracts, for planning and for
The following standards contain provisions which,
noise reduction purposes. through reference in this text, constitute provisions
of this International Standard. At the time of publica-
Specific test codes for various types of machinery and tion, the editions indicated were valid. All standards
equipment are established and used in accordance
are subject to revision, and parties to agreements
with the requirements of basic International Stan-
based on this International Standard are encouraged
dards. Standardized noise test codes give detailed re-
to investigate the possibility of applying the most re-
quirements on mounting, loading and operating cent editions of the standards indicated below.
conditions for the particular family to which the ma- Members of IEC and IS0 maintain registers of cur-
chinery under test belongs, as well as the location of rently valid International Standards.
a work station(s) and other specified positions (if any).
IS0 3740:1980, Acoustics - Determination of sound
power levels of noise sources - Guidelines for the
The purpose of this International Standard is to assist
use of basic standards and for the preparation of noise
technical standardization committees responsible for
specific families of machinery or equipment in pre- test codes.
paring noise test codes to ensure that such noise test
IS0 3741: -l), Acoustics - Determination of sound
codes
power levels of noise sources using sound
pressure - Precision methods for reverberation
- are as homogeneous as possible, with each indi-
rooms.
vidual test code having the same basic structure;
I) To be published. (Revision of IS0 3741:1988 and IS0 37421988)

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SIST EN ISO 12001:2009
IS0 12001:1996(E) 0 IS0
IS0 3743-l :I 994, Acoustics - Determination of sound pressure levels at a work station and at other
sound power levels of noise sources - Engineering specified positions - Survey me thod in situ.
methods for small, movable sources in reverberant
IS0 11203:1995, Acoustics - Noise emitted by ma-
fields - Part I: Comparison method for hard-walled
chinery and equipment - Determination of emission
test rooms.
sound pressure levels at a work station and at other
IS0 3743-2:1994, Acoustics - Determination of specified positions from the sound power level.
sound power levels of noise sources using sound
IS0 11204: 1995, Acoustics - Noise emitted by ma-
pressure - Engineering methods for small, movable
chinery and equipment - Measurement of emission
sources in reverberant fields - Part 2: Methods for
sound pressure levels at a work station and at other
special reverberation test rooms.
specified positions - Method requinng environmental
IS0 3744: 1994, Acoustics - Determination of sound corrections.
power levels of noise sources using sound pressure
IEC 651 :I 979, Sound level meters, and Amend-
- Engineering method in an essentially free field over
ment 1: 1993.
a reflecting plane.
I EC 804: 1985, Integrating-averaging sound level
IS0 3745: 1977, Acoustics - Determination of sound
meters, and Amendment I:1989 and Amend-
power levels of noise sources - Precision methods
ment 2: 1993.
for anechoic and semi-anechoic rooms.
I EC 1043: 1993, Electroacoustics - Instruments for
- Determination of sound
IS0 3746: 1995, Acoustics
the measurement of sound intensity - Measurement
power levels of noise sources using sound pressure
with pairs of pressure sensing microphones.
- Survey method using an enveloping measurement
surface over a reflecting plane.
I EC 1260: 1995, Electroacoustics - Octave-band and
fractional-octave-band filters.
IS0 3747: 1987, Acoustics - Determination of sound
power levels of noise sources - Survey method us-
ing a reference sound source.
3 Definitions
IS0 4871: 1996, Acoustics - Declaration and verifi-
For the purposes of this International Standard, the
cation of noise emission values of machinery and
following definitions apply.
equlpmen t.
3.1 basic noise emission standard (B-type stan-
IS0 9614-I :I 993, Acoustics - Determination of
dard): Standard which specifies the procedure for
sound power levels of noise sources using sound in-
determining the noise emission of machinery and
tensity - Part I: Measurement at discrete points.
equipment in such a way as to obtain reliable, repro-
ducible results with a specified degree of accuracy.
IS0 9614-2:1996, Acoustics - Determination of
sound power levels of noise sources using sound in-
3.2 noise test code (C-type standard): A standard
tensity - Part 2: Measurement by scanning.
that is applicable to a particular class, family or type
of machinery or equipment, which specifies all the
IS0 11200:1995, Acoustics - Noise emitted by ma-
information necessary to carry out efficiently the de-
chinery and equipment - Guidelines for the use of
termination, declaration and verification of the noise
basic standards for the determination of emission
emission characteristics under standardized con-
sound pressure levels at a work station and at other
ditions.
specified positions.
3.3 emission: Airborne sound radiated by a well-
IS0 11201 :I 995, Acoustics - Noise emitted by ma-
defined noise source (e.g. the machine under test)
chinery and equipment - Measurement of emission
under specified operating and mounting conditions.
sound pressure levels at a work station and at other
specified positions - Engineering method in an es-
NOTE 2 Emission values may be incorporated in a prod-
uct label and/or product specification. The basic noise
sentially free field over a reflecting plane.
emission quantities are the sound power level of the source
itself and the emission sound pressure levels at a work
IS0 11202:1995, Acoustics - Noise emitted by ma-
station and/or at other specified positions (if any) in the
chinery and equipment - Measurement of emission
vicinity of the source.

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SIST EN ISO 12001:2009
63 IS0 IS0 12001:1996(E)
5 Equation (1) is identical to that for the familiar IS0 envi-
3.4 emission sound pressure, p: The sound press-
ronmental noise descriptor “equivalent continuous sound
ure, at a specified position near a noise source, when
pressure level” defined in IS0 1996-l. However, the emis-
the source is in operation under specified operating
sion quantity defined above is used to characterize the noise
and mounting conditions on a reflecting plane surface,
emitted by a machine under test and assumes that stan-
excluding the effects of background noise and of re-
dardized measurement and operating conditions as well as
flections other than those from the plane or planes
a controlled acoustical environment are used for the
permitted for the purpose of the test. It is expressed
measurements.
in pascals.
3.7 sound power, W: The rate per unit time at
which airborne sound energy is radiated by a source.
3.5 emission sound pressure level, LI,: Ten times
It is expressed in watts.
the logarithm to the base 10 of the ratio of the square
of the emission sound pressure, p ’lt), to the square
3.8 sound power level, L,: Ten times the logarithm
of the reference sound pressure, pi, measured with
to the base 10 of the ratio of the sound power radi-
a particular time weighting and a particular frequency
ated by the source under test to the reference sound
weighting, selected from those defined in IEC 651. It
power. It is expressed in decibels.
is expressed in decibels. The reference sound press-
ure is 20 PPa.
The frequency weighting or the width of the fre-
quency band used shall be indicated. The reference
NOTE 3 Examples include:
power is 1 pW (IO- ‘* W).
- maximum A-weighted emission sound pressure level
NOTE 6 For example, the A-weighted sound power level
with time weighting F: L,,*rmax;
is &*.
sound pressure level:
- C-weighted peak emission
The sound power level shall be determined in ac-
L
pC,peak-
cordance with either a test code for a specific family
of machinery or equipment or, if no test code exists,
The emission sound pressure level shall be deter-
a method that complies with one of the standards
mined at a specified position and in accordance with
selected from IS0 3741 to IS0 3747, inclusive, or
either a test code for a specific family of machines or,
with parts 1 or 2 of IS0 9614.
if no test code exists, a method that complies with
the IS0 11200 series.
3.9 noise emission value: A general term by which
any one or more of the A-weighted sound power
level, Lu/A, or the A-weighted time-averaged emission
3.6 time-averaged emission sound pressure
sound pressure level, LpA, or the C-weighted peak
level, Lpeqr: Emission sound pressure level of a con-
emission sound pressure level, Lpc peak, is inferred.
I
tinuous steady sound that, within a measurement
time interval, T, has the same mean square sound
3.10 measured noise emission value, L: The A-
pressure as a sound under consideration which varies
weighted sound power level, or the A-weighted
with time. It is expressed in decibels.
time-averaged emission sound pressure level, or the
C-weighted peak emission sound pressure level, as
It is given by the following equation:
determined from measurements. Measured values
T * may be determined either from a single machine or
P (0
. . .
L 10 Ig dt dB
peqT = from the average of a number of machines, and are
2
T J
O PO
not rounded.
A-weighted time-averaged emission sound pressure
3.11 noise emission declaration: Information on
levels are denoted by LpAeqT, which is usually abbrevi-
the noise emitted by the machine, given by the
ated to LpA. LpAeqT shall be measured with an instru-
manufacturer or supplier in technical documents or
ment which complies with the requirements of
other literature concerning noise emission values. The
IEC 804.
noise emission declaration may take the form of ei-
ther the declared single-number noise emission value
NOTES
or the declared dual-number noise emission value.
4 In general, the subscripts “eq” and ‘IT” are omitted
3.12 uncertainty, K: Value, in decibels, of the
since time-averaged emission sound pressure levels are
measurement uncertainty associated with a meas-
necessarily determined over a certain measurement time
ured noise emission value.
interval.

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SIST EN ISO 12001:2009
0 IS0
IS0 12001:1996(E)
Guidance on appropriate values for K is given in
NOTE 7
3.19.1 fluctuating noise: A noise whose level
annex A of IS0 4871:1996.
varies continuously and to an appreciable extent dur-
ing the period of observation. See figure 1 b).
3.13 declared single-number noise emission
value, Ld: The sum of a measured noise emission
3.19.2 intermittent noise: A noise whose level ab-
value and the associated uncertainty factor, rounded
ruptly drops to the level of the background noise
to the nearest decibel:
several times during the period of observation. The
time during which the level remains at a constant
L,=L+K
value different from that of the ambient is of the order
of 1 s or more. See figure 1 c).
NOTE 8 IS0 9296 requires that the declared A-weighted
sound power level, bAdI of computers and business equip-
3.19.3 impulsive noise: A noise consisting of a se-
ment be expressed in bels using the identity 1 B = 10 dB,
ries of bursts of sound energy, each burst having a
rounded to the nearest 0,l 9.
duration of less than approximately 1 s.
3.14 declared dual-number noise emission value,
3.19.3.1 isolated burst of sound energy: A single
L and K: A measured noise emission value, L, and its
burst of sound energy or a series of bursts with in-
associated uncertainty K, both rounded to the nearest
tervals larger than 0,2 s between the individual bursts.
decibel.
See figure 1 d).
NOTE 9 If a specific noise test code requires that the
mean emission sound pressure level from a number of
3.19.3.2 quasi-impulsive noise: A series of noise
specified positions be declared, it is denoted by LpAm.
bursts of comparable amplitude with intervals shorter
than 0,2 s between the individual bursts. See
3.15 work station; operator ’s position: A position
figure 1 e).
in the vicinity of the machine under test which is in-
tended for the operator.
3.20 broad-band noise: Noise in which the acous-
tical energy is distributed over a relatively wide range
3.16 operator: An individual whose work station is
of frequencies.
in the vicinity of a machine and who is performing a
work task associated with that machine.
NOTES
12 The spectrum is generally smooth and continuous, al-
3.17 specified position: A position defined in re-
though it may vary significantly from “flat ”. If the broad-
lation to a machine, including, but not limited to, an
band sound does not contain any significant discrete tones,
operator ’s position. The position can be a single, fixed
the sound will lack a subjective quality of pitch or tonality.
point, or a combination of points along a path or on a
surface located at a specified distance from the ma-
13 Examples of broad-band sounds without discrete tones
chine, as described in the relevant noise test code, if
are the sound of a waterfall, the noise from an air diffuser
any.
outlet in a typical room, and the noise from a highway.
NOTES
3.21 narrow-band noise: Noise in which the
acoustical energy is concentrated in a relatively nar-
10 Positions located in the vicinity of a work station, or in
row range of frequencies.
the vicinity of an unattended machine, may be identified as
“bystander positions ”.
NOTES
11 The following definitions are of a general nature. Ref-
14 The spectrum will generally show a localized “hump”
erence should be made to specific standards of the
or peak in amplitude. Narrow-band sound may be superim-
IS0 3740 series and the IS0 11200 series for more detailed
posed on broad-band sound. If the narrow-band sound does
definitions.
not contain any significant discrete tones, the sound will
generally lack a subjective quality of pitch or tonality.
3.18 steady noise: A noise with negligibly small
fluctuations of level within the period of observation.
15 Examples of narrow-band sounds without discrete
See figure 1 a).
tones are the sound of distant thunder (low frequency), the
sound of wind gusting over a prairie or through a canyon
3.19 non-steady noise: A noise whose level shifts
(mid frequency), and the sound of an air leak in an
significantly during the period of observation. automobile tyre (high frequency).

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SIST EN ISO 12001:2009
IS0 12001:1996(E)
Time
Time
b) Fluctuating noise
a) Steady noise
n-n- ,”
Time Time
Time
e) Quasi-impulsive noise
c) Intermittent noise d) Isolated burst of sound energy
Figure 1 - Pictorial examples of various types of noise
3.25 essentially free field over a reflecting plane:
discrete tone: A periodic sound pressure vari-
A sound field in the half space above a plane surface
ation that gives rise to the sensation of pitch.
on which the machine under test is located that is
NOTES
disturbed to only a small degree by reflections.
16 A discrete tone can be either a purely sinusoidal vari-
ation (sometimes called a “pure tone ”), in which case the
frequency spectrum would show a single “spike” at the
3.26 in situ sound field: A sound field in the half
sinusoidal frequency, or, more typically, a non-sinusoidal
space above a plane surface on which the machine
variation, in which case the spectrum would show a spike
under test is located that may be disturbed by many
at the fundamental frequency and other spikes at harmonics
reflections.
of the fundamental.
17 Examples of discrete tones are the hum of a fan, a
beep from a digital gadget, and a note played on a musical
3.27 direct sound field: That portion of the sound
instrument.
field in a test room over which the sound received
directly from the source predominates.
3.23 free field: A sound field in a homogeneous,
isotropic medium free of boundaries. In practice, it is
a field in which reflections at the boundaries are neg- 3.28 reverberant sound field: That portion of the
ligible over the frequency range of interest. sound field in a test room over which the influence
of sound received directly from the source is negli-
gible.
3.24 free field over a reflecting plane (hemi-free
sound field): A sound field in a homogeneous,
isotropic medium in the half space above an infinite,
3.29 semi-reverberant sound field: That portion of
rigid plane surface on which the machine under test
the sound field in a test room where neither the
is located.
sound received directly from the source nor the
reverberant sound dominates.

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SIST EN ISO 12001:2009
IS0 12001:1996(E) 0 IS0
classes (grades 1 through 3). International Standards of the
3.30 hemispherically divergent sound field: The
IS0 11200 series for the measurement of emission sound
sound field of an omnidirectional source which is
pressure levels at a work station and at other specified
situated near a hard reflecting plane (usually the
positions include methods representing two of the three
ground) but free from other obstructions.
classes (grades 2 and 3). See table A.2
4 Classification of different types of
5.1 Survey grade (grade 3)
noise
This method requires the least amount of time and
The character of a noise may be described by its fre- equipment. It may be used for comparison between
noise sources with similar characteristics. The sound
quency spectrum and by variations in the level of the
field in the vicinity of the source is described by the
noise with time.
readings of a sound level meter or sound intensity
Many noises have a continuous spectrum; i.e. the
meter. A limited number of measurement points is
sound energy is evenly distributed over a major por-
used and no detailed analysis of the acoustic envi-
tion of the audible frequency range. In some cases,
ronment is made. The measurements are made in situ
discrete tones may be clearly audible in the noise.
with little effort expended to control the acoustic en-
vironment in which the source or sources operate.
Noises which display different dependencies upon
The time dependence of the noise is noted.
time include: noise, non-steady noise, fluctuating
noise, intermittent noise, impulsive noise, quasi-
Readings of the sound level or the sound intensity
steady impulsive noise and an isolated burst of sound
shall be obtained with instrumentation which com-
energy.
plies with the requirements of IEC 651, IEC 804 or
IEC 1043.
Classification of the accuracy grade of
5
The survey method is generally of limited value if
measurement methods corrective measures to reduce the noise of the
source(s) are to be evaluated. The use of class 2
Each of the basic standards of the IS0 3740 and instrumentation in accordance with IEC 651 or
IS0 9614 series for the determination of sound power IEC 1043 is acceptable.
levels of noise sources includes a table of standard
deviations of reproducibility. A grade 1 method pro-
5.2 Engineering grade (grade 2)
vides the highest precision and a grade 3 method
provides the lowest.
In this method, noise emission determinations are
made with a particular time weighting and a particular
The basic standards of the IS0 11200 series, de-
frequency weighting and/or by noise emission
scribing methods of measuring the emission sound
measurements in octave, one-third-octave or nar-
pressure levels at a work station and at other speci-
rower frequency bands, from which the A-weighted
fied positions (if any), do not include tables of
values may be calculated. The acoustic environment
measurement uncertainty values. Where required,
is analysed to determine its effect upon the
such values shall be determined by tests carried out
measu
...