SIST EN ISO 11819-1:2002

SLOVENSKI STANDARD
SIST EN ISO 11819-1:2002
01-september-2002
Acoustics - Measurement of the influence of road surfaces on traffic noise - Part 1:
Statistical Pass-By method (ISO 11819-1:1997)
Acoustics - Measurement of the influence of road surfaces on traffic noise - Part 1:
Statistical Pass-By method (ISO 11819-1:1997)
Akustik - Messung des Einflusses von Straßenoberflächen auf Verkehrsgeräusche - Teil
1: Statistisches Vorbeifahrtverfahren (ISO 11819-1:1997)
Acoustique - Mesurage de l'influence des revetements chaussées sur le bruit émis par la
circulation - Partie 1: Méthode statistique au passage (ISO 11819-1:1997)
Ta slovenski standard je istoveten z: EN ISO 11819-1:2001
ICS:
17.140.30 Emisija hrupa transportnih Noise emitted by means of
sredstev transport
93.080.20 Materiali za gradnjo cest Road construction materials
SIST EN ISO 11819-1:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 11819-1:2002

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SIST EN ISO 11819-1:2002
EUROPEAN STANDARD
EN ISO 11819-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2001
ICS 17.140.30
English version
Acoustics - Measurement of the influence of road surfaces on
traffic noise - Part 1: Statistical Pass-By method (ISO 11819-
1:1997)
Acoustique - Mesurage de l'influence des revêtements Akustik - Messung des Einflusses von Straßenoberflächen
chaussées sur le bruit émis par la circulation - Partie 1: auf Verkehrsgeräusche - Teil 1: Statistisches
Méthode statistique au passage (ISO 11819-1:1997) Vorbeifahrtverfahrtverfahren (ISO 11819-1:1997)
This European Standard was approved by CEN on 11 June 2001.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11819-1:2001 E
worldwide for CEN national Members.

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SIST EN ISO 11819-1:2002
EN ISO 11819-1:2001 (E)
Foreword
The text of the International Standard from Technical Committee ISO/TC 43 "Acoustics" of the
International Organization for Standardization (ISO) has been taken over as an European
Standard by Technical Committee CEN/TC 227 "Road materials", the secretariat of which is held
by DIN.
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 February 2002, and conflicting national
standards shall be withdrawn at the latest by February 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.
NOTE FROM CMC The foreword is susceptible to be amended on reception of the German language
version. The confirmed or amended foreword, and when appropriate, the normative annex ZA for the
references to international publications with their relevant European publications will be circulated with the
German version.
Endorsement notice
The text of the International Standard ISO 11819-1:1997 has been approved by CEN as a
European Standard without any modification.
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SIST EN ISO 11819-1:2002
INTERNATIONAL
IS0
STANDARD
11819-I
First edition
1997-09-l 5
Acoustics -
Measurement of the influence
of road surfaces on traffic noise -
Part 1:
Statistical Pass-By method
Acoustique - Mesurage de /‘influence des rev&tements de chaus&es sur
le bruit 4mis par la circulation -
Partie 1: Mgthode statistique au passage
Reference number
IS0 118194:1997(E)

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SIST EN ISO 11819-1:2002
IS0 11819=1:1997(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 118194 was prepared by Technical Committee
ISOmC 43, Acoustics, Subcommittee SC 1, Noise.
IS0 11819 consists of the following parts, under the general title
Acoustics - Measurement of the influence of road surfaces on traffic
noise:
- Part I: Statistical Pass-By method
- Part 2: Close-proximity method
Annexes A to F of this part of IS0 11819 are for information only.
0 IS0 1997
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
Internet central @ iso.ch
x.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii

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SIST EN ISO 11819-1:2002
ISO11819-1:1997( E)
Introduction
The emission and propagation of road traffic noise greatly depend on road surface characteristics,
notably on texture and porosity. Both these characteristics influence the generation of tyre/road noise
and, in addition, the porosity can influence the propagation of sound, particularly when the propagation
takes place close to the surface. Power unit noise, which is usually generated at a greater height
above the road surface than tyre/road noise, may also be affected during propagation by the porosity
characteristics of the road surface. These effects lead to differences in sound levels, associated with a
given traffic flow and composition, from different road surfaces of up to 15 dB, which can have a
substantial impact on the environmental quality alongside a road.
It is therefore important to be able to measure this influence by a standardized method and to arrive at
a quantitative ranking of road surfaces with respect to traffic noise. This part of IS0 11819 offers such
a method, the objective of which is to satisfy a need expressed by road planners, road administrators,
contractors, manufacturers of so-called “low-noise surfaces” and by other parties concerned with the
prediction and control of road traffic noise.

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SIST EN ISO 11819-1:2002
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SIST EN ISO 11819-1:2002
INTERNATIONAL STANDARD @ Iso IS0 118194 : 1997(E)
- Measurement of the influence of road surfaces on
Acoustics
traffic noise -
Part 1:
Statistical Pass-By method
1
Scope
This part of IS0 11819 describes a method of comparing traffic noise on different road surfaces for
various compositions of road traffic for the purpose of evaluating different road surface: types. Sound
levels representing either light or heavy vehicles at selected speeds are assigned to a certain road
surface. The method is applicable to traffic travelling at constant speed, i.e. free-flowingconditions at
posted speeds of 50 km/h and upwards. For other driving conditions where traffic is not free-flowing,
such as at junctions and where the traffic is congested, the road surface is of less importance.
A standard method for comparing noise characteristics of road surfaces gives road and,,environment
authorities a tool for establishing common practices or limits as to the use of surfacings meeting
certain noise criteria. However, it is not within the scope of IS0 11819 to suggest such criteria.
The Statistical Pass-By (SPB) method is intended to be used essentially for two main purposes. First it
may be used to classify surfaces in typical and good condition as a type according to their influence on
traffic noise (surface classification) and, secondly, it may be used to evaluate the influence on traffic
noise of different surfaces at particular sites irrespective of condition and age. This ,tatter type of
application may be useful for example where a road is to be resurfaced and “before” and “after”
measurements are required in order to assess the differences in traffic noise followingresurfacing.
generally be used for approval of works at any given site.
Clause 4 gives a general description of the SPB method.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions
of this part of IS0 11819. At the time of publication, the editions indicated were valid. All standards are
subject to revision, and parties to agreements based on this part of IS0 11819 are encouraged to
investigate the possibility of applying the most recent editions of the standards indicated below.
Members of IEC and IS0 maintain registers of currently valid International Standards.
IS0 10844:1994, Acoustics - Test surface for road vehicle noise measurement.
Characterization of pavement texture using surface profiles - Part
IS0 13473-l :1997, Acoustics -
1: Determination of mean profile depth.
IEC 60651: 1979, Sound /eve/ meters.
I EC 60942: 1988, Sound calibrators.
I EC 61260: 1995, Hectroacoustics - Octave-band and fractional-octave-band filters.
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SIST EN ISO 11819-1:2002
IS0 118194 :1997(E)
3 Definitions
For the purposes of this part of IS0 11819, the following definitions apply.
Traffic noise, vehicle noise, tyrekoad noise and power unit noise
3.1
3.1 .l traffic noise
overall noise emitted by the traffic running on the road under study
3.1.2 vehicle noise
total noise from an individual vehicle, the two major components of which are power unit noise (3.1.4)
and tyre/road noise (3.1.3)
3.1.3 tyre/road noise
noise generated by the tyre/road interaction
3.1.4 power unit noise
noise generated by the vehicle engine, exhaust system, air intake, fans, transmission, etc.
Statistical Pass-By (SPB) method
3.2
measurement procedure designed to evaluate vehicle and traffic noise generated on different sections
of road surface under specific traffic conditions
NOTE - The measurements are taken from a great number of vehicles operating normally on the road. Results
obtained using this procedure are normalized to standard speeds according to the category or type of road
being considered.
3.3 Road speed categories
Three categories of roads are defined with respect to the range of speeds at which the traffic flows
and these are usually associated with certain areas (urban, suburban, rural, etc.).
3.3.1 “low” road speed category
conditions which relate to traffic operating at an average speed of 45 km/h to 64 km/h
NOTE - These conditions are usually associated with urban traffic.
3.3.2 “medium” road speed category
conditions which relate to traffic operating at an average speed of 65 km/h to 99 km/h
NOTE - These conditions are mostly found in suburban areas or on rural highways.
3.3.3 “‘high” road speed category
conditions which relate to cars operating at an average speed of 100 km/h or more; heavy vehicles
may operate at lower average speed due to speed restrictions
NOTE - These conditions are usually associated with motorway traffic in rural or suburban areas.
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SIST EN ISO 11819-1:2002
IS0 11819-l : 1997(E)
3.4 Vehicle categories
A vehicle category consists of vehicles which have certain common features easy to identify in the
traffic stream, such as the number of axles and the size. The common (features are assumed to
correspond to similarities in their sound emission when driven under the same operating conditions.
The following vehicle categories are considered to be sufficient for Tdescription of the noise
characteristics of road surfaces and are used in this part of IS0 11819 (see-also annex A).
3.4.1 Category No. 1 - cars
passenger cars excluding other light vehicles
3.4.2 Category No. 2 - heavy vehicles
all trucks, buses and coaches with at least two axles and more than four wheels
NOTE - This category consists of Categories 2a and 2b together.
3.4.2.1 Category No. 2a - dual-axle heavy vehicles
trucks, buses and coaches with two axles and more than four wheels
3.4.2.2 Category No. 2b - multi-axle heavy vehicles
trucks, buses and coaches with more than two axles
35 . maximum sound level
highest sound pressure level recorded by the measuring instrument during1.a vehicle pass-by, using
the appropriate frequency weighting and time weighting F, for vehicles which are acoustically
identifiable, i.e. are not significantly disturbed by other vehicles (see also 7.2)
Vehicle Sound Level, Lveh
3.6
maximum A-weighted sound pressure level determined at a reference speed:from a regression line of
the maximum A-weighted sound pressure level versus the logarithm of speed, calculated for each
vehicle category
Statistical Pass-By Index (SPBI)
3.7
noise index for comparison of road surfaces, that is based on the Vehicle Sound Levels and takes into
account the mix and speeds of vehicles
38 . reference surface
surface selected according to the purpose of the measurement, following certain rules listed in this
part of IS0 11819; levels on the reference surface are normalized to zero level-,(0 dB) and levels on all
other surfaces are presented as differences from this reference level
NOTE - The main purpose of this method is to compare road surfaces with respect1 to traffic noise emission.
Sound levels measured on a certain surface may, therefore, be presented in comparison to sound levels
measured on another surface which is then considered as a reference surface.
39 . absorptive surfaces
1) For road or ground surfaces: surface for which a substantial part of the incident acoustical energy is
absorbed
EXAMPLES - Typical absorptive surfaces are loose gravel, sand, some porous pavements and
ground covered by grass, ivy, or other low-growing vegetation.
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SIST EN ISO 11819-1:2002
IS0 11819-I : 1997(E)
2) For noise barriers: type of surface with which some noise barriers are equipped on the source side
with the intention of reducing sound reflections
4 Measuring principle
In the Statistical Pass-By (SPB) method, the maximum A-weighted sound pressure levels of a
statistically significant number of individual vehicle pass-bys are measured at a specified road-side
location together with the vehicle speeds. Each measured vehicle is classified into one of three vehicle
categories: “cars”, “dual-axle heavy vehicles” and “multi-axle heavy vehicles”. Other vehicle categories
are not used for this evaluation, since they do not provide any additional information regarding road
surface influence.
For each of three speed ranges defined in 3.3, as well as for each of the three vehicle categories, a
nominated reference speed is given. Each individual pass-by level together with its vehicle speed is
recorded, and a regression line of the maximum A-weighted sound pressure level versus the
logarithm of speed is calculated for each vehicle category. From this line, the average maximum A-
weighted sound pressure level is determined at the reference speed. This level is called the Vehicle
Sound Level, Lveh.
For the purpose of reporting the acoustic performance of road surfaces the Vehicle Sound Levels for
cars, dual-axle heavy vehicles and multi-axle heavy vehicles are added on a power basis, assuming
certain proportions of these vehicle categories, to give a single “index” which constitutes the final
result. This index is called the Statistical Pass-By Index (SPBI) and can be used for comparison of
road surfaces so that their influence on sound level of a mixed traffic flow can be determined. It is not
suitable for determining actual traffic noise levels.
5 Measuring instruments
. Sound level instrumentation
51
The sound level meter (or the equivalent measuring system) shall meet the requirements of a Type 1
instrument according to IEC 60651.
A windscreen shall be used and should be of a type specified by the microphone manufacturer as
suitable for the particular microphone. It should be ascertained from the manufacturer that the
windscreen does not detectably influence the performance of the sound level meter under the ambient
conditions of the test.
Frequency analysis instrumentation
5.2
Frequency analysis of the measured sound using one-third-octave band resolution is recommended,
but not mandatory. The frequency range of 50 Hz to 10 000 Hz (centre frequencies of one-third-octave
bands) shall be covered. The one-third-octave-band filters shall conform to IEC 61260.
5.3 Calibration
At the beginning of the measurements, and following any warm-up time specified by the manufacturer,
the overall sensitivity of the sound level meter or the equivalent measuring system (including the
microphone) shall be checked. If necessary, it shall be adjusted according to the manufacturer’s
instructions. This may require use of a sound calibrator. These checks shall be repeated at the end
of the measurements and the values obtained recorded. Any deviations shall be recorded in the test
report. If the calibration readings on the sound level meter differ by more than 0,5 dB during a series
of measurements, the test shall be considered invalid. The same procedure shall be followed if a
frequency analyser is used.

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SIST EN ISO 11819-1:2002
IS0 11819-I :I 997(E)
The sound calibrator device shall meet the requirements of IEC 60942, Class0 or Class 1.
The compliance of the sound calibrator with the requirements of the appropriate class of IEC 60942
shall be verified annually. The compliance of the sound level meter, or equivalent measuring system,
with the requirements of IEC 60651 shall be verified at least every two yearsLThis shall be performed
by a laboratory accredited or otherwise authorized to perform calibrations traceable to the national
standards.
5.4 Vehicle speed measurement instrumentation
The vehicle speed at the instant when the vehicle passes the microphoneshall be measured with a
standard uncertainty of less than =t 3%. Measuring devices which rest on the road surface and are
activated by the passage of vehicle tyres should not be used.
5.5 Temperature measurement instrumentation
The temperature measuring instrument(s) shall have a maximum permiss,ibte error of 1 OC. Meters
using an infrared technique shall not be used for air temperature measurements.
6 Test sites
61 . Selection of measuring site
The following considerations apply for site selection.
Each road test section shall extend at least 30 m on both sides from the: microphone location. For
a)
the “high” road speed category this distance is increased to 50 m.
b) The road shall be essentially level and straight. Roads with slight bends or with gradient < 1 %
may be considered as valid test sites for the purposes of this part of ISO:lJl 819.
c) The number of vehicles judged to be moving at constant speed shall ibe sufficient in order to
allow a reasonable total measuring time.
The requirements on background noise at the test site according to clause 12 shall be observed.
4
See also 7.2 regarding selection of vehicles.
e) The road surface should be in a good condition, unless the intention ,is to study the effect of
condition, and be homogeneous over the entire test section. Road surfaces which exhibit
unusually high unevenness characteristics, surface cracking, bitumen bleeding, excessive stone
loss or contain expansion joints, for example, would not normally be considered as suitable for
surface classification purposes.
The traffic flowing on the road section of interest should contain sufficient numbers of each
f )
category of vehicle to enable a full analysis of each vehicle category to be carried out.
road surfaces change their noise characteristics rather quickly after opening for
NOTE - Since some types of
laid surfaces have limited validity.
traffic, measurements on newly
6.2 Paired and single site measurements
Measurements described in this part of IS0 11819 will commonly be taken at a single test surface and
then compared with similar measurements taken at other surfaces where traffic may be different.
However, in some cases, the noise characteristics of different surfaces can be compared by taking
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SIST EN ISO 11819-1:2002
IS0 11819-I : 1997(E)
@ IS0
simultaneous measurements on two or more road sections where the surfaces to be compared have
been laid in adjacent road sections. These are referred to as ‘paired’ measurements since the
measurement technique employs the selection of the same vehicles from the traffic stream as they
pass each measurement site.
The use of this technique will improve the accuracy of the comparison due to the elimination of
differences in traffic composition and climate.
From 6.1 it follows that the measurement locations will need to be separated along the road by at least
60 m (100 m for the “high” road speed category).
paired sites, for exa .mple due to se lection specified in 7.2, shall also
Vehicles excluded from one of the
site.
be excluded from the other paired
6.3 Deviations from free-field conditions
For surface classification purposes, the measurement microphone should be located in the acoustical
free field. In practice, this means that acoustic reflections from surfaces such as building facades,
noise barriers, road cuttings and embankments shall be at least 10 dB lower than the direct sound to
be measured. As a guideline, 25 m of space around the microphone free of any reflecting objects
other than the ground is usually adequate to ensure that approximate free field conditions exist.
6.4 Considerations of guard rails and other barriers which may reflect or screen the sound
There shall be no large reflecfing surfaces, such as solid safety barriers or embankments, within
10 m of a line drawn from the measuring microphone position, crossing the roadway perpendicular to
the line of travel. This is precisely shown as a rectangle in figure la). If safety barriers are present
within the rectangle, they shall be covered with effective sound absorbing material prior to the
measurements. The presence of such surfaces and the type of covering shall be duly stated in the
report.
It is necessary to temporarily remove a short section of any safety barrier or guard rail located in front
of the measurement microphone to ensure that minimal screening from the obstacles occurs at the
measurement location. Within the part of the rectangle shown in figure la) which is between the road
and a line parallel to the road and which goes through the microphone position, there shall be no
potentially screening roadside barrier or guard rail.
Protective fences will not normally affect the results and can be ignored for the purpose of site and
microphone position selection. Treatments on some noise barriers with the intention to reduce sound
reflections are not sufficiently absorptive to allow such barriers within the rectangle shown in figure
.
Ia)
NOTE 1 In IS0 11819, a solid safety barrier is a concrete wall structure designed to prevent vehicles from
leaving the road or crossing the median.
NOTE 2 In IS0 11819, a guard rail is a structure consisting of a metal beam or plate attached to rigid posts and
designed to prevent vehicles from leaving the road or crossing the median. There is also a type of guard rail
consisting of stretched steel wires attached to rigid posts.
NOTE 3 In IS0 11819, a protective fence is a structure fabricated of wire or cable (usually chain link) mounted
on support posts and intended to prevent animals or human beings of entering the road.

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SIST EN ISO 11819-1:2002
IS0 11819-l :1997(E)
median marking
--.-.l.“-L.l----l-lIL
centre of test lane
-------.~.~.~I-
No reflecting solid safety barrier allowed within this rectangle
unless covered with sound absorptive material. No screening
rail or safety barrier allowed within the part of this rectangle
which is between the microphone position and the test lane
(darker shaded part)
a)
road-side area
Area with arbitrary covering;
grass or plants shall not be tall;
depressions shall be covered.
Microphone position
Min. area covered with material
having sound absorption similar
No requirements
to that of tested surface.
in this area.
b)
- Requirements regarding freedom from reflecting or screening safety barriers or
Figure 1
guard rails (upper part, Fig. la) and regarding the minimum coverage with
acoustically appropriate surface between the test lane and the microphone (lower
part, Fig. 1 b)
(Figure not to scale)
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SIST EN ISO 11819-1:2002
IS0 11819-l :1997(E)
6.5 Surface between the tested road surface and microphone
Ideally, the surface between the microphone position and the edge of the test lane should be covered
with the same material as the road surface in the measuring lane. However, at some sites it may not
be possible to achieve this condition. When measurements are being made for surface classification
purposes, it is necessary to ensure that at least half of the area between the centre of the test lane
and the microphone shall have acoustical properties similar to the surface under test, and be
essentially level with the road surface. See figure lb). This may be accomplished by placing an
appropriate covering material over non-conforming surfaces. The selection of this material is left to the
judgement of the person responsible for the measurement. Figure 1 b) shows the angles over which
the covering should be applied. If this practice is undertaken, full details shall be summarized in the
report.
The 3,75 m nearest the microphone may be grass or another surface with significant absorption. Any
vegetation in this area shall be kept as short as possible.
Any roadside ditch or other significant depression shall be at least 5 m from the centre of the test lane.
When these propagation conditions cannot be met, the site is not suitable for acoustical classification
measurements (note, however, the possibility specified in 8.1 and figure 3 of using a microphone on
the other side of the road in cases where it is difficult to meet the requirements with the “normal”
microphone position).
6.6 Special site conditions
In cases where the intention is to investigate the effect of a modification or other change in the road
surface, it may be desirable to make a “before/after” study. In such studies it is not necessary to meet
all the site requirements, as long as it can be ascertained that there are no changes of importance for
sound emission, propagation or reflections from the “before” until the “after” situations. One shall then
observe that significant changes in vegetation from season to season might have an influence.
Such special studies shall be duly identified as being “special” in the measuring protocol and any site
conditions at variance with the specifications given in 6.1 to 6.5 shall be reported.
Traffic conditions
7.1 Vehicle classification
Only vehicles which clearly fall within any of the categories described in 3.4 shall be measured. Where
there is any doubt in classifying a vehicle, the measurement for that vehicle shall be discarded from
the study.
A more detailed vehicle classification is optional. See annex A for the categories that should be used
in such cases.
7.2 Selection of vehicles for measurement
Measurements shall only be taken on individual vehicle pass-bys which can be clearly distinguished
acoustically from other traffic on the road. The following criteria shall be used to judge if a vehicle
pass-by is distinguishable.
a) Just p
...