1970L0157 — EN — 29.06.1987 — 008.001 — 1
This document is meant purely as a documentation tool and the institutions do not assume any liability for its contents
►B COUNCILDIRECTIVE
of6February1970
ontheapproximationofthelawsoftheMemberStatesrelatingtothepermissiblesoundleveland
theexhaustsystemofmotorvehicles
(70/157/EEC)
(OJ L 42, 23.2.1970, p. 16)
Amended by:
Official Journal
No page date
►M1Commission Directive 73/350/EEC of 7 November 1973 L 321 33 22.11.1973
►M2Council Directive 77/212/EEC of 8 March 1977 L 66 33 12.3.1977
►M3Commission Directive 81/334/EEC of 13 April 1981 L 131 6 18.5.1981
►M4Commission Directive 84/372/EEC of 3 July 1984 L 196 47 26.7.1984
►M5Council directive 84/424/EEC of 3 September 1984 L 238 31 6.9.1984
►M6Council Directive 87/354/EEC of 25 June 1987 L 192 43 11.7.1987
Amended by:
►A1Act of Accession of Denmark, Ireland and the United Kingdom of Great
Britain and Northern IrelandL 73 14 27.3.1972
►A2Act of Accession of Spain and Portugal L 302 23 15.11.1985
▼B
COUNCILDIRECTIVE
of6February1970
on the approximationof the lawsofthe Member States relating to
the permissible sound level and the exhaust system of motor vehi-
cles
(70/157/EEC)
THE COUNCIL OF THE EUROPEAN COMMUNITIES,
Having regard to the Treaty establishing the European Economic
Community, and in particular Article 100 thereof;
Having regard to the proposal from the Commission;Having regard to the Opinion of the European Parliament(
1);
Having regard to the Opinion of the Economic and Social
Committee(2);
Whereas the technical requirements which motor vehicles must satisfy
pursuant to national laws relate, inter alia, to the permissible sound
level and the exhaust system;
Whereasthos e requirementsdiffer from one Member State to another;
whereas it is therefore necessary that all Member States adopt the samerequirements either in addition to or in place of their existing rules, inorder, in particular, to allow the EEC type approval procedure which
wasthe s ubject of the Council Directive(
3) of 6 February 1970 on the
approximation of the lawsof the Member Statesrelating to the typeapproval of motor vehiclesand their trailersto be applied in res pectof each type of vehicle;
HAS ADOPTED THIS DIRECTIVE:
Article 1
For the purposes of this Directive, ‘vehicle’ means any motor vehicle
intended for use on the road, with or without bodywork, having at least
four wheels and a maximum design speed exceeding 25 kilometres perhour, with the exception of vehicleswhich run on rails , agriculturaltractorsand machinery and public worksvehicles .
Article 2
No Member State may, on grounds relating to the permissible sound
level and the exhaust system, refuse to grant EEC or national type-
approval in respect of a type of motor vehicle or type of exhaustsystem or component of such a system regarded as a separate technicalunit,
— if the vehicle satisfies the requirements of Annex I as regards the
sound level and exhaust system,
— if the exhaust system or any component thereof, considered as a
separate technical unit within the meaning of Article 9a of Direc-tive 70/156/EEC satisfies the requirements of Annex II.
Article 2a
1. No Member State may, on grounds relating to the permissible
sound level and the exhaust system, refuse or prohibit the sale, registra-tion, entry into service or use of any vehicle in which the sound leveland the exhaust system satisfy the requirements of Annex I.1970L0157 — EN — 29.06.1987 — 008.001 — 2
(1) OJ No C 160, 18.12.1969, p. 7.
(2) OJ No C 48, 16.4.1969, p. 16.
(3) OJ No L 42, 23.2.1970, p. 1.▼M3
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2. No Member State may, on grounds relating to the permissible
sound level and the exhaust system, prohibit the placing on the marketof an exhaust system or any component thereof considered as a sepa-
rate technical unit within the meaning of Article 9a of Directive 70/
156/EEC if, within the meaning of Article 2, it isof a type in res pectof which a type-approval hasbeen granted.
Article 3
The amendments necessary for adjusting the requirements of the Annex
so as to take account of technical progress, with the exception of therequirementss et out under ►
M3items5.2.2.1 and 5.2.2.5 of Annex
I◄, shall be adopted in accordance with the procedure laid down in
Article 13 of the Council Directive on the type approval of motor vehi-clesand their trailers .
Article 4
1. Member States shall put into force the provisions containing the
requirementsneeded in order to comply with thisDirective withineighteen monthsof itsnotification and s hall forthwith inform theCommission thereof.
2. Member States shall ensure that the texts of the main provisions
of national law which they adopt in the field covered by thisDirective
are communicated to the Commission.
Article 5
This Directive is addressed to the Member States.1970L0157 — EN — 29.06.1987 — 008.001 — 3
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ANNEX I
EEC TYPE-APPROVAL IN RESPECT OF THE SOUNDLEVEL OF A
TYPEOFMOTORVEHICLES
1. DEFINITIONS
1.1. Type of vehicle for the purposes of EEC type-approval as
regardsitssoundlevel
For the purposes of this Directive, ‘type of vehicle’ means
vehicles which do not differ essentially as regards the
following parts:
1.1.1. the shape or materials of the bodywork (particularly the engine
compartment and itss oundproofing);
1.1.2. the length and width of the vehicle;
1.1.3. the type of engine (two- or four-stroke, reciprocating or rotary
piston, number and capacity of cylinders, number and type of
carburettors or injection systems, arrangement of valves, rated
maximum power and corresponding engine speed (S));
1.1.4. the transmission system, particularly the number of gears and
their ratios;
1.1.5. the number, type and arrangement of the exhaust systems;
1.1.6. the number, type and arrangement of the intake systems.
1.2. Exhaustandintakesystems
1.2.1. ‘Exhaust system’ means a complete set of parts necessary to
reduce the noise produced by the vehicle's engine exhaust.
1.2.2. ‘Intake system’ means a complete set of parts necessary to
reduce the noise produced by the vehicle's engine intake.
1.2.3. For the purposes of this Directive, these systems do not include
the manifolds.
1.3. Differenttypesofexhaustorintakesystem
‘Different types of exhaust or intake system’ means systems
characterized by fundamental differences, such as the
following:
1.3.1. systems bearing different trade marks or trade names;
1.3.2. systems in which the characteristics of the materials of a
component differ, or in which the componentsare of different
shape or size; a change in the plating procedure (galvanization,
aluminium coating, etc.) isnot deemed to produce a difference
of type;
1.3.3. systems in which the operating principles of at least one
component differ;
1.3.4. systems in which the components are combined differently.
1.4. Componentofanexhaustorintakesystem
‘Component of an exhaust or intake system’ means one of the
separate components which together form the exhaust system
(e.g. exhaust pipes, the silencer proper) or the intake system
(e.g. air filter).
2. APPLICATION FOR EEC TYPE-APPROVAL
2.1. The application for EEC type-approval in respect of the sound
level of a type of motor vehicle must be submitted by the
manufacturer of the vehicle or hisauthorized repres entative.
2.2. It must be accompanied by the undermentioned documents in
triplicate and the following information:
2.2.1. a description of the type of vehicle with reference to the points
mentioned in item 1.1 above. The numbersand/or s ymbols
identifying the engine type and vehicle type must be indicated;1970L0157 — EN — 29.06.1987 — 008.001 — 4
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2.2.2. a list, with appropriate identification, of the component parts of
the exhaust and intake systems;
2.2.3. a drawing of the entire exhaust system with an indication of its
position on the vehicle;
2.2.4. a detailed drawing of each component so that it can be easily
located and identified, and an indication of the materialsus ed.
2.3. A vehicle representative of the type in respect of which type-
approval is sought must be submitted to the technical service
responsible for the tests by the vehicle manufacturer or his
authorized representative.
2.4. At the request of the technical service, a specimen of the
exhaust system and an engine of at least the same cylinder
capacity and rated maximum power asthat fitted to the vehicle
in respect of which type-approval is sought must also be
submitted.
3. MARKINGS
3.1. The exhaust and intake system components, excluding fixing
hardware and pipes, must bear:
3.1.1. the trade mark or name of the manufacturer of the systems and
their components;
3.1.2. the manufacturer'strade des cription.3.2. These markings must be clearly legible and indelible.
4. EEC TYPE-APPROVAL
4.1. If an application within the meaning of item 2.1 isapproved,
the competent authority will draw up a certificate, corre-
sponding to the type which appears in Annex III, to be
attached to the EEC vehicle type-approval certificate.
5. SPECIFICATIONS
5.1. General specifications
5.1.1. The vehicle, its engine and exhaust and intake systems must be
designed, constructed and mounted such that, under normal
conditions of use and notwithstanding the vibrations to which
they may be subject, the vehicle satisfies the requirements ofthisDirective.
5.1.2. The systems must be designed, constructed and mounted so
that reasonable resistance to the corrosion phenomena to which
they are exposed is obtained having regard to the conditions of
use of the vehicle.
5.2. Specificationsrelatingtosoundlevels
5.2.1. Method of measurement
5.2.1.1. The sound emitted by the type of vehicle submitted for EEC
type-approval must be measured in accordance with each of
the two methods described in item 5.2.2.4 in the case of
moving vehicles and item 5.2.3.4 in the case of stationary vehi-
cles, respectively(
1).
5.2.1.2. The two values measured as specified in item 5.2.1.1, above,
must be recorded in the test report and in a certificate corre-
sponding to the model shown in Annex III.
5.2.2. Sound level of moving vehicles
5.2.2.1. Limit values
The sound level measured in accordance with items 5.2.2.2 to
5.2.2.5 of this Annex shall not exceed the following limits:1970L0157 — EN — 29.06.1987 — 008.001 — 5
(1) A stationary vehicle test is conducted in order to establish a reference value for the
authorities which employ this method for the inspection of vehicles in service.▼M5
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Vehicle categoriesValues
expressed in
dB (A)
5.2.2.1.1. Vehicles intended for the carriage of passen-
gersand equipped with not more than nine
seats, including the driver's seat 77
5.2.2.1.2. Vehicles intended for the carriage of passen-
gers and equipped with more than nine seats,
including the driver'ss eat, and having a
maximum permissible mass of more than 3,5
tonnesand:
5.2.2.1.2.1. — with an engine power of less than 150 kW 80
5.2.2.1.2.2. — with an engine power of not less than 150
kW 83
5.2.2.1.3. Vehicles intended for the carriage of passen-
gers and equipped with more than nine seats,
including the driver'ss eat; vehiclesintended
for the carriage of goods:
5.2.2.1.3.1. — with a maximum permissible mass not
exceeding 2 tonnes78
5.2.2.1.3.2. — with a maximum permissible mass
exceeding 2 tonnesbut not exceeding 3,5
tonnes79
5.2.2.1.4. Vehiclesintended for the carriage of goods
and having a maximum permissible mass
exceeding 3,5 tonnes
5.2.2.1.4.1. — with an engine power of less than 75 kW 81
5.2.2.1.4.2. — with an engine power of not less than 75
kW but less than 150 kW 83
5.2.2.1.4.3. — with an engine power of not less than 150
kW 84
However,
— for vehiclesof categories5.2.2.1.1 and 5.2.2.1.3, the limit
values shall be increased by 1 dB (A) if they are equipped
with a direct injection diesel engine,
— for vehicles with a maximum permissible mass of over two
tonnes designed for off-road use, the limit values are
increased by 1 dB (A) if their engine power is less than
150 kW and 2 dB (A) if their engine power isequal to or
greater than 150 kW.
5.2.2.2. Measuring instruments
5.2.2.2.1. Acoustic measurements
The apparatus used for measuring the noise level must be a
precision sound-level meter of the type described in Publica-
tion 179 ‘Precision sound level meters’, second edition, of the
International Electrotechnical Commission (IEC). Measure-
ments must be carried out using the ‘fast’ response of the
sound-level meter and the ‘A’ weighting curve which are also
described in that publication.
At the beginning and end of each set of measurements, the
sound-level meter must be calibrated according to the manufac-
turer's instructions by means of an appropriate sound source
(e.g. a pistonphone). The test must be considered invalid if
the sound-level meter errors registered during this calibration
exceed 1 dB.
5.2.2.2.2. Speed measurements
The engine speed and vehicle speed on the test section shall be
determined with an accuracy of 3 % or better.1970L0157 — EN — 29.06.1987 — 008.001 — 6
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5.2.2.3. C onditionsof meas urement
5.2.2.3.1. Test site
The test site must consist of a central acceleration section
surrounded by a substantially flat test area. The acceleration
section must be level; the track surface must be dry and such
that rolling noise remains low.
The test track must be such that the conditions of a free sound
field between the sound source and the microphone are attained
to within 1 dB. Thiscondition s hall be deemed to be met if
there are no large sound-reflecting objects such as fences,
rocks, bridges or buildings within 50 m of the centre of the
acceleration section. The surface of the site must be made of
hard materials such as concrete, asphalt or any other acousti-
cally equivalent material within a minimum radiusof 10 m
around the centre of the acceleration section and be free of
powdery snow, tall grass, loose soil or cinders.
There must be no obstacle which could affect the sound field
within the vicinity of the microphone and no persons shall
stand between the microphone and the sound source. The
observer carrying out the measurements must so position
himself as not to affect the readings of the measuring instru-
ment.
5.2.2.3.2. Meteorological conditions
Measurements must not be made in poor atmospheric condi-
tions. It must be ensured that the results are not affected by
gusts of wind.
5.2.2.3.3. Ambient noise
For measurements, the A-weighted sound level of sound
sources other than those of the vehicle to be tested and of
wind effects must be at least 10 dB(A) below the sound level
produced by the vehicle. A suitable windscreen may be fitted
to the microphone provided that account istaken of itseffect
on the sensitivity and directional characteristics of the micro-
phone.
5.2.2.3.4. Condition of the vehicle
For these measurements, the vehicle must be in running order
asdefined in item 2.6 of Annex I to Directive 70/156/EEC and,
except in the case of vehicles which cannot be uncoupled,
without trailer or semi-trailer.
The vehicle's tyres must be of the type normally fitted to such
vehiclesby the manufacturer and mus t be inflated to the appro-
priate pressure(s) for the unladen vehicle.
Before the measurements are made, the engine must be brought
to itsnormal operating condition asregardstemperatures ,
settings, fuel, spark plugs, carburettor(s), etc. (as appropriate).
If the vehicle isfitted with fan(s ) having an automatic
actuating mechanism, this system must not be interfered with
during the measurements.
Only the normal highway drive must be engaged in vehicles
with more than two drive wheels.
5.2.2.4. Method of measurement
5.2.2.4.1. Nature and number of measurements
The maximum sound level expressed in A-weighted decibels
(dB(A)) shall be measured as the vehicle is driven between
linesAA ′and BB ′(Figure 1). The measurement shall be
invalid if an abnormal discrepancy between the peak value
and the general sound level is recorded.
At least two measurements must be taken on each side of the
vehicle.
5.2.2.4.2. Positioning of the microphone
The microphone must be located at a distance of 7·5 ± 0·2 m
from the reference line CC ′(Figure 1) of the track and 1·2 ±
0·1 m above the ground. Its axis of maximum sensitivity must
be horizontal and perpendicular to the path of the vehicle (line
CC′).1970L0157 — EN — 29.06.1987 — 008.001 — 7
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5.2.2.4.3. Conditionsof operation
5.2.2.4.3.1. General conditions
For all measurements, the vehicle must be driven in a straight
line over the acceleration section in such a way that the long-
itudinal median plane of the vehicle is as close as possible to
the line CC ′.
The vehicle must approach the line AA ′at a steady initial road
speed as specified in items 5.2.2.4.3.2 and 5.2.2.4.3.3. When
the front end of the vehicle hasreached the line AA ′, the
throttle must be fully opened as quickly as practically possible.
This throttle position must be maintained until the rear end of
the vehicle reachesthe line BB ′; the throttle must then be
returned to the idling position as quickly as possible.
The trailersof articulated vehicleswhich cannot be uncoupled
must not be taken into account as regards the crossing of line
BB′.
5.2.2.4.3.2. Approach speed
The vehicle must approach the line AA ′at a steady speed
corresponding to the lower of the following two speeds:
— the speed corresponding to an engine speed equal to three-
quartersof the s peed, S, at which the engine developsits
rated maximum power,
— 50 km/h.
However, if in the case of vehicles equipped with an automatic
transmission having more than two discrete ratios there is a
change-down to first gear during the test, the manufacturer
may select either of the following test procedures:
— the speed, V, of the vehicle shall be increased to a
maximum of 60 km/h in order to avoid such a change-
down, or
— the speed, V, shall remain at 50 km/h and the fuel supply to
the engine shall be limited to 95 % of the supply necessary
for full load. This condition is considered to be satisfied:
— in the case of a spark-ignition engine, when the angle of
the throttle opening is90 %, and
— in the case of a compression-ignition engine, when the
movement of the central rack of the injection pump is
limited to 90 % of itstravel.
If the vehicle is equipped with an automatic transmission
which has no manual override, it must be tested at different
approach speeds, namely 30, 40 and 50 km/h, or at three-
quartersof maximum road s peed if thisvalue islower.
The test result shall be that obtained at the speed which
producesthe maximum s ound level.
5.2.2.4.3.3. Choice of gear ratios(in vehiclesfitted with gearboxes ).
5.2.2.4.3.3.1. Manually-operated, non-automatic gearbox.
5.2.2.4.3.3.1.1. Vehiclesin categoriesM1and N1equipped with a manually
operated gearbox having not more than four forward gear ratios
must be tested in second gear.
Vehiclesin thes e categoriesequipped with a manually operated
gearbox having more than four forward gear ratiosmus t be
tested in second and third gears successively. Only overall
gear ratios intended for normal road use shall be considered.
The arithmetic mean of the sound levels recorded for each of
these two conditions shall be calculated.
However, the vehiclesin category M1having more than four
forward gearsand equipped with an engine developing a
maximum power greater than 140 kW, and whose permissible
maximum-power/maximum-mass ratio exceeds 75 kW/t, may
be tested in third gear only, provided that the speed at which
the rear of the vehicle passes the line BB ′in third gear is
greater than 61 km/h.1970L0157 — EN — 29.06.1987 — 008.001 — 8
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5.2.2.4.3.3.1.2. Vehiclesother than thos e in categoriesM1and N1(1) in which
the total number of forward gear ratiosisX (including the
ratiosobtained by meansof an auxiliary gearbox or a
multiple-ratio drive axle) must be tested using, in turn, ratios
equal to or higher thanX
2(2). The test result will be that
obtained from the ratio producing the maximum sound level.
Notwithstanding the provisions of items 1.1.2 and 1.1.4, vehi-
cles having the same type of engine and exhaust and intake
systems, but different lengths or widths and different overall
gear ratios, may be regarded as vehicles of the same type. In
this case, it will be sufficient to test a single vehicle represen-
tative of the type in question, in principle, by selecting as the
test vehicle that with the lowest weight in running order.
If the maximum sound level is obtained between the ratiosX
2
and X, the vehicle selected shall be deemed representative of
itstype.
If this is not the case, the tests must be extended to cover the
whole range of overall gear ratiosto be taken into cons idera-
tion for vehiclesof thistype.
5.2.2.4.3.3.2. Automatic gearbox fitted with manual selector.
Automatic transmission equipped with manual override.
The test shall be conducted with the selector in a position
recommended by the manufacturer for ‘normal’ driving.
5.2.2.5. Interpretation of results
5.2.2.5.1. To take account of inaccuracies in the measuring instruments,
the result obtained from each measurement shall be determined
by deducting 1 dB(A) from the meter reading.
5.2.2.5.2. The measurements shall be considered valid if the difference
between two consecutive measurements on the same side of
the vehicle doesnot exceed 2 dB(A).
5.2.2.5.3. The highest sound level measured shall constitute the test
result. Should the result exceed the maximum permissible
sound level for the category of vehicle tested by 1 dB(A), two
further measurements shall be made. Three of the four
measurements thus obtained must fall within the prescribed
limits.
5.2.3. Sound level of the stationary vehicle
5.2.3.1. Sound level in the vicinity of vehicles
In order to facilitate subsequent checks on vehicles in use, the
sound level must be measured close to the exhaust system
outlet in accordance with the following requirementsand the
measurement results entered in the test report drawn up for
the purpose of issuing the certificate referred to in Annex III.
5.2.3.2. Measuring instruments
5.2.3.2.1. Acoustic measurements
A precision sound-level meter as defined in item 5.2.2.2.1 must
be used for the measurements.
5.2.3.2.2. Measurements of engine speed
The engine speed shall be determined by means of a tach-
ometer having an accuracy of 3 % or better. The tachometer
must be a separate one from the one of the vehicle.1970L0157 — EN — 29.06.1987 — 008.001 — 9
(1) In accordance with the definition given in item 0.4 of Annex I to Directive 70/156/EEC
(OJ No L 42, 23. 2. 1970).
(2)I fX
2does not correspond to a whole number, the nearest higher ratio must be used.▼M4
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5.2.3.3. C onditionsof meas urement
5.2.3.3.1. Test site (Figure 2)
Any area not subject to significant acoustic disturbance may be
used as a test site. Flat surfaces which are covered in concrete,
asphalt or any other hard surfacing and possess a high degree
of reflectivity are particularly suitable; surfaces consisting of
earth which has been tamped down must not be used. The test
site must be in the form of a rectangle, the sides of which are
at least 3 m from the sides of the vehicle. This rectangle must
not contain any significant obstacles, e.g. an individual other
than the observer and the driver. The vehicle must be posi-
tioned within the abovementioned rectangle so that the
microphone is at least 1 m from any kerbstone.
5.2.3.3.2. Meterological conditions
Measurements must not be made in poor atmospheric condi-
tions. It must be ensured that the results are not affected by
gusts of wind.
5.2.3.3.3. Ambient noise
Readings on the measuring instruments produced by ambient
noise and wind must be at least 10 dB(A) below the sound
level to be measured. A suitable windscreen may be fitted to
the microphone provided that account istaken of itseffect on
the sensitivity of the microphone.
5.2.3.3.4. Condition of the vehicle
The vehicle engine must be brought to normal running
temperature before measurements commence. If the vehicle is
fitted with fan(s) having an automatic actuating mechanism,
this system shall not be interfered with during the sound-level
measurements.
During measurements, the gear lever must be in the neutral
position.
5.2.3.4. Method of measurement
5.2.3.4.1. Nature and number of measurements
The maximum sound level expressed in A-weighted decibels
(dB(A)) must be measured during the operating period referred
to in item 5.2.3.4.3.
At least three measurements must be taken at each measuring
point.
5.2.3.4.2. Position of the microphone (Figure 2)
The microphone must be located level with the exhaust outlet
or 0·2 m above the test-track surface, whichever is the higher.
The microphone diaphragm must face the exhaust outlet at a
distance of 0·5 m from the latter. The axis of maximum sensi-
tivity of the microphone must be parallel to the track surface at
an angle of 45º ± 10º to the vertical plane defined by the direc-
tion in which the exhaust gases are emitted.
The microphone must be positioned to the side of this vertical
plane which gives the greatest possible distance between the
microphone and the vehicle contour.
If the exhaust system has several outlets, the centres of which
are not more than 0·3 m apart, and which are connected to the
same silencer, the microphone must face the outlet closest to
the vehicle contour or the outlet which isthe highes t above
the track surface. In all other cases separate measurements
must be taken at each of them, the highest figure recorded
being taken asthe tes t value.
In the case of vehicles fitted with a vertical exhaust outlet (e.g.
commercial vehicles), the microphone must be positioned at
the level of the exhaust outlet, facing upwards with its axis
vertical. It must be positioned at a distance of 0·5 m from the
side of the vehicle closest to the exhaust outlet.
Where the design of the vehicle is such that the microphone
cannot be located as shown in Figure 2 because of the presence
of obstacles which form part of the vehicle (e.g. spare wheel,
fuel tank, battery compartment), a drawing clearly indicating1970L0157 — EN — 29.06.1987 — 008.001 — 10
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the position for the microphone must be made when the
measurement is conducted. As far as possible, the microphone
must be more than 0·5 m from the nearest obstacle, and its axis
of maximum sensitivity must face the exhaust outlet from the
position least concealed by the abovementioned obstacles.
5.2.3.4.3. Conditionsof engine operation
Engine speed must be stabilized at three-quarters of the speed
(S) at which the engine developsrated maximum power.
When constant engine speed is reached, the throttle must be
rapidly returned to the idling position. The sound level must
be measured over an operating period comprising brief mainte-
nance of constant engine speed and the entire deceleration
period, the maximum sound-level meter reading being taken
as the test result.
5.2.3.5. Results (test report)5.2.3.5.1. The test report drawn up for the purpose of issuing the certifi-
cate referred to in Annex III shall indicate all relevant data,
particularly those used in measuring the sound of the stationary
vehicle.
5.2.3.5.2. Readings, rounded off to the nearest decibel, shall be taken
from the measuring instrument.
Only those values obtained from three consecutive measure-
mentswhich do not differ by more than 2 dB(A) res pectively
will be taken into consideration.
5.2.3.5.3. The highest of these three values shall constitute the test result.
5.3. Exhaustsystemscontainingfibrousmaterials
5.3.1. Fibrous materials shall not be used in the construction of silen-
cers unless suitable measures are undertaken at the design or
production stages to ensure that the efficiency required to
comply with the limitsimpos ed in item 5.2.2.1 isachieved on
the road. Such a silencer shall be considered to be efficient on
the road if the exhaust gases are not in contact with the fibrous
materials or if the silencer of the prototype vehicle tested in
accordance with the requirementsof items5.2.2 and 5.2.3 has
been put into a normal state for road use before the sound-level
measurements are taken. This can be achieved by using one of
the three tests described in items 5.3.1.1, 5.3.1.2 and 5.3.1.3,
below, or by removing the fibrousmaterialsfrom the s ilencer.
5.3.1.1. Conti nuousroad operation for 10 000 km
5.3.1.1.1. About half this operation shall consist of town driving and the
other half of long-distance runs at high speed; continuous road
operation can be replaced by a corresponding test-track
programme.
5.3.1.1.2. The two speed regimes must be alternated on several occa-
sions.
5.3.1.1.3. The complete test programme must include a minimum of 10
breaksof at leas t three-hoursduration in order to reproduce
the effectsof cooling and any condens ation which may occur.
5.3.1.2. C onditioning on a test bench
5.3.1.2.1. Using standard parts and observing the vehicle manufacturer's
instructions, the silencer must be fitted to the engine, which is
coupled to a dynamometer.
5.3.1.2.2. The test must be conducted in six six-hour periods with a break
of at least 12 hours between each period in order to reproduce
the effectsof cooling any condens ation which may occur.
5.3.1.2.3. During each six-hour period, the engine shall be run under the
following conditionsin turn:
1. Five minutesat idling s peed;
2. One-hour sequence under ¼ load at ¾of rated maximum
speed (S);
3. One-hour sequence under ½ load at ¾of rated maximum
speed (S);1970L0157 — EN — 29.06.1987 — 008.001 — 11
▼M3
4. 10-minute sequence under full load at ¾of rated maximum
speed (S);
5. 15-minute sequence under ½ load at rated maximum speed
(S);
6. 30-minute sequence under ¼ load at rated maximum speed
(S).
Total duration of the six sequences: three hours.
Each period must comprise two sets of the six abovementioned
sequences.
5.3.1.2.4. During the test, the silencer must not be cooled by a forced
draught simulating normal airflow around the vehicle. Never-
theless, at the request of the manufacturer, the silencer may
be cooled in order not to exceed the temperature recorded at
itsinlet when the vehicle isrunning at maximum s peed.
5.3.1.3. C onditioning by pulsation
5.3.1.3.1. The exhaust system or components thereof must be fitted to the
vehicle referred to in item 2.3 or the engine referred to in item
2.4. In the former case the vehicle must be mounted on a roller
dynamometer. In the second case, the engine must be mounted
on a dynamometer.
The test apparatus, a detailed diagram of which is shown in
Figure 3, must be fitted at the outlet of the exhaust system.
Any other apparatusproviding equivalent res ultsisacceptable.
5.3.1.3.2. The test apparatus must be adjusted in such a way that the
exhaust-gas flow is alternately interrupted and re-established
by the quick-action valve for 2 500 cycles.
5.3.1.3.3. The valve must open when the exhaust-gas back pressure,
measured at least 100 mm downstream of the intake flange,
reaches a value of between 0·35 and 0·40 bar. It must close
when this pressure does not differ by more than 10 % from
itss tabilized value with the valve open.
5.3.1.3.4. The time-delay switch shall be set for the duration of gas
exhaust resulting from the provisions laid down in item
5.3.1.3.3 above.
5.3.1.3.5. Engine speed must be 75 % of the speed (S) at which the
engine developsmaximum power.
5.3.1.3.6. The power indicated by the dynamometer must be 50 % of the
full-throttle power measured at 75 % of engine speed (S).
5.3.1.3.7. Any drainholes must be closed off during the test.
5.3.1.3.8. The entire test must be completed within 48 hours.
If necessary, one cooling period will be observed after each
hour.
5.3.2. If the provisions of Article 8 (3) of Directive 70/156/EEC
concerning EEC type-approval are to be applied, the test
method set out in item 5.3.1.2 above must be employed.1970L0157 — EN — 29.06.1987 — 008.001 — 12
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Figure 1
Microphonepositionsforthemeasurementofamovingvehicle1970L0157 — EN — 29.06.1987 — 008.001 — 13
▼M3
Figure 2
Testsiteandmicrophonepositionsforthemeasurementofastationaryvehicle
All distances are given in metres1970L0157 — EN — 29.06.1987 — 008.001 — 14
▼M3
Figure 3
Testapparatusforconditioningbypulsation
1. Inlet flange or sleeve for connection to the rear of the test exhaust system2. Hand-operated regulating valve3. Compensating reservoir having a capacity of from 35 to 40 litres4. Pressure switch with an operating range of 0·05 to 2·5 bar
5. Time delay switch
6. Impulse counter7. Quick response valve, such as exhaust brake valve 60 mm in diameter, operated by a pneumatic cylinder with an
output of 120 N at 4 bar. The response time, both when opening and closing, must not exceed 0·5 second
8. Exhaust gas evacuation9. Flexible pipe
10. Pressure gauge1970L0157 — EN — 29.06.1987 — 008.001 — 15
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ANNEX II
EEC TYPE-APPROVAL OF EXHAUST SYSTEMS AS SEPARATE
TECHNICALUNITS(REPLACEMENTEXHAUSTSYSTEMS)
0. SCOPE
ThisAnnex appliesto the type-approval, ass eparate technical
unitswithin the meaning of Article 9a of Directive 70/156/
EEC, of exhaust systems or components thereof to be fitted to
one or more given typesof motor vehicle in categoriesM1and
N1asreplacement parts .
1. DEFINITIONS
1.1. ‘Replacement exhaust system or component thereof’ means any
part of the exhaust system defined in item 1.2.1 of Annex I
intended to replace on a vehicle a part of the type granted
EEC type-approval with the vehicle in accordance with Annex
I.
2. APPLICATION FOR EEC TYPE-APPROVAL
2.1. Application for EEC type-approval in respect of a replacement
exhaust system or component thereof as a separate technical
unit must be submitted by the vehicle manufacturer of the
separate technical unit in question or by their authorized repre-
sentatives.
2.2. Application for EEC type-approval in respect of each type of
replacement exhaust system or component thereof must be
accompanied by the undermentioned documentsin triplicate
and the following information:
2.2.1. — a description of the type(s) of vehicle to which the system
or componentsthereof are to be fitted with reference to the
characteristics mentioned in item 1.1 of Annex I. The numbers
and/or symbols designating the engine and vehicle type must
be indicated;
2.2.2. — a description of the replacement exhaust system indicating
the relative position of each system component, together with
mounting instructions;
2.2.3. — detailed drawingsof each component, s o that they can be
easily located and identified, and reference to the materials
used.
These drawings must indicate the place provided for the
compulsory affixing of the EEC type-approval.
2.3. At the request of the technical service concerned, the applicant
must submit:
2.3.1. — two examples of the system in respect of which application
for EEC type-approval hasbeen made;
2.3.2. — an exhaust system of the type originally fitted to the vehicle
when EEC type-approval wasgranted;
2.3.3. — a vehicle representative of the type to which the system is
to be fitted:
— which, asfar asitsnois e level when moving isconcerned,
must be in such a condition that it respects the limits in
item 5.2.2.1 of Annex I and doesnot exceed by more than
3 dB(A) the valuesobtained during the type-approval tes ts
and
— which, asfar asitsnois e level when s tationary is
concerned, respects the value obtained during the type-
approval;
2.3.4. — a separate engine corresponding to the type of vehicle
described above.
3. MARKINGS
3.1. The replacement exhaust system or its components, excluding
fixing hardware and pipesmus t bear:1970L0157 — EN — 29.06.1987 — 008.001 — 16
▼M3
3.1.1. — the trade mark or trade name of the manufacturer of the
replacement system and its components;
3.1.2. — the manufacturer'scommercial des cription;3.1.3. — the EEC type-approval number preceded by the distinctive
letter(s) of the country granting EEC type-approval
►
A2(1)◄.
3.2. These marks must be clearly legible and indelible.
4. EEC TYPE-APPROVAL
4.1. If an application within the meaning of item 2.1 isapproved,
the competent authority will draw up a certificate corre-
sponding to the model shown in Annex IV. The type-approval
number must be preceded by the distinctive letter(s) of the
country granting EEC type-approval.
5. SPECIFICATIONS5.1. General specifications
5.1.1. The replacement exhaust system or component thereof must be
designed, constructed and capable of being mounted so as to
ensure that the vehicle complies with the provisions of this
Directive under normal conditions of use, notwithstanding any
vibrationsto which it may be s ubject.
5.1.2. The exhaust system or components thereof must be designed,
constructed and capable of being mounted so that reasonable
resistance to the corrosion phenomena to which it/they is/are
exposed is obtained having regard to the conditions of use of
the vehicle.
5.2. Specificationsrelatingtosoundlevels
5.2.1. The acoustic efficiency of the replacement exhaust system or
component thereof must be checked using the methods
described in items 5.2.2.4 and 5.2.3.4 of Annex I.
When the replacement exhaust system or component thereof is
mounted on the vehicle referred to in item 2.3.3 of thisAnnex,
the sound levels obtained using the two methods (stationary
and moving vehicle) must satisfy one of the following condi-
tions:
5.2.1.1. they must not exceed the values obtained when this type of
vehicle wasgranted EEC type-approval;
5.2.1.2. they must not exceed the sound level values measured on the
vehicle, referred to in item 2.3.3, when thisisfitted with an
exhaust system of the same type as that fitted to the vehicle
when EEC type-approval wasgranted.
5.3. Measurement ofvehicleperformance
5.3.1. The replacement exhaust system or components thereof must
be such as to ensure that vehicle performance is comparable
with that achieved with the original equipment exhaust system
or component thereof.
5.3.2. The replacement exhaust system or, depending on the manufac-
turer's choice, the components of this system must be
compared with the original equipment exhaust system or
componentsthereof, which are als o in new condition, fitted in
turn to the vehicle referred to in item 2.3.3.
5.3.3. The check must take the form of a measurement of pressure
loss under the conditions specified in item 5.3.4.1 or 5.3.4.2.
The value measured with the replacement exhaust system
must not exceed the value measured with the original equip-
ment system by more than 25 % under the conditions
mentioned below.1970L0157 — EN — 29.06.1987 — 008.001 — 17
(1) B = Belgium, D = Germany, DK = Denmark, E = Spain, F = France, ►M6EL =
Greece ◄, I = Italy, IRL = Ireland, L = Luxembourg, N L = Netherlands, P =
Portugal, UK = United Kingdom.
▼M3
5.3.4. Test Method
5.3.4.1. Engine test method
The measurement must be conducted on the engine referred to
in item 2.3.4 coupled to a dynamometer.
With the throttle completely open, the bench shall be so
adjusted as to obtain the engine speed (S) corresponding to
the rated maximum power of the engine.
For the measurement of back pressure, the pressure tap must be
placed at the distance from the exhaust manifold specified in
Figures1, 2 and 3.
5.3.4.2. Vehicle test method
The measurements must be carried out on the vehicle referred
to in item 2.3.3.
The test must be conducted:
— either on a road, or
— on a roller dynamometer.
With the throttle completely open, the engine must be loaded
so as to obtain the engine speed (S) corresponding to the rated
maximum power.
For the measurement of back pressure, the pressure tap must be
placed at the distance from the exhaust manifold specified in
Figures1, 2 and 3.
5.4. Additional provisions in respect of exhaust systems or
componentsthereoffilledwithfibrousmaterials
Fibrous materials must not be used in the manufacture of repla-
cement exhaust systems or components thereof unless
appropriate measures are taken during the design and produc-
tion stages to ensure that a level of efficiency is attained
corresponding to the limits set out in item 5.2.2.1 of Annex I.
Such a silencing system is deemed to be effective in traffic if
the exhaust gases are not in contact with the fibrous materials
or if, after the removal of the fibrous materials, the sound
levelscomply with the requirementss et out in item 5.2.1
above, when the exhaust system is tested on a vehicle in accor-
dance with the methodsdes cribed in items5.2.2 and 5.2.3 of
Annex I.
If this condition is not observed, the entire exhaust system
must be subjected to conditioning. This must be done using
one of the three methodsdes cribed in items5.3.1.1, 5.3.1.2
and 5.3.1.3 of Annex I.
After conditioning, the sound level must be checked as speci-
fied in item 5.2.1 above.
When the procedure described in item 5.2.1.2 is employed, the
applicant for EEC type-approval may ask for the conditioning
of the original equipment exhaust system or submit one which
hasbeen emptied.
6. CONFORMITY OF PRODUCTION
6.1. Any replacement exhaust system or component thereof bearing
an EEC type-approval number pursuant to this Directive must
conform to the approved type of exhaust system and comply
with the requirementsof item 5 above.
6.2. In order to check conformity asrequired by item 6.1 above, an
exhaust system or component thereof bearing the EEC type-
approval number must be taken from the series. Production is
deemed to conform with the requirementsof thisDirective if
the sound levels measured in accordance with item 5.2 do not
exceed the level measured during the EEC type-approval tests
of this type of exhaust system or component thereof by more
than 1 dB(A).1970L0157 — EN — 29.06.1987 — 008.001 — 18
▼M3
Backpressure—measuringpoints
Figure 1
Figure 2 (1)
Figure 3
1970L0157 — EN — 29.06.1987 — 008.001 — 19
(1) If this is not possible, use Figure 3.
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ANNEX III
MODEL
Maximumsize:A4(210×297mm)
1970L0157 — EN — 29.06.1987 — 008.001 — 20
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1970L0157 — EN — 29.06.1987 — 008.001 — 21
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ANNEX IV
MODEL
Maximumsize:A4(210mm×297mm)
►(1)A2
►(2)M61970L0157 — EN — 29.06.1987 — 008.001 — 22
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1970L0157 — EN — 29.06.1987 — 008.001 — 23