thats the problem the police officers are not qualified to be making judgement on the mechanical fitnes of the vehicle yes they have their little measuring devices for to low. and too loud but too loud can be debunk in 30 seconds by pulling out an adr's handbook and proving the test isn't being carried out properly.(it can not be properly carried out on the street.) i'm glad i wasn't at that particular downshift meet probably would have got screwed. (currently have no back seat it's getting reupholstered) you have to ask if they aren't qualified to be judging the vehicle how can they be allowed to issue fines upon their unqualified observations.an external gate isn't illegal having an external gate that dumps to atmo (screamer is)
i deal with transport on a regular basis as a cabbie and when you dealing with a transport inspection officer you know that what they are picking you for is right because they are all qualified mechanics/engineers and deal with these things daily.
for to loud they must follow this as set forth by the ADR's
1. Measuring Instruments
1.1 A sound level meter of high precision complying at least with the specifications of Publication No 651 (1979) - “Precision sound level meters” of the International Electrotechnical Commission (IEC), or Type 1 of Australian Standard 1259-1982 - “Sound Level Meters”, concerning the characteristics of sound level meters, shall be used. Measurement shall be carried out with a weighting network and a time constant conforming to “curve A” and the “fast response” respectively.
1.2 The sound level meter shall be calibrated against a standard noise source immediately before and after each series of test runs. If the meter reading obtained from either of these calibrations deviates by more than 1dB(A) from the corresponding reading taken at the time of the last free-field calibration the test shall be considered invalid. The actual deviation shall be recorded.
1.3 The rotational speed of the engine shall be measured by an independent tachometer whose accuracy is within 3 per cent of the actual speed of rotation.
3. Procedure for Stationary Vehicles
(Refer to diagram - Section 4)
3.1 Requirements for tests on stationary vehicles.
3.1.1 Tests on stationary vehicles (exhaust noise tests) should ideally be carried out consecutively with the tests on the same vehicle in motion.
3.1.2 The measurements shall be made at an open site where the ambient and wind noise levels are at least 10 dB(A) below the noise level being measured. The site may take the form of an open space where a rectangle with sides no closer than 3 m from the extremities of the vehicle can be described. The test site surface should be practically level, consisting of concrete, asphalt or similar material and not covered with powdery snow, tall grass, loose soil, ashes or the like.
3.1.3 Measurements shall not be made under adverse weather conditions. Any sound peak which appears to be unrelated to the characteristics of the general sound level of the vehicle shall be ignored in taking the readings. If a wind guard is used, its influence on the sensitivity and the directional characteristics of the microphone shall be taken into account.
3.1.4 Whilst testing is in progress no person other than any occupants of the vehicle shall be within 1 m of the microphone in use. No person or object other than the person conducting the test and an observer or the objects necessary for the performance of the test shall be within 3m of the microphone in use.
3.1.5 Before the measurements are begun, the engine shall be brought to its normal operating conditions as regards: temperatures, tuning, fuel, sparking plugs, carburettor(s), etc. as appropriate.
3.1.6 The use of special acoustic shielding may be permitted in unusual cases. Refer to paragraph
3.2 Microphone position.
3.2.1 The microphone shall be directed towards the orifice of the exhaust outlet and shall be supported by a tripod or similar device not providing excessive acoustic reflection.
3.2.2 The nominal axis of maximum sensitivity of the microphone shall be substantially parallel to the test site surface.
3.2.3 The height of the microphone above the test site surface shall be equal to that of the orifice of the exhaust outlet + 25 mm but shall not be less than 200 mm above the test site surface.
3.2.4 The distance of the microphone from the orifice of the exhaust outlet shall be:
3.2.4.1 in the case of a
‘Goods Vehicle’ or
‘Omnibus’ 1050 mm
+ 50 mm,
3.2.4.2 in the case of any other vehicle 525 mm
+25 mm.
3.2.5 For vehicles fitted with one exhaust outlet which is at a height above the test site surface of less than 1500 mm, the nominal axis of maximum sensitivity of the microphone shall make an angle of 45 degrees + 10 degrees with the principal direction of the gas flow from the exhaust outlet.
3.2.5.1 In selecting this microphone position the microphone shall be placed so that the
greatest possible distance is achieved between it and the vehicle.
3.2.6 For vehicles fitted with one exhaust outlet which is at a height above the test site surface of at least 1500 mm, the nominal axis of maximum sensitivity of the microphone shall make an angle of 90 degrees + 10 degrees with the longitudinal centreline of the vehicle.
3.2.6.1 In selecting this microphone position the microphone shall be placed so that the
greatest possible distance is achieved between it and the vehicle.
3.2.7 For vehicles fitted with two or more exhaust outlets spaced less than 500 mm apart and connected to a single silencer only one microphone position shall be used. That position shall be selected in accordance with the procedure described in the preceding paragraphs in respect of an exhaust outlet which results in the microphone being at the greatest possible distance from the vehicle.
3.2.8 For vehicles fitted with two or more exhaust outlets connected to separate silencers or spaced more than 500 mm apart, each exhaust outlet shall be treated separately as if it was the only one.
3.2.9 Notwithstanding anything to the contrary in the preceding paragraphs if the microphone positioning procedures result in no suitable position due to an obstruction being part of the vehicle or in an obstruction being directly between the microphone and the exhaust outlet, the requirements of paragraphs 3.2.2 and 3.2.3 may be varied.
3.3 Vehicle operation and noise measurement.
3.3.1 The vehicle shall be stationary with the transmission in neutral or, in the case of a vehicle with automatic transmission, with the gear selector in the “park” position if such a position is provided.
3.3.2 In the case of Goods Vehicles and Omnibuses powered by a ‘Diesel Engine’ the engine shall be operated in accordance with the following procedure.
3.3.2.1 With the engine at idling speed the accelerator pedal of the vehicle shall be
depressed as rapidly as possible and kept fully depressed until the speed of the engine is substantially stable at maximum (or governed) speed. The accelerator pedal shall then be permitted to return to its original position as rapidly as possible and left in that position until the engine has returned to idling speed.
3.3.2.2 A single noise level measurement shall be made for each microphone position in
use by noting the maximum noise level indicated during this procedure.
3.3.3 In the case of all other vehicles the engine shall be operated in accordance with the following procedure.
3.3.3.1 The engine shall be brought to 3/4
‘ESMP’ and stabilised at that speed.
3.3.3.2 A single noise level measurement shall then be made.
3.3.4 The specified procedure shall be repeated until four consecutive readings having a range less than or equal to 1dB(A) are obtained for each microphone position used.
3.4 Interpretation of results for stationary vehicles.
3.4.1 Where one microphone position is used the noise level of the vehicle shall be the arithmetic mean of the four readings specified in paragraph 3.3.4.
3.4.2 When the sound level of the vehicle has been calculated, non-integer results shall be rounded down to the nearest whole decibel.
3.4.3 Where more than one microphone position is used the noise level at each microphone position shall be determined as if it was the only one. The noise level of the vehicle shall be the higher or highest noise level so calculated.
3.4.4 If the microphone position is less than 1m from the engine compartment of the vehicle the calculated noise level shall be reduced by 2dB(A) unless the provisions of paragraph 3.4.5 have been invoked.
3.4.5 Where the mechanical noise of the vehicle (for example engine or transmission noise) can be shown to increase the measured noise level by 2dB(A) or more, special acoustic shielding may be fitted to mask this source so that the test is carried out on the exhaust noise alone.
3.4.5.1 Such shielding shall not interfere with the normal acoustic properties of the
‘
Noise Reduction System’.
3.4.5.2 Where such shielding is used both noise levels (with and without the shielding)
shall be reported. The noise level with the shielding in place shall be used to assess the vehicle’s compliance.
3.4.5.3 Where such shielding is used the provisions of paragraph 3.4.4 shall not apply.
in a roadside test it is impractical to get an acurate reading and setup the equipment correctly thus all rodside test could be debunked in court
) A mate in a very tidy 180 got told to f**k off go home don't come back, the first thing that came out of the officers mouth was "Have you ever been in trouble fr having a modified vehicle" mate's response was "no", his reply "Well you about to get in trouble for it today". He got done for "exhaust sticking too far out", "not enough padding on the seat", than the usual ones, too low, too noisy (he measured it on a fucked surface, the car does actually sit 100mm on FLAT Ground, and he didn't noise test it correctly either, held the dB reader right up to the exhaust tip (should be 3 m back and at 30% engine load if i remember correctly?). He decided it would be a good idea to rev it to redline after the car had been sitting off for near an hour, He will be going to court, and questioning the cop if he had the correct certifications to even be touching anything.
