Car Exhaust Noise
Discussion
Back in August I was followed by the local Norfolk BiB in my car and eventually stopped about 600m from home and told "my exhausts looked loud and would I mind going back to the local station to have a dB check ", I was more than happy to as I thought there was nothing wrong with my car. Exhaust was on it when I bought it 3 years ago and no MOT station has picked up on excessive noise before.
The car is a UK spec 1996 Toyota Celica 2.0 GT with twin rear pipes.
Anyway back to the local station I go where they set up their test. They ask me what the Red line is on the car and does the rev counter work. I say it's working fine and it is a 7K red line.
They look up on their form and ask me to hold the revs at 3/4 throttle (5250 RPM) for 10 seconds while they take a reading. This they did 3 times on each side of the car.
They then tell me that the average dB reading is 94.1dB. The legal limit is meant to be 82dB and they prosecute above 90
Anyway They give me a £30 fine and tell me to get the car quieter. No re-test, no producer just told to watch my back as the next time it would be court, points and possibly the car crushed
The following day I talk to the type approval and legal guys at work. they said that the Police have it wrong. I then look into the ISO5130 which they readily quote on their paperwork. After some careful reading I find the section about the RPM measurements and yes, the Police have it totally wrong.
Remeber they asked me to have the car sitting at 5250RPM.... well ISO 5130 section 6.4.3 states that:
The target engine speed for category M & N vehicles shall be :
75% of the rated engine speed for vehicles with max power equal to or less than 5000Rpm
3750 RPM for vehicles with a rated max power between 5000 but less that 7500 RPM (this is the category my vehicle falls into)
50% of the engine speed for vehicles with a max power rating over 7500 RPM
They tested 1500RPM higher than the ISO Spec says.
I querey this with the Police, and they say that they will look into it, but if the PC who did the test feels that it was done correctly then the £30 fine stands.
I tell them that their paperwork is incorrect, but they tell me that they are not looking into that, just that the test was done to their procedure and now I have to pay the £30 fine or go to court.
I have 10 days now to either pay up or go through the courts. As I have never been through the courts befor for anything in my life, this is a little daunting so am asking what would be the best action ?
Thanks in advance
Oh and reading into the noise regulations for vehicles there seems to be a load of confusion as to what it legal and what isn't. If my car was a JDM (imported) car, not a UK spec car, I would be allowed 99dB rather than 82dB (According to Norfolk Police)
The car is a UK spec 1996 Toyota Celica 2.0 GT with twin rear pipes.
Anyway back to the local station I go where they set up their test. They ask me what the Red line is on the car and does the rev counter work. I say it's working fine and it is a 7K red line.
They look up on their form and ask me to hold the revs at 3/4 throttle (5250 RPM) for 10 seconds while they take a reading. This they did 3 times on each side of the car.
They then tell me that the average dB reading is 94.1dB. The legal limit is meant to be 82dB and they prosecute above 90
Anyway They give me a £30 fine and tell me to get the car quieter. No re-test, no producer just told to watch my back as the next time it would be court, points and possibly the car crushed
The following day I talk to the type approval and legal guys at work. they said that the Police have it wrong. I then look into the ISO5130 which they readily quote on their paperwork. After some careful reading I find the section about the RPM measurements and yes, the Police have it totally wrong.
Remeber they asked me to have the car sitting at 5250RPM.... well ISO 5130 section 6.4.3 states that:
The target engine speed for category M & N vehicles shall be :
75% of the rated engine speed for vehicles with max power equal to or less than 5000Rpm
3750 RPM for vehicles with a rated max power between 5000 but less that 7500 RPM (this is the category my vehicle falls into)
50% of the engine speed for vehicles with a max power rating over 7500 RPM
They tested 1500RPM higher than the ISO Spec says.
I querey this with the Police, and they say that they will look into it, but if the PC who did the test feels that it was done correctly then the £30 fine stands.
I tell them that their paperwork is incorrect, but they tell me that they are not looking into that, just that the test was done to their procedure and now I have to pay the £30 fine or go to court.
I have 10 days now to either pay up or go through the courts. As I have never been through the courts befor for anything in my life, this is a little daunting so am asking what would be the best action ?
Thanks in advance
Oh and reading into the noise regulations for vehicles there seems to be a load of confusion as to what it legal and what isn't. If my car was a JDM (imported) car, not a UK spec car, I would be allowed 99dB rather than 82dB (According to Norfolk Police)
This is where the confusion starts. SVA tests (Single Vehicle Authorization) are done the same was as ISO5130. ie the Microphone is 20Cm from the ground, 50cm away from the exhaust and 45° to the end pipe. This is meant to be for the 82dB UK or 99dB import cars.
The 74dB (As I have been informed by the type approval guys at work)comes from the Drive by tests which are done on a Test Track, the Mic is 7.5m away from the center line of the vehicle and the vehicle is driven at 30mph then hard acceleration to 50Mph the complete vehicle noise is taken. Engine, tyres, wind, exhaust.
This test could not possibly be checked by the Police as they do not have the finances or infrastructure to cope with a test track at every police station.
Some Police forces quote 82Db, some 80, some 74. None of them actually know what the limit is. Even the ISO5130 only tells them how to conduct the test, not what results are deemed to be satisfactory or not.
The 74dB (As I have been informed by the type approval guys at work)comes from the Drive by tests which are done on a Test Track, the Mic is 7.5m away from the center line of the vehicle and the vehicle is driven at 30mph then hard acceleration to 50Mph the complete vehicle noise is taken. Engine, tyres, wind, exhaust.
This test could not possibly be checked by the Police as they do not have the finances or infrastructure to cope with a test track at every police station.
Some Police forces quote 82Db, some 80, some 74. None of them actually know what the limit is. Even the ISO5130 only tells them how to conduct the test, not what results are deemed to be satisfactory or not.
That surprised me when the Pc said "it looked noisy".
This whole Exhaust noise issue is a really confusing area. How can a UK car be 82dB but an import be 99dB ? and that is clearly printed on the bottom of the Police form.
The calibration of the noise meter was done before and after the test and I did ask about calibration certificates which the PC showed me the relevant paperwork, (I think they are getting wise to that question now).
The one thing I regret not doing is asking for a benchmark test to be done on their vehicle at time so I could have a comparison. When I asked for a test to be witnessed later I was told that unless I had good reason to suspect a defective police car and had their reg. No. and go through the correct channels then I would not be shown the test. Their normal get-out clause.
This whole Exhaust noise issue is a really confusing area. How can a UK car be 82dB but an import be 99dB ? and that is clearly printed on the bottom of the Police form.
The calibration of the noise meter was done before and after the test and I did ask about calibration certificates which the PC showed me the relevant paperwork, (I think they are getting wise to that question now).
The one thing I regret not doing is asking for a benchmark test to be done on their vehicle at time so I could have a comparison. When I asked for a test to be witnessed later I was told that unless I had good reason to suspect a defective police car and had their reg. No. and go through the correct channels then I would not be shown the test. Their normal get-out clause.
OOh, nice to get an ex-law enforcement persons view on things. I know about the S59's as one of my son's got issued with a couple when on his moped. 1st on = slap on the wrist, 2nd one cost him £150 + £10 to get back from an impound. He was not happy. I believe they are marked for both rider/driver and vehicle, so if you sell the vehicle on which has a s59 marker on it, if the new owner gets their first one, the vehicle has a 2nd one marked on it and it gets impounded.
Anyway that's another story.
Just to add to the original Noise test info. I had a phone app. for a noise meter which I ran while the Police were doing their test, It too read within about 1 or 2 dB of the Police reading.
When I got home I did the same test on my wife's 2.0l Passat estate. It read 90 dB at the 3/4 throttle setting as asked for by the Police. My son's Seat Leon 1.4 read 88dB amd my other son's VW Golf 1.4 read 87dB. All 3 cars have OEM exhaust systems and are totally standard.
At the 3750 RPM mark their cars were all around the 78 to 80dB mark. My Celica was about 85/86dB, above the magical 82dB mark that the Police set, but below the 90dB mark the prosecute at.
Anyway that's another story.
Just to add to the original Noise test info. I had a phone app. for a noise meter which I ran while the Police were doing their test, It too read within about 1 or 2 dB of the Police reading.
When I got home I did the same test on my wife's 2.0l Passat estate. It read 90 dB at the 3/4 throttle setting as asked for by the Police. My son's Seat Leon 1.4 read 88dB amd my other son's VW Golf 1.4 read 87dB. All 3 cars have OEM exhaust systems and are totally standard.
At the 3750 RPM mark their cars were all around the 78 to 80dB mark. My Celica was about 85/86dB, above the magical 82dB mark that the Police set, but below the 90dB mark the prosecute at.
They wouldn't care, the ISO spec gives a level of 3/4 revs for a vehicle which has max power at 5000RPM. Any vehicle which is revved for a prolonged period with no load can cause damage. Also, my son had a 1.0l Seat Ibiza as his first car, that didn't have a rev counter, so how would they test that ?
As the test was conducted with the microphone 20cm from the ground as designated by ISO5130. I asked about modern motorcycles with hi-rise pipes. Their answer was "I thought you might ask that, frankly I don't know how to test them"
So many unanswered questions ?
As the test was conducted with the microphone 20cm from the ground as designated by ISO5130. I asked about modern motorcycles with hi-rise pipes. Their answer was "I thought you might ask that, frankly I don't know how to test them"
So many unanswered questions ?
SMGB said:
"600m from home," "looks noisy". This stinks,do you have an issue with one of your neighbours or is the Plod related to one of them? Someone had complained + told them when you leave home and they were waiting.
Both of my MGs have stainless straight throughs and we often leave at stupid o clock to go on events during the season. I drive them as quietly as possible, several young families here. We have never ever had a problem.
There are some intelligent BiB on here, their toes must curl when they read threads like this.
No, not a problem with the neighbours, The Police were going in the opposite direction then did a U turn and followed me for about a mile. 30mph limit. When stopped I asked what the problem was, they said my driving was very good, but the exhausts looked loud. !!!Both of my MGs have stainless straight throughs and we often leave at stupid o clock to go on events during the season. I drive them as quietly as possible, several young families here. We have never ever had a problem.
There are some intelligent BiB on here, their toes must curl when they read threads like this.
Apparently one of my friends got pulled for the same offence in his Corrola a month earlier.The police officer doing the test was actually being tested at the same time. The dB meter was a new piece of kit the Force had aquired that month, so he was told. His Corrola kicked out 87dB and that was with a Std exhaust. Slap on the wrists as itm was below the "unwritten" 90dB prosecution limit.
I presume as it was a new piece of kit, they need to justify it's use. I have no problem with that, just need to do the test correctly or read the specification as laid down by the ISO standard.
I presume as it was a new piece of kit, they need to justify it's use. I have no problem with that, just need to do the test correctly or read the specification as laid down by the ISO standard.
simoid said:
I am, perhaps wrongly, assuming that there is some sort of paperwork along the lines of "car tested @ x RPM gave readings of a b & c decibels...
I am also assuming, perhaps wrongly, that the OP would be obliged to introduce "reasonable doubt" that the alleged offense was committed.
You are correct, The car was checked at 5250RPM and gave a dB reading of 94.1dB However ISO 5130 which the Police Quote on their paperwork says that : (Taken from ISO5130)I am also assuming, perhaps wrongly, that the OP would be obliged to introduce "reasonable doubt" that the alleged offense was committed.
6.4.3 Vehicles of category M, N
The target engine speed shall be:
- 75 % of the rated engine speed, S, for vehicles with S equal to or less than 5000 min,
- 3750 min - for vehicles with a rated engine speed 5000 to 7500 min,
- 50 % of the rated engine speed, S, for vehicles with S equal to or greater than 7500 min,
with a tolerance of ± 5 %.
Where as:
3.2
vehicle category M
power-driven vehicles having at least four wheels and used for the carriage of passengers
3.3
vehicle category N
power-driven vehicles having at least four wheels and used for the carriage of goods
3.4
rated engine speed
S
engine speed at which the engine develops its rated maximum net power as stated by the manufacturer.
The Police form just has a blanket statement of "test at 3/4 power"
So my little Celica has it's red line at 7000RPM with max power at 6800RPM, so should fall into the second line of paragraph 6.4.3
therefore they (The Police) tested the vehicle 1500RPM too high.
I am going to consult my local CAB to see what they say then probably go down the "see you in court" route.
I have written to the local Police HQ, and advised them of their error, they waited for over a month to get back to me saying that the Officer conducted the test correctly in accordance to ther (Norfolk Constabulary) test procedures so the FPN stands, they were not looking into the fact that their test contradicts the ISO standard.
I have said on every single correspondance with them that I am more than happy to have my vehicle re-checked, If it is still over 90dB then fair enough.
I had the exhaust system checked at a local exhaust specialist who deal with the system I have on. They noise checked it and it was 86.7dB at 5250RPM and 83.4dB at 3750RPM, though the testing ground they had differed from the Police one as there were buildings within 3M of the exhaust pipe. (which would possibly make it worse)
I have said on every single correspondance with them that I am more than happy to have my vehicle re-checked, If it is still over 90dB then fair enough.
I had the exhaust system checked at a local exhaust specialist who deal with the system I have on. They noise checked it and it was 86.7dB at 5250RPM and 83.4dB at 3750RPM, though the testing ground they had differed from the Police one as there were buildings within 3M of the exhaust pipe. (which would possibly make it worse)
For the record, the car has a Powerflow system. Original Cat with a 300mm centre box and twin rear boxes. Yes it's not original, but how many sports cars out there have their original systems. More to the point how many Saxo's, Corsa's Fiesta's etc out there have "BigBoy" exhausts and 1 million Gigawatt Subs booming out day and night with out anything being done.
The exhaust has been on my car for about 6 or 7 years with no issues before. It has been declared to my insurance company with no issues. How many of these Saxo's etc. have had their systems declared to the insurance companies ?
The exhaust has been on my car for about 6 or 7 years with no issues before. It has been declared to my insurance company with no issues. How many of these Saxo's etc. have had their systems declared to the insurance companies ?
I know but it just felt better putting it "to paper" so to speak. I am just annoyed that I was stopped on a sunny Sunday afternoon buy two Police traffic officers who had a new toy to play with. I wasn't speeding, I wasn't driving like a t**t. Just pootling around in my mid-life chrisis car which I love & cherish.
An over weight, middle aged family bloke just minding his own business.
as you can probably guess it's really beginning to grind on me now
An over weight, middle aged family bloke just minding his own business.
as you can probably guess it's really beginning to grind on me now
Red Devil said:
I would be surprised if the CAB have anyone with the required expertise to advise on this.
The magistrates who will be trying the case probably won't have a clue either, so will need to rely on the legal expertise/advice of the Clerk of the Court.
Your case rests soley on an incorrect test being applied by the BiB. The question is, do you have documentary evidence that they did so which you can put before the bench? Having the right paperwork is everything when relying on a technical defence.
Be aware that you are effectively challenging their 'procedure', which they claim to be correct. They won't take that lying down.
Yes, I have their (Norfolk Police) paperwork which quotes noise test done in accordance with ISO5130 and have a copy of the latest ISO5130 which differs from the police form. As I have said earlier, they checked my car at 5250 RPM, ISO5130 states the test to be done ar 3750RPM. If my maths is correct, that is 1500RPM lower than the Police checked it at THAT is what I am arguing aboutThe magistrates who will be trying the case probably won't have a clue either, so will need to rely on the legal expertise/advice of the Clerk of the Court.
Your case rests soley on an incorrect test being applied by the BiB. The question is, do you have documentary evidence that they did so which you can put before the bench? Having the right paperwork is everything when relying on a technical defence.
Be aware that you are effectively challenging their 'procedure', which they claim to be correct. They won't take that lying down.
I have no idea about the "E" markings. The whole issue is not whether the exhaust is legal or illegal. It's about the Police issuing FPN's in information which is incorrect.
Anyway, the local CAB put me in touch with a Solicitor who had a look through all my paperwork and said that, "It's clear as day that the Police have dropped a clanger" He also said that" the chances were if you opt for the magistrates court then the Police woupld in all probablity drop the case as they have, so far not looked deep enough into their paperwork contradiciting the ISO spec they quote".
So looking positive for a result, but who knows !!!
Anyway, the local CAB put me in touch with a Solicitor who had a look through all my paperwork and said that, "It's clear as day that the Police have dropped a clanger" He also said that" the chances were if you opt for the magistrates court then the Police woupld in all probablity drop the case as they have, so far not looked deep enough into their paperwork contradiciting the ISO spec they quote".
So looking positive for a result, but who knows !!!
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