Car Exhaust Noise

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Monkey boy 1

Original Poster:

2,063 posts

230 months

Saturday 6th October 2012
quotequote all
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 90frown

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 eek


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)confused

monkey11477

128 posts

201 months

Saturday 6th October 2012
quotequote all
Have you tested your cars dB at the correct rpm?

Monkey boy 1

Original Poster:

2,063 posts

230 months

Saturday 6th October 2012
quotequote all
Had a test done at a local exhaust specialist and it was around 80 to 84 dB but not in the same surroundings. buildings close to the vehicle. ISO5130 states there must be a 3m clear zone around the vehicle.

Toltec

7,159 posts

222 months

Saturday 6th October 2012
quotequote all
From http://www.direct.gov.uk/en/TravelAndTransport/Usi...


[quote]Road vehicles
The noise levels for cars used on a public road is 74 decibel (dB(A)). Most vehicles produce lower levels.
Off-road vehicles and direct injection diesels are allowed to be 1 dB(A) louder. These allowances can be combined, so the limit for an off-road vehicle with a direct injection diesel engine is 76 dB(A).
It’s illegal to modify the exhaust system to make a vehicle noisier after it has been ‘type approved’ (checked it meets environmental and safety standards). The police can also take action if your vehicle's silencer doesn’t work or if you’re driving in a way that creates too much noise.
[/quote]

Does not appear to be anything about stopping you for having an exhaust that looks noisey.

Interested to know how this pans out OP and hope it ends well.

Monkey boy 1

Original Poster:

2,063 posts

230 months

Saturday 6th October 2012
quotequote all
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.

Toltec

7,159 posts

222 months

Saturday 6th October 2012
quotequote all
Just noticed what you do for a living on your profile, I used to work in the field too.

Did you manage not to mention calibration certificates and traceability to the PCS?

Must admit I thought even aftermarket exhausts were OK if 'E' marked and not modified. I am pretty sure my completely standard Smart would be over 82dB, might have to see if I can get it checked just out of interest.


streaky

19,311 posts

248 months

Sunday 7th October 2012
quotequote all
This thread and others might be of interest, particularly the post about ProDrive exhausts on Scoobies. The government website cited above is short on detail and therefore overall accuracy [no surprise there, then].

Streaky

blueg33

35,590 posts

223 months

Sunday 7th October 2012
quotequote all
I don't get this

1. How can an exhaust "look" noisy, surely it can only sound noisy

2. I dont get the test either, there are plenty of type approved cars, TVR's Ferrrari's Lambo's AMG mercs etc that are louder than 84db with those tests. If its type approved and un-modified how can it be illegal?

Monkey boy 1

Original Poster:

2,063 posts

230 months

Sunday 7th October 2012
quotequote all
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.

wizzbilly

955 posts

192 months

Sunday 7th October 2012
quotequote all
More utter rubbish from pc plod LOOKS NOISEY wtf is this world coming to .

Have heard of this issue before and i no of a freind of mine where police have tried to prosicute for been to loud .

front exit exhaust out front bumper of a honda civic turbo is loud but as far as am aware never actually managed to make a conviction stick ,

the reason police choose to try do stuff like this as revenue they no your not going to want to go to court for sake of £30 as will cost you more in solicters fees so basicly choose as easy target .


if you got free solicters and had drug addiction they would of ignored you but sounds to me like yet again another jobsworth .

if you can prove the test was done incorectly i would take it to court and make the jam sandwhich look a complete tool .

triumphkryten

369 posts

162 months

Sunday 7th October 2012
quotequote all
I know my missus would tell me that I was being anal and OTT, but I would be bloody outraged over this, and would probably spend a lot of money that could have better uses to take it further... It boils my piss when a copper will take you back to the station, incorrectly carry out a test on a flimsy pretext of "looking loud" instead of being out on the street and catching the people that find talking on their phone more important than how, and towards whom they are driving.
My guess is they got a new dB meter and wanted to give it a try on someone they could get an easy pull/conviction on.
Your biggest problem is proving they carried the test out incorrectly to the satisfaction of a magistrate... If you think you can, good luck and let us know how you get on...



Edited by triumphkryten on Sunday 7th October 12:54

Clivew

348 posts

174 months

Sunday 7th October 2012
quotequote all
Monkey boy 1 said:
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.
SVA quoted 104 dbA at 3/4 max engine output. This has now been superceded by the IVA and it quotes 99dbA max at 3/4 max power engine speed. Does this mean that if you car passes the noise limit at IVA you can be stopped at the gates by the police and charged with an over-loud exhaust? Seems crazy to me

Futuramic

1,763 posts

204 months

Sunday 7th October 2012
quotequote all
Yet another reason I left the police; prosecuting for mealy mouthed rubbish that serves no purpose. I don't think anyone will be sleeping more soundly tonight because your Toyota has gained a ticket.

I know nothing about noise testing so can't help you there; but I can tell you that the policeman was lying when he mentioned what could happen in future.

You received a £30 FPN, for a non-endorsable offence. The nice policeman told you that the car could be confiscated or points given if caught again. This is complete nonsense. A non-endorsable offence is exactly that; one can be prosecuted any number of times and the police cannot issue a harsher punishment. If I recall, when a driver admits an offence the police are supposed to offer an FPN. If that is paid then the matter is concluded. They cannot invent another sentence because they don't like the look of you.

It's a classic tactic to scare people who have committed a minor motoring infringement. "Next time you'll get points" is an oft quoted phrase. In order to confiscate the car they'd need to issue a S59 warning, which it appears they haven't, and then catch you again and issue another one. Potentially you've got three goes before anything serious happens. Or they could try and charge you with vehicle based harassment; which I would like to see them try.

Monkey boy 1

Original Poster:

2,063 posts

230 months

Sunday 7th October 2012
quotequote all
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.

daz3210

5,000 posts

239 months

Sunday 7th October 2012
quotequote all
How would they test a diesel? As I understand it it can be dangerous to the engine to over rev without load (I was told not to by my driving instructor), or have modern diesels changed?

SMGB

790 posts

138 months

Sunday 7th October 2012
quotequote all
"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.

Monkey boy 1

Original Poster:

2,063 posts

230 months

Sunday 7th October 2012
quotequote all
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 ?

MrBrightSi

2,912 posts

169 months

Sunday 7th October 2012
quotequote all
I used to run the williams with no silenecers and that was LOUD. It never got beans in crowded places at night, but was sometimes fun to scare people (Utterly childish and pathetic i know)

I cannot beleive you got a fine for this, surely if this kind of act is allowed to continue we'll be living in some sort of orwellian nightmare soon enough.

wizzbilly

955 posts

192 months

Sunday 7th October 2012
quotequote all
Futuramic said:
Yet another reason I left the police; prosecuting for mealy mouthed rubbish that serves no purpose. I don't think anyone will be sleeping more soundly tonight because your Toyota has gained a ticket.

I know nothing about noise testing so can't help you there; but I can tell you that the policeman was lying when he mentioned what could happen in future.

You received a £30 FPN, for a non-endorsable offence. The nice policeman told you that the car could be confiscated or points given if caught again. This is complete nonsense. A non-endorsable offence is exactly that; one can be prosecuted any number of times and the police cannot issue a harsher punishment. If I recall, when a driver admits an offence the police are supposed to offer an FPN. If that is paid then the matter is concluded. They cannot invent another sentence because they don't like the look of you.

It's a classic tactic to scare people who have committed a minor motoring infringement. "Next time you'll get points" is an oft quoted phrase. In order to confiscate the car they'd need to issue a S59 warning, which it appears they haven't, and then catch you again and issue another one. Potentially you've got three goes before anything serious happens. Or they could try and charge you with vehicle based harassment; which I would like to see them try.
Good post think most dare i say older generation are leaving the force for such reasons , 2 of my family members left on pretty much the same reasons was no longer about policing , what happened to the good old days when officer would tell you to bugger of home and give you a clip around the ear , this sure as hell worked better and gave them a lot more respect .

Monkey boy 1

Original Poster:

2,063 posts

230 months

Sunday 7th October 2012
quotequote all
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. !!!