H 0504 Procedure - Loud Exhaust Offences
Number: H 0504
Date Published: 18 September 2023
Version 5 – September 2023
1.0 Summary of Changes
On its review there has been one amendment made:
- Section 3.5 - Departmental change from Casualty Reduction Section to Roads Policing, OPC.
2.0 What this Procedure is about
This procedure details the process to be undertaken when dealing with altered exhaust systems in relation to use of motor vehicles on a road. These offences are more commonly referred to as noisy exhausts.
Compliance with this procedure and any governing policy is mandatory.
3.0 Detail the Procedure
3.1 Legislation
Operation of this procedure relies on the use of 2 offences:
- Silencer/ exhaust system altered to increase noise – Reg. 54(2) The Road Vehicles (Construction & Use) Regulations 1986;
- Avoidance of excessive noise – Reg. 97 The Road Vehicles (Construction & Use) Regulations 1986
In summary, vehicle exhausts must not be altered or replaced in a manner which increases the noise above that emitted by the type approved exhaust fitted by the manufacturer.
In any case the sound emitted by an exhaust fitted to a standard car must not exceed 80dB. Some other vehicles, such as those with differing engine power e.g. HGVs, PCVs, motorcycles, etc. have higher limits up to 89dB. The second offence relates vehicles being used in a manner as to cause any
excessive noise which could have been avoided by the exercise of reasonable care by the driver. This may include revving engines, tyre noise and in some cases, audio equipment. The first offence is specific offence and should be used in most cases.
3.2 Identification of Offences
All new vehicles sold in this country comply with legal requirements in relation to exhaust noise and you cannot purchase one which has an exhaust louder than permitted. This includes cars which are traditionally marketed towards the ‘cruiser’ customer base such as ST, VXR and GT variations of popular models. However some dealers will offer a dealer fit option subsequent to manufacture of an exhaust which exceeds maximum levels there will be a clear disclaimer within the paperwork of ‘for track use only’ or ‘not for use on public roads’ etc. in such circumstances.
Initial identification will normally come from hearing a vehicle which has a noticeably loud exhaust above other road noise such as tyres and engines, especially if it is over a prolonged period.
Many after-market exhausts which are louder than permitted will be stamped with warnings however in practical terms this is only really relevant for motorcycles, which have exposed and accessible exhausts.
Before taking any action other than a verbal warning the exhaust should be tested using the NTI XL2 Audio Analyser. This device must be operated by a trained officer, in line with the manufacturer’s instructions and the data recorded on the appropriate Form T250.
Where no device or the sole reliance on the device is not appropriate, such as with motorcycles, it may be still be appropriate to proceed. In these circumstances officers should consider commenting on the following points:
- Warnings stamped on the exhaust; ‘Not for road use’, ‘track use only’ or similar;
- Observations relating to what could be heard and felt;
- Other indications the exhaust or silencer had been altered or replaced and thereby increasing the noise from the original fitted part;
- Impact on of the noise on the general surroundings i.e. natural reaction of those passing by.
3.3 Operating the NTI XL2 Audio Analyser
The device is not to be used for fully testing motorcycles – this is because the device will not only record the exhaust noise, but also pick up rattles, vibrations and other sounds from the engine and moving parts. However this should not prevent it being used to record an overall sound level which supported by officers evidence may be acceptable to the courts.
The NTI XL2 Audio Analyser is a type-approved device. Only trained and authorised officers should operate the devices and all tests should be carried out in line with the training.
It is not practical in an operational policing environment to fully comply with all requirements of the ISO standard 5130:2006 (Acoustics - Measurements of sound pressure level emitted by stationary road vehicles); however where we deviate from the ISO standard, it is not to the detriment of the driver. This is due to measurements being taken under the following conditions:
- Engine speed of 50% of maximum as displayed on the vehicle’s tachometer and not 75% as allowed by the standard;
- No allowance for the reduction in sensitivity of the microphone due to the wind screen cover;
- Readings are always rounded down to the nearest whole number whereas the standard allows rounding up or down;
- The lowest reading is used only never the highest or average readings.
This means we can provide a reliable minimum reading of noise emitted from the vehicle’s exhaust at the time. This will be representative of the disturbance it was causing.
3.4 Disposal of Offences
Where a vehicle is suspected of being driven on a road with an excessively loud exhaust the driver can be dealt with in the following ways:
- Verbal warning;
- Non-endorsable fixed penalty notice for the offence of ‘Silencer/ exhaust system altered to increase noise’ (RC86068) (£50);
- Non-endorsable fixed penalty notice for the offence of ‘Avoidance of excessive noise’ (RC86092) (£50).
For foreign drivers with no address suitable for service of summons a graduated fixed penalty notice/ roadside deposit may be issued in place of methods 2 and 3.
Where repeat offenders are identified then consideration should be given to the submission of a minor traffic process file for the most appropriate offence.
| Noise Reading | Disposal Ref. | Notes |
|---|---|---|
| 80 – 89 dB | 1 | This relates to motor vehicles with no more than 9 seats including driver’s seat. |
| >90 dB | 2 | This relates to motor vehicles with no more than 9 seats including driver’s seat. |
| No reading available | 2 or 3 | This will also include motorcycles where the reading cannot be relied upon on its own |
Where the NTI XL2 Audio Analyser device has been used and Form T250 completed there is no need to supply the driver with a copy. Where a FPN is used as a form of disposal the Form T250 should be attached to the FPN prior to submission.
The warning notice should be detached, completed and handed to the driver accompanied by a verbal explanation covering the key points contained within.
3.5 Ownership and Calibration of Audio Analysers
Devices are owned by the Head of Roads Policing and allocated as appropriate. The return and calibration of all devices is managed by the Roads Policing Support at Billericay.
4.0 Equality Impact Assessment
- EIA – September 2021
5.0 Risk Assessment
A number of generic and site-specific risk assessments are applicable and officers should familiarise themselves with these prior to carrying out any vehicle checks.
These include:
- Road Policing – general risk assessments – scroll down to Roads Policing risk Assessments
- Stop Checks – Persons & Vehicles
6.0 Consultation
The following have been consulted during the formulation of this document:
- Equality and Diversity Co-ordinator
- Health & Safety
- Equality of Services Manager
- PSD Superintendent
- Roads Policing Department, OPC
- Roads Policing Skills, EPC
7.0 Monitoring and Review
This procedure will be continuously monitored by the Commercial Vehicle Unit. This will ensure that the procedure remains accurate and compliant with both legislation and national or local drivers.
An annual review will be carried by the Specialist Support Sergeant, Roads Policing to ensure the procedure remains accurate and fit for purpose.
8.0 Governing Force policy.
Related Force policies or related procedures
- H 0100 Policy – Roads Policing
- H 0500 Policy – Education and Enforcement
- A 1000 Policy – Anti-Social Behaviour
8.1 Data Security
Essex Police have measures in place to protect the security of your data in accordance with our Information Management Policy – W 1000 Policy – Information Management.
8.2 Retention & Disposal of Records
Essex Police will hold data in accordance with our Records Review, Retention & Disposal Policy – W 1012 Procedure/SOP - Records Review, Retention and Disposal.
We will only hold data for as long as necessary for the purposes for which we collected. Victims/public should be reminded that Essex Police take the protection of personal data seriously as described in the privacy notice.
9.0 Other source documents, e.g. legislation, Authorised Professional Practice (APP), Force forms, partnership agreements (if applicable)
- Authorised Professional Practice – Roads Policing
- NTI XL2 Audio Analyser Operating Manual
- International standards ISO 5130:2007 and IEC 61672
- Road Vehicles (Construction & Use) Regulations 1986
- Form T250 – Vehicle Exhaust Sound Testing - Officers Notes
- Silencer/ exhaust system altered to increase noise – Reg. 54(2) The Road Vehicles (Construction & Use) Regulations 1986;
- Avoidance of excessive noise – Reg. 97 The Road Vehicles (Construction & Use) Regulations 1986