Australian Off Road Commission Communiqué

1.                 PREAMBLE

The Off Road Commission recently approved in principle changes to the 2011 Off Road Standing Regulations relating to Noise measurement.

Representatives of the Commission recently conducted tests at a State level Off Road event whereby it is proposed that a static test be implemented in 2011. This is in an effort to offer a more consistent test and one that all competitors will be able to replicate easily in order to ensure compliance.

2.                 NOISE TESTING FOR THIS YEAR

Due to the proposed implementation of a new noise testing procedure in 2011, there will be no official noise testing carried out at the Griffith round of the 2010 AORC, competitors will, however, be required to have their vehicles noise level checked unofficially by the AORC Technical Commissioner over the weekend.

All cars with log book entries made prior to 1^st July 2010 with regards to exceeding allowable emitted noise will be granted an amnesty on those entries.

The Commission proposes that the remainder of 2010 be an information gathering period whereby testing of the proposed static test will be conducted. This will allow the Commission time to ensure that the implemented procedure is consistent and easy to replicate for all competitors.

3.                 NOISE TESTING IN 2011

After trialling the static test for the remaining Championship events in 2010 the Commission propose to add regulations enacting the static type test as tested. The Commission propose the following to be added to the 2011 CAMS Manual of Motor Sport to replace 4.5 Noise as found within the Off Road Standing Regulations.

To add the following to the Off Road Standing Regulations of the 2011 CAMS Manual of Motor Sport;

4.5 Noise:

(i)Each car will be subjected to a noise emission test at least once every two years or at the discretion of the Technical Commissioner or Chief Scrutineer of an event. The maximum noise emission permitted from any vehicle is 98dB(A).

Note: Individual events may impose more stringent limits in order to comply with local requirements.

(ii) Each car with a log book entry made prior to 1^st July 2010 with regards to exceeding allowable emitted noise will be granted an amnesty on that entry.

(iii)Method of Measurement of Emitted Noise

A. SOUND LEVEL METER

(i) is a Type 2 Meter, tested to the relevant clauses of AS IEC 61672.2-2004;

(ii) must be used on FAST dynamic characteristic;

(iii) must be used on A weighting network;

(iv) must be calibrated at bi-annually.

B. TEST SITE

(i) must be in the open air;

(ii) must be substantially level and covered with concrete, asphalt or other similar hard material providing acoustic reflection;

(iii) must consist of an area bounded by a rectangle having sides at least 6m from the outline of the vehicle under test;

(iv) must contain no objects other than the vehicle and the sound level meter operator.

C. MICROPHONE POSITION

(i) must be equal to the height of the geometric centre of the orifice of the exhaust outlet, but not less than 200mm above the ground;

(ii) must be located 3000mm (±100mm) from the geometric centre of the orifice at the exhaust outlet;

(iii) must be at an angle of 45° (±10°) from the direction of travel of the vehicle at the side nearest the orifice of the exhaust outlet;

 (iv) for a vehicle fitted with two or more exhaust outlets spaced more than 300mm apart or connected to separate silencers, each exhaust outlet shall be treated separately as if it were the only one.

D. MEASUREMENT METHOD

At normal operating temperature the engine shall be brought to:

(iv) If the car measures over 98dB(A) the car shall not be permitted to contest another event until such time as it has been tested again and found to be compliant.

The Commission invites feedback to the proposed amendment to the Noise regulations.

Please provide feedback to offroad@cams.com.au .