[Grease Monkey]

Cribbed from the SVA Manual....


Procedure and Standards

1. Check the exhaust system is complete, is fitted with a silencer and is secure to the vehicle. NOTE: The following assessment must be completed even in cases where the exhaust system is holed/leaking due to deterioration.

2. Position the vehicle on an unobstructed test site (concrete or asphalt) which covers a rectangular area the sides of which are at least 3 metres from the vehicle sides, front and rear. Ensure the engine is at normal operating temperature. Using a sound level meter of ‘Type 1’ (as defined in BSEN 5969 or IEC651) to the manufacturers instructions, carry out a static noise check. NOTE: This check may be carried out following the emission test. Place the microphone

• at the height of the exhaust outlet, or a height of 200mm, whichever is the higher
• at an angle of 45° to the exhaust outlet in the direction which gives the greatest possible distance between it and the vehicle contour
• at a distance of 500mm from the exhaust outlet.

NOTE: If the exhaust has several outlets which are not more than 300mm apart and which are connected to the same silencer, the microphone must face the outlet closest to the vehicle contour or the highest above the ground. In all other cases, separate measurements must be taken, the highest recorded being the test value.

Run the engine at a constant speed of 3/4 of its maximum power speed eg. the speed at which maximum power is produced is 6,000 rpm, therefore the test is conducted at 4,500 rpm. Check the level of sound emitted. NOTE: Where the engine maximum power speed is not available, the test may be carried out at 2/3 engine maximum design speed.

Reason for Failure

1. An exhaust system

• incomplete
• not fitted with a silencer
• mounting or component insecure
• mounting of inadequate strength to support the weight of the system.

2. The measured sound level is more than 101 db(A).