Positioning and preparation of the vehicle. The vehicle shall be located in the centre part of the test area with the gear selector in neutral position and the clutch engaged. If the design of the vehicle does not allow this, the vehicle shall be tested in conformity with the manufacturer's prescriptions for stationary engine testing. Before each series of measurements, the engine shall be brought to its normal operating condition, as specified by the manufacturer. If the vehicle is fitted with fan(s) having an automatic actuating mechanism, this system shall not be interfered with during the sound level measurements. The engine hood or compartment cover, if so fitted, shall be closed.
