Measurement of errors. The measurement of errors on installation and during use shall be carried out under the following conditions, which are to be regarded as constituting standard test conditions: vehicle unladen, in normal running order, tyre pressures in accordance with the manufacturer's instructions, tyre wear within the limits allowed by law, movement of the vehicle: the vehicle must proceed, driven by its own engine, in a straight line and on a level surface, at a speed of 50 ± 5 km/h; provided that it is of comparable accuracy, the test may also be carried out on an appropriate test bench.
