Sets out test methods for measuring the fuel consumption of petrol, diesel and LP gas-fuelled vehicles under controlled conditions simulating city driving conditions and highway driving conditions. Measurement of the fuel consumed is made either by analysis of the exhaust gases and evaluation of the amount of carbon in them in terms of the amount of carbon in unburnt fuel, or by direct measurement of the volume, or mass, of fuel consumed, since a comparable degree of accuracy may be obtained by each of these methods. Test fuel specifications are given.