28.1 DEFINITIONS

28.1.1 ‘Component’ means one of the individual constituent parts whose assembly constitutes the ‘Noise Reduction System’.

28.1.1.1 These ‘Components’ are, in particular, the exhaust manifold, the exhaust piping, the expansion chamber, the silencer proper. If the engine intake is equipped with an air filter and the filter’s presence is essential to ensure observance of the prescribed sound level limits, the filter must be regarded as a ‘Component’ of the ‘Noise Reduction System’.

28.1.2 ‘Diesel Engine’ means an internal combustion engine which operates on the compression-ignition principle.

28.1.3 ‘Engine Speed at Maximum Power’ (‘ESMP’) means the speed at which the engine develops maximum power (r/min).

28.1.4 ‘Net Engine Power’ (‘NEP’) means the engine power expressed in kW (ECE) and measured:

28.1.4.1 for positive-ignition engines, by the method described in Annex 8 to UN ECE Regulation No 15 - “Emission of Gaseous Pollutants”:

28.1.4.2 for ‘Diesel Engines’, by the method described in Annex 10 to UN ECE Regulation No. 24 - “Diesel Engine Pollutant Emissions”,

28.1.5 ‘Noise Reduction System’ means a complete set of ‘Components’ necessary for limiting the noise made by a motor vehicle and its exhaust.

28.1.6 ‘Off-road Use’ means the type of use requiring a vehicle to have the special design features listed in the definition of ‘Off-road Passenger Vehicle’.

28.1.7 ‘Spark Ignition’ means positive ignition.