Supplement 1 to the 01 series of amendments - Date of entry into force : 31 January 2003 Supplement 2 to the 01 series of amendments - Date of entry into force : 12 August 2004 Uniform provisions concerning the approval of compression ignition ( C.I . ) engines to be installed in agricultural and forestry tractors and in non-road mobile machinery with regard to the emissions of pollutants by the engine REGULATION Page