On December 16, 1997, the European Parliament and the Council of the European Union issued Directive 97/68/EC on the measurement of gas and particulate emissions from internal combustion engines for non road use, which set emission requirements for compression ignition engines for non road use. The directive stipulates that from December 31, 1998, non road compression ignition engines with a power greater than 37 kW will be subject to mandatory Stage I emission requirements in stages. Starting from December 31, 2000, Phase II emission requirements will be mandatory for non road compression ignition engines with a power greater than 18 kW in stages.

On August 17, 2001 and December 9, 2002, directives 2001/63/EC and 2002/88/EC were respectively issued for expansion and revision, and were compiled into a unified "CONSLig 1997L0068" in February 2003. The directive has added emission regulations for non road ignition engines. Starting from August 1, 2004, non road spark ignition engines with a power of ≤ 19kW are required to comply with Stage I and II emission standards.

On April 21, 2004, the European Parliament and the Council of the European Union issued Directive 2004/26/EC, which further expanded Directive 97/68/EC to cover compression ignition engines used in inland ships, rail cars, and railway locomotives. At the same time, emission standards and implementation dates for non road compression ignition engines in stages IIIA, IIIB, and IV were announced. The directive stipulates that from June 30, 2005, the emission requirements for Stage III and IV will be enforced in stages based on the power range and actual use of the engine. For example, the implementation date of non constant speed compression ignition engines (19kW ≤ power<37kW) was December 31, 2005.