This standard specifies the classification of requirements and parameters of the speed control system of reciprocating internal combustion engines, as well as the terms and definitions of typical engine speeds. Separate requirements may be made for special purpose engines if necessary. This standard applies to land, railway traction and marine reciprocating internal combustion engines, but does not include driving road construction machinery, earth moving machinery, agricultural and industrial tractors, road vehicles and aviation engines, and does not include self-adjusting engines and only requires the highest engine speed or maximum fuel delivery. This standard specifies the requirements for compression ignition engines (diesel engines). Special requirements may apply to spark ignition engines and dual fuel engines. Note 1 See GB/T 2820.2 and GB/T 2820.5 for the performance and parameters applicable to the speed control system of reciprocating internal combustion engine alternator set. 2 See GB/T 6072.6 for terms and definitions of typical engine speeds related to overspeed protection devices.