scope:

This European Standard specifies a test method for the quantitative determination of the indicated cetane number (ICN) of middle distillate fuels and blending components, intended for use in compression ignition engines. The test method utilizes a constant volume combustion chamber with direct fuel injection into heated compressed air. Calibration of the apparatus using blends of primary reference materials over a scale of 0 to 100 enables fuel ignition delays, measured from the resulting pressure increase, to report ICN results. This European Standard is applicable to middle distillate fuels of both petroleum and non-petroleum origin, hydrocarbon oils, oil-sands based fuels, blending components, fatty acid methyl esters (FAME), blends of fuel containing biodiesel material, diesel fuel oils containing cetane number improver additives, low-sulfur diesel fuel oils, aviation turbine fuels and polyoxymethylene dimethyl ether (OME). However, users applying this standard especially to unconventional distillate fuels are warned that the relationship between cetane number and combustion behaviour in real engines is not yet fully understood.