D976 CCI- CALCULATED CETANE INDEX OF DISTILLATE FUELS
The cetane index is a calculated quantity that is intended to approximate the cetane number. It is much cheaper to determine than the engine-based cetane number but its accuracy is limited to the type of fuel on which it is based. It generally does not provide an accurate indication of cetane number if the fuel contains cetane improving additives or for non-petroleum-based alternative fuels.
D4737 CCI- CALCULATED CETANE INDEX OF DISTILLATE FUELS
The Calculated Cetane Index by Four Variable Equation is useful for estimating Cetane number when test engine is not available for determining this property directly and when Cetane improver is not used. It may be conveniently employed for estimating Centane number when quantity of sample available is too small for an engine rating.