Cetane numbers are tested using a special test engine and the existing engine was not made for residual fuels. For residual fuel oil two other empirical indexes are used: CCAI and Calculated Ignition Index (CII).
Cetane numbers are determined using a specialized test engine, and the existing engine was not designed for residual fuels. For residual fuel oil, two additional empirical indexes are used: the Corrected Cetane Index (CCAI) and the Calculated Ignition Index (CII).