78. Concerning the diesel fuels used for the auxiliary and main propulsion diesel engines on-board the offshore supply vessel to which you are assigned, what fuel property is directly a measure of the ignition quality of the fuel?

Cetane rating directly measures the ignition quality of diesel fuel. It indicates the fuel's ignition delay and is a standard measure of its ability to ignite smoothly in a diesel engine; viscosity, heating value, and density do not reflect this property.