Cetane

The cetane number is an indicator of the combustion speed of diesel fuel and the compression needed for ignition. Diesel with a lower cetane number provokes ignition delays and requires more time for the combustion process to be completed. In other words, higher cetane numbers indicate better ignition quality. Therefore, diesel with a higher cetane number is preferred by engine makers as it influences an engine’s efficiency.

The regulatory limit for the Cetane Index of 48 and the regulatory limit for the Cetane Number of 51 was met for the average of samples taken under the SGS Worldwide Fuel Survey (WWFS) in all years except in 2012-2014 (cetane number only).

The figure below shows the average cetane index and number of diesel samples in 2011-2021.