The PONA number is an index for oil components used to determine the paraffins (P), olefins (O), naphthenes (N) and aromatics (A) content[1] of FCC (fluid catalytic cracking) and coker (visbreaker) gasoline.
The PONA number plays a significant role in determining the quality of naphtha. Various grades of naphtha are produced depending on the PONA specifications, such as 60/15, 65/12, 70/10, etc. The first number represents the minimum allowable total parafins percentage and the second number specifies the maximum allowable aromatics percentage. It also determines the price of naphtha in international markets.