ISO 20846:2004 specifies an ultraviolet fluorescence test method for the determination of the sulfur content of motor gasolines, including those containing up to 2,7 %(m/m) oxygen, and of diesel fuels, including those containing up to 5 % (V/V) fatty acid methylester (FAME), having sulfur contents in the range 3 mg/kg to 500 mg/kg. Other products may be analysed and other sulfur contents may be determined according to this test method, however, no precision data for products other than automotive fuels and for results outside the specified range have been established for ISO 20846:2004. Halogens interfere with this detection technique at concentrations above approximately 3 500 mg/kg.

Some process catalysts used in petroleum and chemical refining may be polluted when trace amounts of sulfur-bearing materials are contained in the feedstocks.This test method may be used to determine sulfur in process feeds and may also be used to control sulfur in effluents.