This gas chromatographic method is for determining individualand total trace hydrocarbon impurities in olefin-free, high-puritybenzene. C8 and lower boiling paraffins, naphthenes, toluene, andC8 aromatics are determined. The lower limit of quantitation forany single component is 1 mg/kg (mass-ppm).

Benzene purity can also be determined by ASTM Method D4492,where the lower detection limit is 50 mg/kg per component. Althoughbenzene is not listed in their scopes, ASTM Methods D2360, D5917,and D7504 may also be used to measure impurities in benzene. All ofthese ASTM Methods determine the non-aromatics as a total whereasthis method also provides a distribution.