This method is for determining total arsenic in petroleum naphthas by Hydride Generation-Atomic Absorption Spectroscopy (HG-AAS). The method is quantitative to one mass-ppb (ng/g) when a 100-g sample is used. This method yields results equivalent to, and can be used in place of, UOP Method 296. The method was validated by spiking with triphenylarsine, As(C6H5)3; for which 100% recovery was obtained at the 80 mass-ppb level.