A novel application of charged particle activation analysis is presented involving short irradiations of 1 sec coupled with the measurement of very short-lived nuclides. The case studied deals with the determination of sulfur using 32S(p, n)32Cl. This activation reaction features a high abundance target isotope and a product nuclide of very short half-life (300 msec) emitting high energy positrons. Counting was performed with a Cherenkov detector at the irradiation site immediately after bombardment. The experimental approach for optimizing the counting conditions is described and the activation curve for 32S(p, n)32Cl is given for proton energies up to 22.5 MeV. The sensitivity based on experimental data is estimated at ≈50≃g/cm2. The application of this technique to petroleum products with sulfur contents ranging from 3.18% to 0.72% is discussed.