Dilute concentrations of 1,1,1-trichloroethane (TCA) in air were decomposed in an electron beam generated plasma reactor. The energy required for high levels of TCA decomposition (greater than 90%) was determined as a function of inlet concentration. For 99% decomposition of TCA, epsilon approximate to 300 eV/molecule at 250 ppm inlet concentration, and epsilon approximate to 100 eV/molecule at 3000 ppm. A radical reaction mechanism is proposed which accounts for the formation of the major reaction products : 1,1-dichloroethylene, HCl, chloroacetylchloride, CO2, and COCl2. A model is derived based on first-order inhibited kinetics; a fit of the data to the model shows that at high decomposition fractions, radical scavenging by reaction products is a significant inhibitor of TCA decomposition.