A factor that reflects the amount of ozone depletion caused by a substance, on a mass per kilogram basis, as compared to chlorofluorocarbon-11 (CFC-11). Such factor is based upon the substance's atmospheric life time, the molecular weight of bromine and chlorine, and the substance's ability to be photolytically disassociated, and upon other factors determined to be an accurate measure of relative ozone depletion potential. (Source: GEMET/ LEE)