In this article, Part II of the series, we report a detail study on stabilization of EPDM vulcanizates in gamma-radiation environment. The special additives (antirads), namely pyrene (Py), brominated acenaphthene (BrAc), poly(acenaphthene sulfide) (PAcSu) and poly(pyrene sulfide) (PPvSu) were used for the stabilization studies. The efficiency of these antirads for EPDM had been monitored by the means of electrical resistivity, wide-angle X-ray diffraction, and mechanical properties. The stabilization of EPDM to withstand 200 Mrads of gamma radiation in air environment is achieved.