In this work partial safety factor to be adopted in the design of the isolators' displacement capacity have been analyzed. Reference values have been derived in order to meet the Near Collapse reliability target set in standard codes, by considering the same theoretical framework used to derive partial factors for displacement-based design of structural members in fixed-base structures, for the second-generation Eurocode 8. The obtained values have been numerically validated through the analyses of the outcomes multiple-stripe inelastic response history analyses, capable of considering the full range of phenomena occurring at higher than design seismic intensities, including device and super-structure damage.