The STIR refers to first and second redundant systems to account for assets with two layers of redundancy as a way to manage risk (e.g., a battery storage system and a generator). These systems are modeled as independent with the second redundant system only being used if the first redundant system fails. For each critical asset, select which redundant system(s) can supply the energy or water resource(s) necessary for that asset to function in the event of a disruption to the primary supply. If the critical asset does not have an associated redundant system, then select “none”.