Maximum design earthquake. The earthquake selected for design or evaluation of the structure. This earthquake would generate the most critical ground motions for evaluation of the seismic performance of the structure among those loadings to which the structure might be exposed. For example, if a site were assigned MCEs for two separate sources, the MCE which would be expected to generate the most severe ground motions would be the maximum design earthquake. The response of the structure to specific ground motion parameters (frequency, duration, etc.) needs to be considered in specifying this event. In certain cases, more than one maximum design earthquake may be specified to reflect the differing response of various components of the structure to earthquake loading.