A technique and apparatus to allow a determination of an MSAG-valid address by use of normalized house numbers included in address entries in an MSAG Address data store, to facilitate the simple match of an input civic/postal address against entries in a MSAG data store based on the use of a normalization of the house numbers. The house number normalization allows for an easy lexicographical determination as to whether or not the input civic/postal house number falls with the range of house numbers in the MSAG data store. The inventive process and apparatus pre-stores normalized house number fields in an MSAG address data store, and then normalizes house numbers in a civic/postal address associated with an emergency call. The normalized numbers in the input civic/postal address associated with the emergency call are then lexicographically matched with normalized entries in an MSAG address data store.