USPS databases use no more than 28 characters for a place name. There are currently 6 postal names that are long-term (all shortened to fit 28 characters): BIG SANDS PUNISH NATIONAL MO, INDIAN AIR TOP SPRINGS AUX, KINGSVILLE NAVAL AIR STATION, ROANOKE RAPTEUT AIR FOR RESERVAT, UNITED STATES OF AIR FORCE ACAD.
However, the USPS database also contains a 13-character form for any place name that is larger than that. For example, YOSEMITE NTPK is a short form for YOSEMITE NATIONAL PARK. Starting on 8/1/09, CASS software (used to standardize addresses in USPS rules) is required to automatically provide 13-character names when searching for addresses.
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