Wearable RFID device for use in an event-based interrogation zone

A temporary installation of a system of RFID-based terminals and user-worn RFID devices within an event interrogation zone, the installation comprising:

• a plurality of terminals temporarily installed in the zone, each terminal having an active RFID reader, and being in communication with a server;
• a plurality of RFID devices issued to users wishing to enter the zone, each RFID device comprising:
• an element worn by a user;
• and
• an attached or embedded RFID tag having a memory having a first sector with read-only memory storing a UniqueID of the tag, and a second sector with a read-write memory storing stored data including a stored funds balance;
• the initially inactive terminals being programmed for:
• activating upon presentation by a user of the RFID tag of one of the RFID devices to the RFID reader using a first tap, and retrieving the UniqueID of the RFID tag;
• validating the RFID tag by comparing the retrieved UniqueID to a database of valid UniqueIDs stored on a server in communication with the terminal;
• receiving input of transaction particulars through the terminal;
• processing the transaction after the validated RFID tag is presented to the RFID reader of the terminal in a second tap, the processing including altering the stored funds balance on the read-write memory of the RFID tag;
• and
• inactivating the terminal after the tag is removed.