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The list of acceptable ID's is here - http://www.tsa.gov/travelers/airtrav...documents.shtm

Employee ID's is not on the list, except for airline or airport workers. While the badge may look the same, they are probably considering who is issuing it in their decision to accept a DOD badge and not yours.

I can get a document that looks exactly like my drivers license, but they won't accept it if they know it's not a real license.