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10. Right on. When you personally transport classified material by car or on foot to another location within the same city or metropolitan area, the rule is that you must use the same procedures as apply to mailing classified information. Secret information must be double wrapped or packaged and appropriately marked. A single envelope will do only if it is within a locked briefcase, and then the briefcase counts as the outer wrapping. This helps protect the information under all foreseeable contingencies such as automobile accident, theft, or sudden illness.
The classified information must be kept under your personal control while you proceed directly to the other location (for example, not left in the trunk of your car while you stop for lunch or run another errand).
Special authorization is required prior to hand-carrying classified material on a commercial aircraft. If your travel involves an overnight stopover, you must make advance arrangements for secure overnight storage in a Government office or a cleared contractor facility. The classified material may not be kept overnight in your hotel room or in a hotel safe.
Related Topic: Mailing and Carrying Classified Materials.