Travel has changed significantly after 9/11 event. A major area of change has been with airport security and travel security in general New protocols have been adapted, and many airports require thorough security checks in both domestic and international flights.
TSA, also known as Transportation Security Administration was founded in the wake of 9/11 to strengthen the security of the United States transportation systems. They are involved in both land and air travel securities, and are the faces comely seen at the security lines at the baggage screening at airports in the United States.
TSA electronically screen million of bags for explosives and other dangerous items each day at more than 7000 baggage screening locations and at over 450 airports in America. In this baggage check process, TSA requires access to air passenger's luggage without passenger being present. To let passengers still use locks to prevent thefts, TSA has approved certain locks, which can be identified by their logo and TSA personnel can open and relock with special tools and information supplied by the lock manufacturers. Those are called 'TSA locks' or 'TSA approved locks'. Simialr protocols have been adapted by the United Kingdom and are being considered in a range of other countries.
There are different types of TSA locks in the market. Some comes with indicator, (such as the Boomerangit Lock offered by Safe Skies http://www.safeskies.com.au/Products/BoomerangIt-TSA-Locks.aspx ) which whether a bag has been opened by security. When TSA security officer unlocks your TSA lock with their master key, the indicator turns to red. After you relock the padlock with your own key, the indicator goes back to green.
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