Since January 2011, U.S. Customs and Border Protection has offered U.S.-bound travelers preclearance services from Dublin Airport in the Republic of Ireland-allowing DHS to screen travelers for takeoff through the same process a traveler would undergo upon arrival at a U.S. port of entry to better target and prevent threats while streamlining legitimate travel.
Preclearance in Dublin was phased-in over time and Aer Lingus began taking advantage of the service after first ensuring their operations would synchronize with CBP's. The phase-in period is now completed, all flights from Dublin Airport are using preclearance, and the technical amendment authorizing Dublin preclearance operations published in the Federal Register on April 25.
In order to meet U.S. screening standards, the Transportation Security Administration (TSA) has trained members of the Dublin Airport security staff on TSA-approved screening procedures. Crew and travelers' carry on baggage are also precleared before departure from Dublin, allowing airlines to fly directly to U.S. airports. Without preclearance, U.S. bound flights must arrive at U.S. international airports where travelers go through the CBP entry and inspection process.
On Dec. 30, 2010 Secretary of Homeland Security Janet Napolitano announced the expansion of preclearance services to commercial aircraft departing and passing through Dublin Airport for the United States. Dublin Airport's preclearance center began processing approximately 1,000 passengers per day on U.S. carrier flights in January 2011 and added Aer Lingus flights in February. Today, approximately 2,500 passengers per day on all U.S. bound flights are precleared in Dublin prior to departure to the United States.
CBP currently provides preclearance services at 15 foreign locations in five countries, including Ireland's Shannon Airport, where CBP began preclearance services in August 2009.