Shannon Airport in Ireland’s West became the first airport outside Canada, Bermuda and the Caribbean to provide full pre-clearance facilities for passengers flying to the U.S.

The airport launched their full U.S. Customs and Border Patrol (CBP) pre-clearance facilities on Wednesday for all transatlantic flights to the U.S.

Before then, travelers from Ireland to the U.S. went through a more limited pre-clearance in Shannon or Dublin, and were still required to go through customs and agriculture inspections upon their arrival in the States.

Then in November 2008, Irish Transport Minister Noel Dempsey and senior U.S. officials signed an agreement for full pre-clearance at Shannon.

For the past nine months, the Irish airport has been developing a new passenger screening area, new inspection area, post-clearance passenger holding lounges and a secure baggage holding area to accommodate the change.

U.S. Ambassador to Ireland Dan Rooney visited Shannon Airport on Wednesday to launch the new service and welcome the first passengers to be fully cleared before traveling to the U.S.

Shannon Airport’s director, Martin Moroney, said that the new security facility will provide business development opportunities for the area.

“This is an historic day for our airport and, indeed, a milestone moment in Irish-US relations,” he said. “Shannon is the first airport in Ireland to have these facilities in place, and [it] represents a major upgrade of the pre-inspection which commenced in 1986. It is a very proud moment for us and we look forward to maximizing this opportunity in the years ahead.”

Representative of that fact is British Airways’ decision to have a stop in Shannon to avail of the new pre-clearance service for its all-business flights from London to JFK Airport in New York.

Full U.S. pre-clearance facilities are scheduled to open up at Dublin Airport by November 2010.