All staff and most diplomats were evacuated from United Nations headquarters in New York Friday in a practice drill.

On September 11, the day of the terrorist attacks on the United States, the U.N. building was evacuated, but there were numerous problems. The public address and alarm systems were not fully working, and there was widespread confusion among staff members as to how they were to exit the building and where they were to go.

Since then, U.N. security officials have been working to ensure all communications systems are working properly and that an orderly evacuation plan is understood by everyone. Everyone at the headquarters building, except U.N. Security Council members, who were discussing an anti-terror resolution, was required to evacuate.

There are periodic fire safety drills at the United Nations, but this was the first total building evacuation drill since 1979.

U.N. spokesman Fred Eckhard says it was certainly time for another one. "Every once in a while, we should really practice evacuation of the building; and in light of the September 11 events, we think practice is particularly appropriate now," he said.

U.N. headquarters is under tight security in normal times, with everyone, except diplomats and full-time staff, required to pass through metal detectors and submit packages to x-ray screenings.

Since the terrorist attacks, security has been tightened, with all public tours of the building canceled, and police and U.S. Coast Guard boats patrolling the East River behind the 38-story building.