(CNN) -- A nationwide review of the air traffic control system has been ordered after an air traffic controller admitted falling asleep while on duty at a Washington airport, a federal agency said Friday.
In addition, "effective immediately, we are instituting an interim plan to ensure we do not repeat another situation like the one at Reagan National Airport," a statement from Federal Aviation Administrator Randy Babbitt said.
Early Wednesday, an air traffic controller at Ronald Reagan Washington National Airport failed to respond to two planes heading into the airport.
The National Transportation Safety Board said Thursday that the controller later "indicated that he had fallen asleep for a period of time while on duty." The controller "had been working his fourth consecutive overnight shift (10:00 p.m. to 6:00 a.m.)," the board said.
The controller's admission that he was asleep as the planes approached the airport underscores concerns about the effect of fatigue on controllers at work.
"I have ordered a nationwide review of the air traffic control system to confirm the appropriate backup procedures and equipment are in place and in use," Babbitt said in the statement. "I am determined to make sure we do not repeat Wednesday's unacceptable event."
The temporary plan announced Friday requires that a regional controller, before instructing an aircraft to radio the control tower at the destination airport, will contact that control tower to assure there is a controller prepared to handle the incoming flight, the statement said.
Babbitt said he has also "reminded all air traffic controllers that proper procedures dictate that they must offer pilots the option to divert to another airport if they do not make contact with the control tower."
That apparently didn't happen during the incident Wednesday morning. A National Transportation Safety Board investigator who reviewed tapes of radio communications says the regional controllers did not advise the pilots they had the option of landing at other airports, board spokesman Peter Knudson said. But, he noted, pilots generally are aware they have that option.
The FAA changes will affect approximately 30 airports across the nation that customarily have only one controller working during the midnight shift.
The air traffic controller in the Washington incident has been suspended from all operational duties.
Department of Transportation Secretary Ray LaHood and Babbitt also have said that effective immediately, at least two controllers will have to be on hand in the Reagan National Airport tower at all times..