"TSA has met with the Port Authority, who is responsible for the operation of the surveillance cameras, and will work with them to ensure consistent performance and confirm operational readiness," said Davis.
Sen. Robert Menendez, D-N.J., called the two-hour gap between the breach and the TSA's confirmation "unacceptable."
"This simple breakdown not only cost precious response time, it also prevented authorities from tracking the suspect and ensuring he was not a threat," Menendez said.
It took until 7:45 p.m. for the concourse to be emptied and a subsequent four-hour-long security sweep to begin. During that time, departing planes were delayed and arriving jets had nowhere to park, leaving passengers stranded on the runway waiting to deplane.
The redundant cameras have been in place since the pre-9/11 era when the airlines were responsible for their own security. Continental provided the tapes to the TSA as soon as the airline became aware the TSA wanted them. The inoperable cameras caused a two-hour gap between the security breach and when the TSA was able to confirm it.
Newark was one of the airports from which one of the four jets used in the Sept. 11 terror attacks took off more than eight years ago.
Once Sunday's breach was confirmed by TSA after 7 p.m., security screening stopped as an attempt was made to locate the man who had passed through the wrong door. Moments later, it was decided to remove all passengers from Terminal C -- the airport's busiest -- so that officers could search the concourse and every passenger could be rescreened.
It took several hours to sweep the empty Newark concourse Sunday night. Passengers were allowed to go back through security just before midnight.
"We had to take action that unfortunately inconvenienced a hell of a lot of people," Davis said.
Continental says more than 100 flights were impacted, and though the operation is "looking good" today, there are still some international flights that were behind schedule Monday afternoon.
"We're going to look at the timeline to see how we could have done better," Davis said.
These kinds of episodes happen on occasion, the TSA says. In the week that began Dec. 14, the agency says there were 37 incidents at airports across the country that involved a checkpoint closure, terminal evacuation or a sterile area breach.
Sunday's breach at Newark comes as the TSA implements new security procedures for passengers flying into the U.S. from countries tied to terrorism, in the wake of the attempted Christmas Day bombing of a plane headed to Detroit.
Passengers on flights arriving from Paris and Mumbai told ABC News they were frisked at their departure gates, and every piece of their carry-on luggage was searched.
"You had to take off your jacket, you had to take off your purse, they went through your purse and did the whole body thing," one passenger said.