MEMPHIS, Tenn. — ExpressJet Airlines first officer Michael Roberts drew a line in the sand at Memphis International Airport security Checkpoint C.

He left the airport without boarding a flight to his duty base in Houston, refusing a full-body scan and its alternative, a manual pat down, by Transportation Security Administration officers.

Now, Roberts, 35, was waiting to find out whether his protest would cost him his job.

“I’m not trying to throw down the gauntlet with the federal government per se,” he said. “I just want to be able to go to work and not be harassed or molested without cause.”

“I just kind of had to ask myself ‘Where do I stand?’ I’m just not comfortable being physically manhandled by a federal security agent every time I go to work.”

TSA spokesman Jon Allen, citing privacy considerations, wouldn’t confirm that Roberts was the person who was turned away by airport police after refusing to comply with TSA security procedures.

However, Allen said the incident was the first of its kind at the Memphis airport since TSA began rolling out advanced imaging technology, or full- body X-ray scanners, at the airport in September.

Officials at ExpressJet, a regional airline that operates Continental Express flights out of Memphis, did not respond to multiple telephone calls and e-mails seeking comment.

Roberts said he had been going through security at Memphis without incident for 4 1/2 years. He said last Friday was his first time at the checkpoint since new scanning equipment was installed.

TSA officials have said passengers are selected to undergo the scan at officers’ discretion. If a passenger opts out of the scan, the alternative is to be frisked. Passengers still go through metal detectors if they aren’t selected for the enhanced screening options, Allen said.

Roberts was wearing his pilot’s uniform and identification at the time.

“For a guy like this, who is probably going through once or twice a week, who has been doing it four or five years, you’d think they would just know him and say, ‘Hi, how are you?’ and would just pass him through with normal screening,” said Scott Erickson, a Pinnacle Airlines Inc. captain who heads Pinnacle’s unit of the Air Line Pilots Association.

Erickson said his members are divided over the new screening procedures, particularly questioning whether health risks are as insignificant as TSA claims. “It’s certainly not universal. Some people have the privacy concern, others don’t.”

The scanner produces an image of the surface of a person’s body and shows metal or nonmetal items hidden beneath clothing. The image is checked by an officer who is isolated in a viewing room and has no way to personally identify the passenger.

Erickson said Memphis-based flight crew members don’t have to follow the same procedures as the public.

Had Roberts been on a flight crew operating out of Memphis, he likely would have had a security clearance badge allowing him to bypass checkpoint procedures, Erickson said.

TSA experimented with an ALPA-proposed system, called CrewPASS, that would have standardized passage of airline crews through security, but the system wasn’t implemented, Erickson said.

Roberts said he’s not minimizing the importance of tight security to protect air travelers, but he said he doesn’t believe TSA has the answer.

“I have those (security) concerns as well, but I don’t believe this approach is a necessary or effective way to mitigate the threat.”

He called TSA a “make-work” jobs program combined with a feel-good effort “to give us a false sense of security to let us believe the folks in Washington are keeping us safe.”