The NTSB found a northbound train traveling at 22 mph struck an on-track vehicle Smith was standing near. The vehicle then struck Smith, who died from his injuries.

MARTA had implemented various procedures to protect its employees and contractors. And it had deployed four flaggers to control the movement of trains and protect workers.

But the NTSB found the primary flagger violated numerous safety protocols. The flagger failed to obtain proper authorization before directing Smith to move outside a restricted area. Among other things, the flagger also failed to appropriately block trains from entering the area and did not remain alert for trains.

The NTSB also faulted the operator of the train, who did not scan the track ahead before pulling out of the station and didn’t monitor track conditions as the train proceeded.

MARTA did not immediately respond to a request for comment.

Smith’s family has filed a wrongful death lawsuit in Fulton County Superior Court. Their attorney, Rudjard Hayes, said MARTA should have properly trained and supervised its employees to ensure they followed safety procedures.

“It’s a tragedy,” Hayes said. “Rob was a great guy with two kids and a wife who don’t deserve this.”

In its statement, MARTA said it suspended all work along its tracks immediately after the accident to conduct safety briefings and “systemwide refresher sessions on standard operating procedures” for the appropriate employees and contractors.

The agency also said it requested a peer review by the American Public Transportation Association. It did not say whether that review has been completed or indicate the outcome if it has.

It’s not the first time a MARTA train has struck and killed a worker. In 2000, three workers died in two separate incidents.

In the first, one MARTA employee was killed and another injured when they were struck as they inspected track near the Avondale station.

In the other, a father and son — both MARTA contractors — were struck and killed after repairing ceiling tiles at the Lenox station. MARTA later paid their family a $10.5 million settlement.