It's been more than two years since an Amtrak train killed two track workers in Chester. Now, that event — and the harsh criticism from federal authorities that followed — has led to new safety standards designed to protect workers doing track maintenance.

The new standards will protect Amtrak workers nationwide, and makes good on some recommendations the National Transportation Safety Board made after the Chester crash, including that labor and management cooperate to make rail work safer.

"These efforts are not limited to the BMWE [Brotherhood of Maintenance of Way Employees], and they are not limited to the Philadelphia region," said Beth Toll, an Amtrak spokesperson. "Amtrak has held a number of collaborative meetings with labor to develop the [safety management system], and we continue to work with our labor organizations to reduce risk throughout the operation."

However, the agreement doesn't include a key NTSB recommendation following the Chester crash: To give workers and maintenance equipment GPS devices that would automatically alert a train and dispatchers to their presence.

"My attitude is, Amtrak has to do it," said Steven Ditmeyer, a rail consultant and a former Federal Railroad Administration executive. "It really is not optional."

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The announcement of the changes came in an Aug. 22 letter co-authored by four rail worker unions.

"What we can do is resolve to give their deaths meaning by ensuring that every one of us goes home to our families at the end of our tour of duty alive and well," the union letter stated.

Five maintenance of way workers have been killed by moving trains in the last four years, the letter states, including the two men killed in the Chester derailment. The most recent, Luke Gsell, 20, died on April 24, in Bowie, Md., less than six months after the NTSB faulted Amtrak for having a poor safety culture. A watchman, Gsell was standing along the edge of railroad ties when he died, signaling an approaching commuter train to alert it to workers' presence. He was struck from behind and killed by an Amtrak train he didn't see coming, according to a document from the Brotherhood of Maintenance of Way Employees.

The union letter stated the work site should have had seven watchmen assigned, but there were only three that day.

Union representatives did not return calls for comment. The death is under investigation by the NTSB.

The Maryland crash and the one in Chester both involved trains passing through sites where people were working on tracks.

On April 3, 2016, Train 89 en route to Savannah, Ga., hit a backhoe alongside the track in Chester. During a shift change just before the crash, a night supervisor and a day supervisor failed to communicate properly and didn't maintain protections that would have prevented a train from being routed onto a track where workers were present.

The NTSB recommended after the Chester crash that there be a system in place for workers to report safety problems and that there be speed restrictions imposed around work zones. The new rules address both points.

Workers have long sought a channel to report safety problems without fear of reprisal. Transportation agencies often have a no-fault system of reporting "close calls," incidents that didn't result in an accident but could have. Amtrak hasn't had one since 2014, and meanwhile created a highly punitive safety system. The NTSB found in its 2017 review of the Chester crash that the rail agency had developed a culture that failed to make safety a priority, as fear of discipline trumped concern for safety. The new rules create a panel of labor and management staff who will review complaints from workers and try to fix the safety problem.

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Amtrak has been developing new safety standards since the Chester crash and said a close-call reporting system was a key component of that system.

The recent rules changes require a 60 mph restriction for any trains passing alongside tracks where certain pieces of heavy maintenance equipment are being used. The union letter noted the train in the Maryland crash was traveling at 105 mph, too fast for people to get out of the way by the time it was spotted. The train in the Chester crash was traveling 100 mph.

The new standards also require watchmen to always stand away from the tracks and promised platforms or stands that could be attached to catenary poles for workers, and would provide information on the number of watchmen needed to safely observe certain stretches of track.

Ditmeyer called the changes "very desirable."

He emphasized, though, that the automatic speed control system Positive Train Control (PTC) allows many of the safety functions on the railroad to happen without any input from people. PTC is active throughout the Northeast Corridor rails owned by Amtrak, the rail carrier has said, which includes the locations where the Chester and Maryland incidents happened. Toll would not confirm Friday, though, whether PTC was active when Gsell was killed.

Ditmeyer noted the 60 mph speed restriction is a good idea, but one that still requires proper communication between workers on the track and a dispatcher. If workers are equipped with devices that would automatically alert a PTC system to their presence, as the NTSB recommended, a communication failure might not result in catastrophe.

"In four years, too many people died," he said. "That's too many. GPS and data radios are not that expensive."

Amtrak is in the process of testing such systems, Toll said.