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Story highlights

The September crash killed one and injured more than 100

The diagnosis doesn't necessarily mean the disorder caused the crash, according to an NTSB source

(CNN) —  

The New Jersey Transit engineer involved in the fatal train crash in September was diagnosed post-accident with sleep apnea, according to his lawyer and an official with the National Transportation Safety Review Board.

The engineer, Thomas Gallagher, was examined a week after the accident, but testing was delayed based on medication he received as a result of the crash, according to his attorney, Jack Arseneault.

The diagnosis, which was provided to the NTSB on October 31, does not mean that the engineer fell asleep at the controls, and it doesn’t mean the disorder had anything to do with the cause of the crash, the NTSB source said.

“It’s interesting and we will look at it, but we look at everything,” the NTSB official said.

The crash, which happened at a busy Hoboken terminal during the morning rush, killed one woman who was standing on the platform and injured more than 100 others.

The cause of the crash has not yet been determined.

Gallagher, a 29-year veteran of the rail line, received an annual physical through New Jersey Transit in July and was found fit for duty, his attorney said. It’s unclear to what extent sleep disorders were tested in that examination.

New Jersey Transit confirmed in a statement that it has a sleep apnea screening program but did not discuss the employee’s medical history.

According to the National Institute of Health, sleep apnea is a chronic condition that occurs when breathing pauses or becomes shallow during sleep, resulting in daytime tiredness.

The NTSB recommended that the Metropolitan Transit Authority, a separate, popular tri-state rail line, institute sleep apnea testing after one of its engineers fell asleep while controlling a train in 2013, killing four. It was later found that the engineer had an undiagnosed case of the disorder.

CNN’s Kristina Sgueglia contributed to this report.