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

New York (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.

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