Federal investigators are scrutinizing a Long Island Rail Road engineer’s sleep pattern, whether he texted and what he may have consumed during the 72 hours before the locomotive he was operating derailed Wednesday in Brooklyn, a spokesman for the National Transportation Safety Board said Saturday.

Board spokesman Peter Knudson said experts in analyzing tracks, signals, mechanics and human performance and other specialists were examining as many factors as possible that may have led to the crash, which injured more than 100 people during the morning rush.

A federal source told Newsday this week that concerns about the 50-year-old engineer’s health suggest that sleep apnea may have been a factor and that the train made an “erratic” movement just before the crash. He has been on the job for about 17 years.

The crash was the first rail accident investigated by the NTSB in 2017.

In addition to reviewing the engineer’s “sleep-rest cycle” and the results of a standard screening for drugs and alcohol as part of the “72-hour background,” investigators will analyze his training records, medical history and other personal factors, said Knudson, whose agency investigates aviation, marine, railroad and other accidents.

“Was there a major stress event? Was there something that went on that could have played a role in the operator’s ability to safely operate the train?” Knudson said.

The preliminary accident report about the crash is expected to be released to the public within 30 days, with the final report expected in a year’s time or longer, he said.

In consultation with the manufacturer, the engineer’s labor union and the LIRR, the agency’s experts will review the train’s maintenance records, recent repairs, and details such as the signal system — asking what color was the traffic signal, should it have been the color that it was lighted, was it adequately illuminated and was there an anomaly with the track geometry.

Train engineers suffered from sleep apnea in two recent commuter railroad crashes in the region — the crash of an NJ Transit train in Hoboken in September and the derailment of a Metro-North train in 2013 in the Bronx. Both were deadly.

The NTSB will subpoena the engineer’s cellphone records to check whether he was texting or using the phone. Acquiring the records is a standard part of all probes, Knudson said.