Three of the crew members involved in the Goodwell crash were obese, McKay said, and at least one had hypertension. It wasn't known whether any were diabetic or had sleep disorders, she said.
In regard to Hall, the engineer on the train that didn't obey the signals, his Texas driver's license was limited to daytime driving.
Hall, who was 56 and lived in Dalhart, Texas, had visual acuity of 20/70 in his right eye and 20/200 in the left on his last visit to the ophthalmologist three weeks before the collision. Visual acuity of 20/40 is required for certification.
The NTSB said Union Pacific did not comply with its own policies when it medically recertified Hall. The company requires a color test of 10 signals, but only six were available when he took the test, the NTSB staff reported.
Union Pacific responds
Union Pacific responded Tuesday that “our records indicate the engineer passed all of the federally mandated vision tests, and suggestions that his vision may have contributed to the accident are pure speculation.”
“The accident that occurred in Goodwell, Oklahoma, was a tragedy that was deeply felt by the Union Pacific family,” the company said. “We were fully cooperative during the NTSB's investigation and plan to continue to invest in training, equipment and network infrastructure to ensure the safety of our employees and the communities in which we operate.”
The company said it would invest $450 million this year — and $2 billion overall — to implement Positive Train Control. More than 200 signals are installed with the technology, and about 1,200 locomotives are partially equipped, the company said.