A partial BART track closure is scheduled Wednesday as the National Transportation Board continues its investigation of Saturday's train accident that killed two workers.
Officials said a BART train traveling 60 to 70 miles per hour struck and killed two BART employees, 66-year-old Laurence Daniels of Oakland and 58-year-old Christopher Shepard of Hayward.
NTSB Investigator Jim Southworth said the two had radioed the dispatcher to say they were on the tracks.
"The responsibility of their safety is on themselves," Southworth said.
Under BART's rules, one of the two workers was to be a lookout positioned outside the right of way to warn the other of an approaching train.
The conductor also sounded the train's horn, Southworth said.
There was no radio warning from the train operator or the dispatcher that they were approaching the area -- it's not required, officials said.
Southworth said tests on the lights and brakes show them fully operational, though the brakes show flat spots, possibly from the conductor slamming them before the accident. There are cameras on board the train, but none point forward down the tracks.
The NTSB will close BART tracks Wednesday from 12 to 3:30 p.m. between Lafayette and Pleasant Hill in their search for more answers.
"Typically what the NTSB will do is try and do a reenactment and site distance testing at the same time the accident occurred," Southworth said.
A bus bridge will shuttle BART passengers between the affected stations.
None of the six people on board at the time of the accident will participate in the reenactment. That includes the four people in the passenger compartment, and the two charged with operating the train, an experienced trainer, and a BART manager, training for his certification, in the drivers seat.
The Associated Press contributed to this report.