While the probe of the crash is far from over, the Transportation Safety Board has determined the bus was travelling over the speed limit and that the driver may have been looking at a video monitor at the time of the tragedy.
"There's two issues here that we consider to be significant and that may have played a role in the accident," lead investigator Robert Johnston told a news conference.
The board issued two safety advisories as it laid out the progress that's been made so far in determining just what happened on Sept. 18, 2013, when the OCTranspo bus collided with the Via passenger train.
Investigators concluded that the bus was travelling at 67.6 kilometres an hour, just over the posted 60-kilometre limit, when its brakes were first applied just two seconds before impact.
The TSB is recommending that the City of Ottawa better monitor buses for speed infractions near railway crossings.
A second letter recommended the city review the use of video monitors in its buses.
Investigators pointed out the double-decker bus involved in the crash had several video displays in the area of the driver's cockpit.
One of those monitors was up high enough that, had the driver been looking at it, he may have been sufficiently distracted that he failed to notice the flashing rail guard lights ahead of the bus.
"In order for the driver to view the monitor, a driver has to physically remove his gaze from the forward motion of the bus and look at the monitor," Johnston explained.
"(Drivers) are instructed not to stare at the monitors, but even glances up to two seconds have been shown to be contributory in accidents."
The monitor above the driver is used to view people coming down the stairs from the upper deck of the bus and investigators said they have determined there was someone on the stairs while the bus was in motion that morning.
The board's interim report also said a coroner found that driver Dave Woodard had no medical issues at the time of his death and drug and alcohol tests were negative.
And it said there were no mechanical issues with the vehicle's air brake system.
Shortly after the deadly collision, the city reduced the speed limit near the crossing to 50 kilometres per hour. Investigators said municipal officials may want to implement additional measures to ensure drivers adhere to the new limit, or reduce speeds even further.
Following the release of the report, the city said it would immediately deploy radar enforcement units on the transitway in the area of the crash and elsewhere.
And it said it would pass on the board's letter about video monitors to a safety engineering firm it had already hired to review driver workload and the ergonomics of its bus fleet.
The city will also review its standard operating procedures and training for bus operators.
Board officials said their probe will continue with more assessments of the level crossing at the heart of last year's crash, along with a review of studies related to other railway crossings.
A final report on the crash investigation is likely still months away.
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