A railroad union has rejected a deal with U.S. railway BNSF, which operates in two provinces, that would have allowed one-person crews on as much as 60 per cent of its tracks.

The Sheet Metal, Air, Rail and Transportation Workers union voted against the contract this week, according to a notice sent to members late Wednesday.

The deal would have allowed BNSF to use one-person crews on tracks where a system capable of stopping the train remotely had been installed. But trains that carry hazardous materials, such as crude oil and chemicals, would have continued to have two-person crews.

BNSF operates tracks in 28 states in the western U.S., Manitoba and British Columbia. It runs spur lines to Winnipeg and Vancouver.

The runaway train operated by MM&A railway that destroyed the town of Lac-Mégantic, Que., last year was operated by a one-man crew. That crew member is one of three MM&A employees awaiting trial in the fiery crash, which killed 47 people.

The engineer, controller and train operations manager each face 47 counts of criminal negligence causing death.

BNSF railroad, based in Fort Worth, Texas, said it has Positive Train Control systems is installed on about 60 per cent of its 32,500 miles of track.

Train control system

BNSF and supporters of its proposal had argued that the implementation of Positive Train Control makes it unnecessary to have a second person in the cab of every locomotive. BNSF Vice-President of Labor Relations John Fleps said the railroad will honour the union's wishes.

"They have decided not to move forward at this time, and we respect the process," Fleps said.

Major U.S. railroads have been steadily reducing the size of train crews for decades to reduce costs and take advantage of technological advances that reduce the need for crew members. Union agreements requiring two-person crews have been in place for nearly 30 years.

Several different labour unions represent groups of railroad workers. The SMART group involved in these negotiations represents conductors and ground crew workers.

Regulators study rail crews

Regulators at the Federal Railroad Administration have said they are studying whether to require two-person crews on the major freight railroads for safety.

And labour groups have been working to persuade Congress to pass legislation requiring freight railroads to use two-person crews.

Congress ordered railroads to install train control safety systems by the end of 2015, but railroads have been seeking to delay that mandate to at least 2020 because of logistical and technical problems they've encountered.

The safety system is designed to address human error, which is responsible for about 40 per cent of train accidents. It uses GPS, wireless radio and computers to monitor train position and speed, and stop them from colliding, derailing because of excessive speed, entering track where maintenance is being done, or going the wrong way because of a switching mistake.

BNSF railroad is owned by Warren Buffett's Berkshire Hathaway Inc.