BNSF Railway officials announced Feb. 20 that it intends to buy a fleet of 5,000 strengthened tank cars to haul oil and ethanol

The voluntary step by the Texas-based company would set a higher safety standard for a fleet that’s seen multiple major accidents.

A string of recent train accidents involving oil and ethanol follows a boom in domestic oil drilling and rising ethanol production. Much of the new petroleum production is being hauled by an old fleet of some 78,000 tank cars that have split apart in derailment accidents.

Railroad companies typically don’t own the tank cars they transport, making BNSF’s proposal somewhat unusual. But whether it will spur other shipping companies or railroads to follow suit is uncertain.

BNSF’s announcement marks a potential major step in addressing that problem, but the older tanker cars won’t go away soon — the company faces a two-year backlog on new tank car construction.

In announcing that it will ask manufacturers to submit bids for the new cars, BNSF indicated it was unwilling to wait for the U.S. Department of Transportation to finalize new regulations for improving tanker cars.

In addition to the older tanker cars that are prone to failure, about 14,000 tanker cars currently in use were built according to a more stringent standard established by the industry in 2011.

BNSF’s proposal would go further still. Among the added safety features being sought by the company are half-inch thick steel shields that would go on either end of the tank cars to help prevent them from cracking open during accidents. The new cars also would have pressure-relief valves capable of withstanding an ethanol-based fire, and a tank body made of thicker steel than existing cars.