The new cars would have thicker walls, a thermal protection system and other improvements designed to minimize the possibility of fire or explosion in case of a derailment, said BNSF Railway spokesman Steven Forsberg.
He called the purchase of the new cars "an important milestone in the improvement of safety standards for the transportation of crude by rail." A request for proposals from major railcar manufacturers has already been sent out, he said.
The announcement comes after recent accidents that have led to questions about the safety of transporting oil by rail.
In December, an oil train derailed and exploded near Casselton, N.D. The accident occurred about a mile outside the town, and no one was hurt, but about 2,000 people were evacuated to avoid toxic smoke.
In July, a runaway oil train derailed and exploded in Lac-Megantic, Quebec, near the Maine border, killing 47 people.
The movement of oil into and through Washington state is changing dramatically as more crude oil from the Bakken shales of North Dakota arrives by train and creates potential risk for new areas of the state, such as along the Columbia River.
The state for years has received crude oil from Alaska and elsewhere by ship, barges or pipelines, but trains carrying crude oil started arriving at terminals in Tacoma and Anacortes only in the past year or so.
Facilities are being proposed at the ports of Grays Harbor and Vancouver to handle hundreds of thousands of barrels of crude oil by rail.
The new railcars proposed by BNSF would incorporate several safety improvements:
The tank car body shell and head ends must be built of 9/16 inch thick steel
Equipped with 11 gauge steel jackets and full-height, 1/2 inch thick head shields
A thermal protection system which incorporates ceramic thermal blanketing and an appropriately sized pressure relief device capable of surviving an ethanol-based pool fire
A bottom outlet valve handle that can be disengaged to prevent unintentional opening