TORONTO (AP) — Canada is proposing tough new standards for rail tank cars used to transport crude oil in response to a string of fiery crashes. 
The proposal, posted online Wednesday by Transport Canada, would require the cars to have outer "jackets," a layer of thermal protection, and thicker steel walls.
The requirements are tougher than the oil industry wanted. But the proposal doesn't include electronically-controlled brakes that automatically stop train cars at the same time instead of sequentially, which are opposed by freight railroads. Regulators said they will take that issue up separately.
Final regulations are expected by mid-May. U.S. officials have been working closely with Canada on the regulations and the White House is reviewing draft proposal.
There have been four oil train derailments in the U.S. and Canada since mid-February.
