Annual U.S. incidents involving railroad tank cars carrying crude oil NUMBER OFINCIDENTS STATESAFFECTED GALLONSSPILLED NG STAFFSOURCES: clearview energy partners; phmsa

New U.S. rules will require trains carrying crude oil to have stronger tank cars, better brakes, and slower travel speeds. The chart above shows why: Rail incidents involving crude oil jumped nearly sixteenfold between 2010 and 2014.

The Department of Transportation coordinated its new regulation, announced Friday, with authorities in Canada. "The trains moving unprecedented amounts of crude by rail are not U.S. or Canadian tank cars – they are part of a North American fleet and a shared safety challenge," said Secretary Anthony Foxx.

The rise in crashes accompanies the burgeoning rail traffic from North Dakota's Bakken shale to points all over North America. Oil train accidents spread from eight states in 2010 to 21 states in 2014, according to the consulting firm ClearView Energy Partners' analysis of data from the U.S. Pipeline and Hazardous Materials Safety Administration.

They're still happening in 2015, including fiery derailments recently in Mount Carbon, West Virginia, and Galena, Illinois.

Both of those incidents involved the newer CPC 1232 cars initially proposed as a safer alternative to the DOT-111 cars involved in other accidents, such as the deadly derailment and crash in Lac Megantic, Quebec, that killed 47 people. Both car types fall under the new regulation.

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