The National Transportation Safety Board on Thursday recommended new requirements for shipping crude oil by rail in an attempt to prevent disasters like a July derailment and explosion in Quebec that killed 47 people.

"NTSB is concerned that major loss of life, property damage and environmental consequences can occur when large volumes of crude oil or other flammable liquids are transported on a single train involved in an accident," the agency said, referring to the Lac Megantic, Quebec, incident.

One of the rules the board recommended to the Department of Transportation would require oil to be properly classified — the Pipelines and Hazardous Materials Safety Administration put out a warning earlier this month that crude from the Bakken shale formation in North Dakota and Montana might be more flammable than others.

Other rules would require railroads and shippers to plan routes that avoid populated areas and to develop safety and mitigation plans in case of an accident.

The proposals come after a handful of crude oil train derailments over the past month — one in Casselton, N.D., at the end of December that led to an explosion, another in New Brunswick, Canada, and one last week in Philadelphia.

Those events have shed a light on some of the complications arising from transporting an increasing amount of crude from the Bakken. Refiners have increasingly turned to railroads to deliver crude in absence of pipelines, the building of which has failed to keep pace with rapid oil production — the NTSB said crude-by-rail shipments have jumped 400 percent since 2005.

"The large-scale shipment of crude oil by rail simply didn't exist 10 years ago, and our safety regulations need to catch up with this new reality," NTSB Chairman Deborah Hersman said. "While this energy boom is good for business, the people and the environment along rail corridors must be protected from harm."

Members of Congress have pushed for action to strengthen safety regulations. Several have pushed the Department of Transportation to quickly finish new safety rules for the DOT-111 tankers that transport crude — the regulatory schedule of the Pipelines and Hazardous Materials Safety Administration published last week shows those rules will be finalized in 2015.