Tank cars used by oil and gas companies to transport crude oil and ethanol across the United States will have to comply with stringent new standards under new draft rules presented by the U.S. Department of Transportation last week.

The proposals aim to improve the safety of crude shipments by rail and make tank cars more resilient in case of accident. As part of the proposals, railway operators and oil and gas companies will have to stop using cars manufactured prior to October 2011 within the next two years. Such cars may still be used only if they have been been fitted with special equipment that allows them to comply with new standards, including improved braking systems and thicker shells, the Department of Transportation said.

According to the department, the new standards would radically change the way in which high-hazard flammable substances are shipped across the country, at a time when crude transport by rail is increasing in volume. In 2013, as many as 415,000 rail-carloads of crude were shipped through the United States, compared to just 9,500 rail-carloads in 2008.

The proposals are based on an earlier report by the Pipeline and Hazardous Materials Safety Administration. Transportation Secretary Anthony Foxx commented that the proposals marked significant progress in developing new rules that would improve the safety of shipments of all flammable liquids, including Bakken crude and ethanol.