WASHINGTON — Federal officials have begun drafting safety standards for the nation’s subway and light-rail systems, three years after a deadly crash on a Washington transit line exposed vast gaps in oversight of trains that transport millions of people a day.
The Transportation Department has long regulated safety for airlines and Amtrak, but it had no authority to impose safety standards for subway and light-rail systems. The result, federal officials said, was a patchwork of rules and regulations covering systems from San Francisco to Washington.
Now, the federal government is carving out a bigger role in the safety of such systems. In the summer, Congress approved a measure expanding the authority of the Federal Transit Administration and strengthening the role of state monitoring agencies.
“These first-ever federal safety standards will ensure we can bring the full force of our national transit expertise to help promote a culture of safety on our nation’s rail-transit systems,” said Senator Barbara A. Mikulski, Democrat of Maryland, who led the push for federal oversight along with Representative Donna F. Edwards, also a Maryland Democrat.
Federal officials met last month in the District of Columbia to discuss the new rules, which will take several months to write.
At a minimum, transit agencies will be required to have strategies for identifying safety risks, to employ a trained safety officer who reports directly to the head of the transit agency, and to have training programs for employees responsible for safety. State agencies will be required to meet new standards and to be certified by federal officials.
The push for federal oversight was prompted in part by the growing number of derailments, collisions, and worker fatalities on subways — notably the 2009 crash on the Red Line of the Washington Area Metropolitan Transit Authority, which killed nine people and injured more than 80 others.
Federal officials expressed frustration that a 1965 law prohibiting federal regulation of subways was preventing them from taking necessary steps to ensure public safety.
‘‘The law actually prohibited DOT and FTA from being involved in safety oversight,’’ Transportation Secretary Ray LaHood said. ‘‘The fact is there is no standard, no transit safety program that people nationally can look to as a model.’’
LaHood said the goal of the new rules is not to drown local agencies in federal regulations. Rather, federal officials will focus on a common-sense approach that puts safety first, he said. Although the US government will set minimum standards, it will not regularly monitor local operations unless state oversight is inadequate.
A spokesman for the American Public Transportation Association, an industry group that has published its own set of safety standards, said it is too early to know what adhering to the standards might cost transit agencies.
‘‘We think it’s a very safe industry,’’ the transportation association’s Mantill Williams said. ‘‘But at the same time, we’re open to making it safe and improving things.’’
After the 2009 crash, a federal investigation identified significant flaws in the transit authority’s safety practices, including safety problems that went uncorrected for years, and lent urgency to the lawmakers’ campaign for federal oversight.