WASHINGTON, D.C. — President Obama on Tuesday signed the Diesel Emissions Reduction Act (DERA) into law after it was approved last month by Congress.

The move reauthorizes for another five years the bipartisan program, which provides funds to reduce emissions from school buses and other diesel vehicles.

The reauthorization bill was introduced in November by Senators George Voinovich (R-Ohio) and Tom Carper (D-Del.) and cosponsored by several of their colleagues.

"By cleaning up old diesel engines — like those on the school buses that take our children to school every day — DERA saves lives and creates a demand for clean diesel technology, which in turn creates American jobs," Carper said. "DERA leverages federal dollars so efficiently that for every $1 invested, we get over $13 in health and economic benefits in return."

On Tuesday, Carper held a press conference and toured recently retrofitted school buses at Delaware's Cape Henlopen School District, a recipient of DERA grants.

Allen Schaeffer, executive director of the Diesel Technology Forum, called DERA "one of the most important clean air initiatives passed by Congress in recent years."

“The combination of new clean diesel technology and ultra-low sulfur diesel fuel has helped to reduce diesel emissions to near zero levels for new buses, trucks and off-road equipment," Schaeffer said. "Now the older engines that continue to power our economy will also benefit from the upgraded engines and filters provided by DERA."

The National School Transportation Association (NSTA), one of the members of the broad DERA coalition, said that it fought for changes that were included in the final version to allow for direct applications from private entities under contract to federal, state or local governments; streamlining the application process, especially for small businesses; and giving higher priority for projects that benefit school areas.

The annual appropriation level reportedly was reduced from $200 million to $100 million to ensure the bill's passage, but NSTA noted that that level is still higher than the past three annual appropriations.