WASHINGTON (Reuters) - A federal appeals court on Wednesday temporarily blocked a decision by the U.S. Environmental Protection Agency that would have lifted strict limits on the number of remanufactured heavy duty vehicles known as “glider trucks” that could be sold.

An empty podium awaits the arrival of U.S. Environmental Protection Agency (EPA) Acting Administrator Andrew Wheeler to address staff at EPA headquarters in Washington, U.S., July 11, 2018. REUTERS/Ting Shen

The vehicles have a used engine in a new frame and rules introduced under former President Barack Obama, a Democrat, said nearly all new trucks on the road must use more efficient, less polluting engines.

The glider trucks emit up to 450 times more diesel particulate matter and up to 40 times more smog-forming nitrogen oxides than new trucks on the market, the EPA has said

EPA issued a memo on July 6 that said the agency would not enforce a limit of up to 300 gliders per manufacturer. The EPA in November formally proposed undoing the glider rule but has not finalized it. The EPA, which said Wednesday it was reviewing the decision, had said in its memo that enforcing the rules would result “in the loss of jobs” and threaten the viability of companies making the glider trucks.

Volvo Group North America, Cummins Inc and Navistar International Corp said last year they opposed efforts to reverse the limits on glider trucks.

Glider kits “should not be used for circumventing purchase of currently certified powertrains.” The move could inflict “uncertainty and damage to our industry,” the companies said.

Environmental Defense Fund President Fred Krupp said the “decision today is an important step toward protecting the health of all Americans from super-polluting diesel freight trucks.”

The U.S. Court of Appeals for the District of Columbia said the EPA must respond to the lawsuit from environmental groups by July 25. The court order said the “stay is to give the court sufficient opportunity to consider the emergency motion” and not a ruling “on the merits” of blocking the memo.

The EPA has previously said that if gliders were allowed through 2025, they would make up 5 percent of the freight trucks on the road but would account for one third of all nitrogen oxides and particulate matter emissions from the heavy truck fleet.

Glider companies told the EPA that glider trucks are 25 percent cheaper than new vehicles.

In August 2016, the Obama administration issued final rules to cut greenhouse gas emissions from medium and heavy duty trucks through 2027, a sector that accounts for 20 percent of carbon pollution from vehicles.

The commercial vehicle rules are expected to cut 1.1 billion metric tons of greenhouse gas emissions, the Obama administration estimated.