Then-presidential candidate Donald Trump shakes hands at a campaign appearance at Fitzgerald Peterbilt in Glade Spring, Va., in August 2016. The company is affiliated with Fitzgerald Glider Kits, which has pushed the Trump administration to repeal tighter emission standards for some freight trucks. (Evan Vucci/AP)

The president of Tennessee Tech University has disavowed a study used to help justify the repeal of tighter federal emissions standards for a type of freight trucks, saying that experts now question “the methodology and accuracy” of the industry-funded test.

Fitzgerald Glider Kits — which makes new truck bodies, called gliders, that house refurbished engines — had included a letter signed by Tennessee Tech’s president Philip B. Oldham and the head of the school’s Center for Intelligent Mobility, as part of its petition calling on the Environmental Protection Agency to withdraw a 2016 rule requiring that gliders comply with the same pollution limits as new heavy-duty trucks. The Washington Post first reported in November that the study was sponsored by Fitzgerald, the nation’s biggest glider manufacturer, and conducted at a Fitzgerald facility. The company’s connection to the university also extended to that research center, which soon will be housed in a new facility built by Fitzgerald.

In a letter Monday to EPA Administrator Scott Pruitt and Rep. Diane Black (R-Tenn.), who initially received the study results, Oldham wrote that “knowledgeable experts within the University have questioned the methodology and accuracy of the report” on the trucks’ performance. The school “is investigating an allegation of research misconduct related to the study,” he added.

“We request that you withhold any use or reference to said study pending the conclusion of our internal investigations,” he wrote.

The request was first reported Wednesday evening by the New York Times.

Previous EPA modeling, which assumed that most gliders use pre-2002 engines, found that they emit anywhere from 20 to 40 times as much nitrogen oxides and soot as trucks with new engines. But the petition filed by Fitzgerald, Harrison Truck Centers and Indiana Phoenix cited the Tennessee Tech testing that concluded gliders “performed equally as well and in some instances outperformed” vehicles with newer engines.

In the Federal Register notice that EPA filed in November proposing the rule’s withdrawal, the agency cited the study in a section explaining why Fitzgerald and other petitioners considered the regulation to be flawed.

An EPA official noted on Wednesday that the agency did not use the university’s analysis as the basis for the rule’s withdrawal, which was focused on a statutory and legal analysis. “Rather, EPA cited the petitioners’ own representations of the study, and that’s as far as it went,” said the official, who spoke on the condition of anonymity because the rulemaking process is still underway.

Fitzgerald officials could not be reached for comment on Wednesday.

The Obama-era rule was slated to take effect in January. Until the EPA adopted the 2016 glider regulation, trucking companies could put an outdated engine in a new truck body and avoid regulations that would apply to an entirely new truck. Heavy-duty trucks have faced tighter emissions standards since 2004, though they have become more stringent over time, thereby widening the gap between new vehicles and truck bodies with older engines.

The EPA had previously projected that the gliders sold in a single year would generate pollution over their lifetime that could result in between 350 and 1,600 premature deaths and that the rule would generate between $1.5 billion and $11 billion in related public health benefits. The agency did not publish a cost-benefit analysis when it issued its proposal to overturn the 2016 standard, and it did not wait for its own automotive experts to complete emissions tests on a glider the agency had independently purchased.

Those agency tests ultimately found that glider trucks emit between 40 and 50 times more soot and smog-forming pollutants as a comparable new truck.

The 50-day public comment period on the withdrawal proposal closed last month. Paul Billings, senior vice president for advocacy at the American Lung Association, had unsuccessfully requested that the period be extended.

Tennessee Tech’s disavowal of the study, Billings said Wednesday, “lays bare that there was no analysis” to underpin revoking the Obama-era standard.

Andrew Linhardt, deputy legislative director for the Sierra Club, said that if the market for gliders — which stands at about 10,000 vehicles per year — were to keep increasing, “They would continue to have huge pollution implications which affect all of us.” He said he hopes the university’s action gives the EPA “second thoughts” about moving forward with its plan to unwind the Obama regulations.

In recent weeks, many Tennessee Tech students, faculty members and officials have questioned how the initial study was conducted. The interim dean of its College of Engineering, Darrell Hoy, sent a letter to other faculty members saying that “no qualified, credentialed engineering faculty member” oversaw the testing, verified the data or reviewed the report that was sent to Fitzgerald.

In November, Tennessee Tech spokesman Dewayne Wright said that one of the school’s engineering professors went with graduate students “to a Fitzgerald facility to conduct independent research” on the EPA rule and the company paid just over $70,000 to finance it. “The Tennessee Tech faculty member and students were in control of the testing, which was done using university emissions testing equipment,” Wright explained. “Once collected by the university members, the data was brought back to the university from the Fitzgerald facility for analysis.”

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