Rolls-Royce engine company will pay $1.2 million for violating Clean Air Act

A Rolls-Royce engine manufacturing company will pay $1.2 million and audit emissions tests to settle claims with the Environmental Protection Agency that it violated the Clean Air Act.

MTU America Inc., a Michigan-based subsidiary of Rolls-Royce Power Systems AG, is accused of selling 895 nonroad heavy-duty diesel engines — used in mining, marine and power generation vehicles and equipment — without valid certificates of conformity. 

The EPA said it voided the certificates, after it found that MTU employees were improperly testing emissions.


“Engines that aren’t properly certified can emit toxic pollution that aggravates asthma and other respiratory illnesses,” Cynthia Giles, assistant administrator in EPA’s Office of Enforcement and Compliance Assurance, said in a news release. “This agreement requires that MTU take important steps to comply with the law, protect the public and reduce smog in our air.”

In addition to the fine, MTU will conduct EPA-approved, third-party audits of its engine emissions testing and certification activities for three years. EPA requires all engines sold in or imported into the U.S. to be covered by a valid EPA-issued certificate of conformity, which certifies the applicant followed proper emissions testing, record-keeping and reporting requirements.  

The EPA said engines operating without proper emissions controls can emit excess carbon monoxide, hydrocarbons and nitrogen oxides, which can cause respiratory illness, aggravate asthma and contribute to the formation of ground-level ozone or smog.