US automakers told EPA toughening stance on emissions tests

U.S. environmental regulators are sending a letter to all automobile manufacturers saying the Environmental Protection Agency is stepping up emissions-testing activities in response to Volkswagen's alleged violations of pollution laws, Reuters reported Friday.

The EPA revealed that VW has been violating the Clean Air Act and could be subject to fines of as much as $18 billion. The German automaker has admitted using software in diesel cars that evades emission tests.

This week Volkswagen revealed that 11 million cars were fitted with engines that had shown a noticeable deviation in emissions levels between testing and road use, Reuters said.

The EPA letter puts auto manufacturers on notice that the agency may test or require testing of vehicles in an environment that would resemble normal driving conditions, the Wall Street Journal reported Friday.

The agency currently doesn’t conduct tests under real-word driving conditions, and requires automakers instead to submit design certificates for compliance, the paper said. The EPA’s random testing is conducted in a controlled environment.

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