The Environmental Protection Agency (EPA) has partially disapproved a California regulation that imposes stringent vehicle emission standards on heavy-duty vehicles running in the state irrespective of where these vehicles were registered, the agency said in a Jan. 27 statement.
At issue is California’s Heavy-Duty Inspection and Maintenance (I/M) Regulation under the Clean Air Act (CAA). The regulation mandates heavy-duty vehicles undergo periodic testing and meet other compliance requirements to ensure their emission control components are not malfunctioning, according to the California Air Resources Board (CARB).
