Clean Air Act §202(a)(1) gives EPA authority to establish emissions standards for “any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines.” This authority extends to both light and heavy duty vehicles. The most recent set of particulate matter standards for light-duty vehicles was promulgated in 2014, called Tier 3 standards. As Tier 3 are phased in from 2017-21, they should have a substantial effect on black carbon emissions. emissions standards required diesel particulate filters.