California Air Resources Board

CARB identified particulate emissions from diesel-fueled engines (diesel PM) as toxic air contaminants  in August 1998. Following its identification and pursuant to the Toxic Air Contaminant Identification and Control Act (AB 1807, Tanner 1983), CARB determined the need and degree to further control diesel PM.  With the participation of local air districts, industry, and interested public, CARB prepared a risk management guidance document and a risk reduction plan to inform the regulatory process and achieve further diesel PM emission reductions.