Heavy-duty vehicles account for approximately 30 percent of the oxides of nitrogen (NOx) and 65 percent of the particulate matter (PM) emissions from the entire California on-road fleet, despite the fact that these vehicles comprise only 2 percent of the same. To meet legislative mandates to reduce excess smoke emissions from in-use heavy-duty diesel-powered vehicles, the Air Resources Board (ARB or Board) adopted, in December 1997, amendments to the regulations governing the operation and enforcement of the Heavy-Duty Vehicle Inspection Program (HDVIP or the “roadside” program) and the Periodic Smoke Inspection Program (PSIP or the “fleet” program).
The initial roadside program was adopted in November 1990 in response to Senate Bill (SB) 1997 (stat. 1988, ch. 1544, Presley), and enforced from 1991 to 1993. It was suspended in October 1993, when the Board redirected staff to investigate reformulated fuels issues. The Board adopted the fleet program in December 1992, but until recently it had not been enforced. Enforcement of these amended programs commenced in the Spring/Summer of 1998.
Compared to having no heavy-duty vehicle inspection programs, the roadside and fleet programs with the amendments are expected to achieve the following emission reductions (in tons per day) of reactive organic gases (ROG), NOx and PM:
Diesel fuel consumption will be reduced by approximately 16.7 and 19.2 million gallons annually in 1999 and 2010, respectively. This represents a savings over the 12-year period of approximately 250 million gallons of fuel or over $212 million (at current fuel prices.)
Diesel fuel consumption will be reduced by approximately 16.7 and 19.2 million gallons annually in 1999 and 2010, respectively. This represents a savings over the 12-year period of approximately 250 million gallons of fuel or over $212 million (at current fuel prices.)