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U.S. Department of Energy
Office of Scientific and Technical Information

Revised heavy duty engine regulations for 1979 and later model years

Journal Article · · Fed. Regist. (Wash., D.C.); (United States)
OSTI ID:7353127
Standards are proposed beginning with the 1979 model year for both gasoline-fueled and Diesel heavy duty engines of 1.5 gms/BHP-hr. hydrocarbon (HC), 25 gms/BHP-hr. carbon monoxide (CO), and 10 gms/BHP-hr. hydrocarbon plus oxides of nitrogen (HC + NOx). Current standards are 16 gms/BHP-hr.HC + NOx and 40 gms/BHP-hr. CO without a separate HC requirement. Additionally, a Diesel engine peak smoke opacity standard of 35 percent instead of the present 50 percent standard is proposed to prevent degradation in on the road smoke levels as a result of changes in gaseous emissions standards. Nearly all currently certified engine families have demonstrated smoke levels at or below 35 percent peak opacity. Acceleration and lugging mode Diesel smoke standards of 20 and 15 percent are unchanged by the proposal. Test procedure revisions include the substitution of more accurate instrumentation for measurement of gasoline-fueled engine HC and both gasoline-fueled and Diesel NOx measurements; the addition of specific calibrations and maintenance procedures; and minor revisions to the test cycles.
OSTI ID:
7353127
Report Number(s):
40CFR86
Journal Information:
Fed. Regist. (Wash., D.C.); (United States), Journal Name: Fed. Regist. (Wash., D.C.); (United States) Vol. 41:101; ISSN FEREA
Country of Publication:
United States
Language:
English