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KEY: NA = not applicable; R = revised.
Very large urban areas - 3 million and over population.
Large urban areas - 1 million to less than 3 million population.
Medium urban areas - 500,000 to less than 1 million population.
Small urban areas - less than 500,000 population.
KEY: NA = not applicable; R = revised.
Very large urban areas – 3 million and over population.
Large urban areas – 1 million to less than 3 million population.
Medium urban areas – 500,000 to less than 1 million population.
Small urban areas – less than 500,000 population.
a Rank is based on the calculated point change with the highest number corresponding to a rank of 1.
b Average weighted by vehicle miles traveled in city.
KEY: NA = not applicable; R = revised.
Very large urban areas – 3 million and over population.
Large urban areas – 1 million to less than 3 million population.
Medium urban areas – 500,000 to less than 1 million population.
Small urban areas – less than 500,000 population.
a Percent changes were calculated using the numbers in this table and were not obtained from the source. Rank is based on the calculated percent change with the highest number corresponding to a rank of 1.
KEY: cc = cubic centimeters; g = gram; HC = hydrocarbon; CO = Carbon Monoxide; kg = kilogram; km = kilometer; lb = pound; mi = miles; mph = miles per hour; NOx = Nitrogen Oxides.
a A motorcycle is any motor vehicle with a headlight, taillight, and stoplight, and having two or three wheels and a curb mass less than or equal to 793 kg (1,749 lb). (The limit was 680 kg, or 1,499 lb prior to the 1998 model year.) A motorcycle is excluded from the standards if it has a displacement of less than 50 cc (3.1 cubic inches) or if with a 80 kg (176 lb) driver it cannot start...
KEY: CO = carbon monoxide; HC = hydrocarbon; NOx = nitrogen oxides; NMHC = nonmethane hydrocarbons.
a Smoke opacity is expressed in percentage for acceleration, lugging, and peak modes (acceleration/lugging/peak). Lugging is when a vehicle is carrying a load.
b Gross vehicle weight rating (GVWR) is the maximum design loaded weight.
c Several testing procedures have been used during the course of exhaust emissions control. A steady-state 9-mode test procedure (13-mode for diesel) was used for 1970-83 standards. For 1984, either...
KEY: CO = carbon monoxide; HC = hydrocarbon; NOx = nitrogen oxides; NMHC = nonmethane hydrocarbons; NMOG = nonmethane organic gas; HCHO = formaldeyhyde.
a Smoke opacity is expressed in percentage for acceleration, lugging, and peak modes (acceleration/lugging/peak). Lugging is when a vehicle is carrying a load.
b Gross vehicle weight rating (GVWR) is the maximum design loaded weight.
c Several testing procedures have been used during the course of exhaust emissions control. A steady-state 9-mode test procedure (13-mode...
KEY: CO = carbon monoxide; g/bhp-hr = grams per brake horsepower/hour; GVWR = gross vehicle weight rating; HC = hydrocarbons; NMHC=nonmethane hydrocarbon; NMOG = nonmethane organic gases; NOx = nitrogen oxides.
a The MDPV category was created for the Interim Tier 2 and Tier 2 vehicle emissions standards. This category was specifically designed to help bring passenger vehicles (such as large sport utility vehicles and passenger vans) over 8,500 pounds GVWR into the Tier 2 program. MDPVs are defined as any complete heavy-duty vehicle less than 10,000 pounds GVWR...
KEY: ALVW=adjusted loaded vehicle weight; CO = carbon monoxide; GVWR=gross vehicle weight rating; HC = hydrocarbons; NMHC=nonmethane hydrocarbon; NMOG=nonmethane organic gases; NOx=nitrogen oxides.
a Light-duty truck categories LDT1-LDT4 were not created until 1994. From 1968 to 1978 all trucks with a GVWR up to 6,000 pounds were classified as light-duty trucks and were required to meet the same standards. As of 1979, the maximum weight was raised to 8,500 pounds GVWR. During 1988-93, light-duty trucks were divided into two subcategories that coincide...
KEY: CO=carbon monoxide; GVWR=gross vehicle weight rating; HC=hydrocarbons; LVW=loaded vehicle weight; NMHC=non-methane hydrocarbons; NMHC=nonmethane hydrocarbons; NMOG=nonmethane organic gases; NOx=nitrogen oxides.
a Light-duty truck categories LDT1-LDT4 were not created until 1994. From 1968 to 1978 all trucks with a GVWR up to 6,000 pounds were classified as light-duty trucks and were required to meet the same standards. As of 1979, the maximum weight was raised to 8,500 pounds GVWR. During 1988-93, light-duty trucks were divided into two...
KEY: CO=carbon monoxide; CVS = constant volume sampler; GVWR=gross vehicle weight rating; HC=hydrocarbons; LVW=loaded vehicle weight; NMHC=nonmethane hydrocarbons; NMOG= nonmethane organic gases; NOx=nitrogen oxides.
a Light-duty truck categories LDT1-LDT4 were not created until 1994. From 1968 to 1978, all trucks with a GVWR up to 6,000 pounds were classified as light-duty trucks and were required to meet the same standards. As of 1979, the maximum weight was raised to 8,500 pounds GVWR. During 1988-93, light duty trucks were divided...