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Table 4-38: Estimated National Average Vehicle Emissions Rates by Vehicle Type and Fuel (Grams per mile)R

Wednesday, November 21, 2012

Table 4-38: Estimated National Average Vehicle Emissions Rates by Vehicle Type and Fuel (Grams per mile)R

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  1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003
GASOLINE (assuming zero RFG)                            
Light-duty vehicles                            
Exhaust HC 2.79 2.50 2.23 1.98 1.77 1.57 1.39 1.25 1.14 1.05 0.97 0.89 0.81 0.74
Nonexhaust HC 1.21 1.16 1.12 1.09 1.07 1.05 1.03 1.01 0.98 0.95 0.92 0.88 0.84 0.81
Total HC 3.99 3.66 3.35 3.07 2.84 2.62 2.41 2.26 2.12 2.00 1.89 1.77 1.65 1.54
Exhaust CO 42.89 39.15 35.54 32.23 29.32 26.60 24.18 22.38 20.86 19.54 18.53 18.03 17.58 17.13
Exhaust NOx 2.70 2.47 2.27 2.09 1.94 1.78 1.64 1.55 1.46 1.35 1.29 1.25 1.20 1.14
Light-duty trucks                            
Exhaust HC 3.68 3.33 3.00 2.71 2.45 2.21 1.96 1.80 1.65 1.54 1.45 1.35 1.24 1.13
Nonexhaust HC 1.36 1.29 1.20 1.16 1.12 1.10 1.07 1.04 1.02 0.99 0.97 0.94 0.89 0.84
Total HC 5.04 4.62 4.20 3.87 3.58 3.31 3.03 2.85 2.67 2.53 2.42 2.29 2.13 1.98
Exhaust CO 56.23 51.99 47.93 44.34 40.77 37.51 34.47 32.20 30.23 28.28 26.81 25.61 24.32 22.30
Exhaust NOx 2.62 2.42 2.26 2.11 1.98 1.84 1.73 1.65 1.59 1.55 1.54 1.53 1.50 1.45
Heavy-duty vehicles                            
Exhaust HC 3.66 3.34 3.03 2.76 2.39 2.16 1.94 1.73 1.51 1.35 1.22 1.09 0.98 0.82
Nonexhaust HC 2.74 2.60 2.34 2.25 2.16 2.07 1.97 1.87 1.79 1.69 1.62 1.54 1.48 1.41
Total HC 6.40 5.94 5.37 5.00 4.55 4.24 3.91 3.60 3.29 3.04 2.84 2.63 2.46 2.24
Exhaust CO 85.61 78.64 72.12 65.92 60.01 54.16 48.52 43.26 38.82 34.54 31.08 27.59 24.73 20.60
Exhaust NOx 7.19 6.96 6.72 6.52 6.35 6.11 5.89 5.73 5.56 5.40 5.26 5.13 5.01 4.91
Motorcycles                            
Exhaust HC 2.01 1.88 1.82 1.75 1.72 1.69 1.63 1.63 1.62 1.61 1.61 1.61 1.61 1.61
Nonexhaust HC 0.74 0.73 0.72 0.72 0.71 0.71 0.70 0.69 0.70 0.70 0.70 0.70 0.70 0.70
Total HC 2.74 2.60 2.54 2.46 2.43 2.40 2.34 2.32 2.32 2.31 2.31 2.31 2.31 2.31
Exhaust CO 15.15 14.78 14.77 14.76 14.76 14.67 14.59 14.59 14.59 14.59 14.59 14.59 14.59 14.59
Exhaust NOx 1.26 1.28 1.28 1.28 1.28 1.26 1.25 1.25 1.25 1.25 1.25 1.25 1.25 1.25
DIESEL                            
Light-duty vehicles                            
Exhaust HC 0.68 0.69 0.71 0.73 0.75 0.77 0.79 0.81 0.81 0.82 0.80 0.76 0.73 0.73
Exhaust CO 1.49 1.52 1.56 1.60 1.64 1.69 1.73 1.76 1.78 1.79 1.78 1.75 1.73 1.74
Exhaust NOx 1.83 1.85 1.86 1.87 1.89 1.89 1.89 1.88 1.86 1.85 1.81 1.72 1.62 1.54
Light-duty trucks                            
Exhaust HC 1.59 1.60 1.64 1.64 1.68 1.67 1.69 1.63 1.51 1.42 1.02 0.88 0.96 0.97
Exhaust CO 2.67 2.70 2.76 2.77 2.85 2.85 2.89 2.79 2.60 2.44 1.77 1.54 1.66 1.68
Exhaust NOx 2.71 2.66 2.62 2.56 2.53 2.46 2.42 2.31 2.17 2.07 1.76 1.64 1.67 1.66
Heavy-duty vehicles                            
Exhaust HC 2.21 1.97 1.74 1.55 1.38 1.23 1.10 1.00 0.92 0.85 0.79 0.74 0.69 0.61
Exhaust CO 10.06 9.22 8.43 7.71 7.00 6.32 5.73 5.23 4.80 4.43 4.10 3.82 3.58 3.37
Exhaust NOx 23.34 22.14 21.47 21.10 20.75 20.49 20.24 20.04 19.84 19.14 18.05 16.68 15.52 13.92
AVERAGE OF ALL VEHICLES, GASOLINE AND DIESEL                            
Exhaust HC 2.98 2.70 2.42 2.18 1.96 1.76 1.56 1.43 1.32 1.23 1.15 1.08 0.99 0.91
Nonexhaust HC 1.21 1.15 1.09 1.06 1.03 1.01 0.99 0.96 0.94 0.91 0.88 0.85 0.81 0.77
Total HC 4.19 3.85 3.52 3.24 2.99 2.77 2.55 2.40 2.25 2.14 2.04 1.93 1.80 1.68
Exhaust CO 45.07 41.43 37.93 34.76 31.84 29.12 26.65 24.90 23.40 22.00 20.94 20.20 19.42 18.27
Exhaust NOx 4.15 3.92 3.75 3.61 3.49 3.36 3.24 3.18 3.12 3.02 2.91 2.78 2.65 2.48

KEY: CO = carbon monoxide; HC = hydrocarbon; NOx = nitrogen oxide; RFG = reformulated gasoline.

NOTES

As of July 1 of each year. Vehicles types are defined as follows: light-duty vehicles (passenger cars up to 6,000 lb GVWR); light-duty trucks (pickups and minivans up to 8,500 lb GVWR); heavy-duty vehicles (8,501 lbs or more GVWR); motorcycle (highway only). This table is based on MOBILE6, the U.S. Environmental Protection Agency's (EPA) latest highway vehicle emissions factor model. Interested readers can learn more about the MOBILE6 model at the following USEPA Internet site http://www.epa.gov/otaq/m6.htm.

Emissions factors are national averages based on the following assumptions: ambient temperature 75 F, daily temperature range 60-84 F, average traffic speed 27.6 mph (representative of overall traffic in urban areas), standard operating mode (cold-start, hot-start, stabilized), vehicle-miles traveled fractions, no inspection/maintenance or antitampering programs, and gasoline volatility 9.0 per square inch RVP (Reid vapor pressure).

See Table 4-39 for emissions from vehicles operating on reformulated gasoline.

Data for nonexhaust HC is negligible for diesel light-duty vehicles, light-duty trucks, and heavy-duty vehicles.

SOURCE

U.S. Environmental Protection Agency, National Vehicle and Fuel Emissions Laboratory, personal communications, July 31, 2002 and Nov. 26, 2003.