BTS | Table 4-38: Estimated National Average Vehicle Emissions Rates per Vehicle by Vehicle Type using Gasoline and Diesel

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Table 4-38: Estimated National Average Vehicle Emissions Rates per Vehicle by Vehicle Type using Gasoline and Diesel

(Grams per mile)

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	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007
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	0.61	0.52	0.46	0.42
Nonexhaust HC	1.21	1.17	1.12	1.09	1.07	1.05	1.03	1.01	0.98	0.95	0.91	0.88	0.84	0.81	0.77	0.72	0.68	0.62
Total HC	4.00	3.67	3.35	3.07	2.84	2.62	2.41	2.26	2.12	2.00	1.88	1.77	1.65	1.54	1.37	1.25	1.13	1.04
Exhaust CO	42.89	39.15	35.54	32.23	29.32	26.60	24.18	22.38	20.86	19.54	18.53	17.80	16.98	16.14	13.79	12.57	10.87	10.28
Exhaust NO_x	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	1.00	0.92	0.79	0.73
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	0.96	0.78	0.69	0.64
Nonexhaust HC	1.37	1.30	1.21	1.17	1.13	1.11	1.08	1.05	1.02	1.00	0.98	0.95	0.90	0.84	0.80	0.76	0.71	0.66
Total HC	5.05	4.63	4.21	3.88	3.59	3.32	3.04	2.85	2.68	2.54	2.43	2.30	2.14	1.98	1.76	1.54	1.40	1.31
Exhaust CO	56.23	51.99	47.93	44.34	40.77	37.51	34.47	32.20	30.23	28.28	26.81	25.43	23.85	21.51	18.76	16.23	14.33	13.52
Exhaust NO_x	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	1.32	1.21	1.09	1.02
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	0.73	0.64	0.53	0.48
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	1.35	1.24	1.14	1.07
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	2.08	1.88	1.67	1.54
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	18.46	16.73	14.51	13.55
Exhaust NO_x	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	4.62	4.28	3.73	3.33
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	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	0.69	0.69	0.69	0.68
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	2.31	2.30	2.30	2.29
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	14.59	14.58	14.59	14.59
Exhaust NO_x	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	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	0.60	0.58	0.48	0.36
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	1.59	1.57	1.41	1.21
Exhaust NO_x	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	1.43	1.32	1.11	0.85
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	0.98	0.80	0.79	0.63
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	1.68	1.37	1.34	1.06
Exhaust NO_x	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	1.59	1.37	1.30	1.09
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	0.58	0.54	0.51	0.48
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	3.19	3.05	2.90	2.66
Exhaust NO_x	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	12.50	11.45	10.55	9.60
Average Emissions Per Vehicle, RFG and Diesel Fleet
Exhaust HC	2.98	2.70	2.42	2.18	1.96	1.76	1.56	1.43	1.32	1.23	1.16	1.08	0.99	0.91	0.77	0.65	0.581	0.543
Nonexhaust HC	1.21	1.16	1.10	1.06	1.04	1.01	0.99	0.97	0.94	0.91	0.89	0.86	0.82	0.77	0.74	0.69	0.65	0.604
Total HC	4.20	3.86	3.52	3.24	3.00	2.77	2.55	2.40	2.26	2.14	2.04	1.93	1.81	1.68	1.51	1.35	1.23	1.147
Exhaust CO	45.07	41.43	37.93	34.76	31.84	29.12	26.65	24.90	23.40	22.00	20.94	20.02	18.94	17.49	15.24	13.56	11.95	11.318
Exhaust NO_x	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	2.25	2.07	1.87	1.726

KEY: CO = carbon monoxide; HC = hydrocarbon; NO_x = 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 ºF, daily temperature range 60-84 ºF, 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.

Average emissions per vehicle rates assume a fleet comprised exclusively of gasoline and diesel vehicles. For emissions estimates of a fleet using RFG and diesel, see table 4-39.

SOURCE

U.S. Environmental Protection Agency, National Vehicle and Fuel Emissions Laboratory, personal communication, Nov. 29, 2007.