Appendix B: Summary of the Contribution of Transportation and Motor Vehicles to National Emissions of Each Pollutant

Contribution of Emissions by Vehicle Classisifcation Compared to Total Stationary and Mobile Sources (Thousand Short Tons, 2002)

Source of Category	NOx		CO		VOC		NH3		SO2		PM10		PM2.5
TOTAL ALL SOURCES	21,102		112,049		16,544		3,712		15,353		22, 54		6,803
MOBILE SOURCES TOTAL	11, 451	54.26%	86, 611	77.30%	7, 231	43.71%	290	7.81%	696	4.53%	515	2.32%	434	6.38%
HIGHWAY VEHICLES	7, 365	34.90%	62,161	55.48%	4,543	27.46%	287	7.73%	275	1.79%	204	0.92%	149	2.19%
Light-Duty Gas Vehicles & Motorcycles	2, 166	10.26%	34, 400	30.70%	2, 496	15.09%	184	4.96%	93	0.61%	52	0.23%	27	0.40%
Light-Duty Gas Trucks	1, 401	6.64%	24, 191	21.59%	1, 638	9.90%	92	2.48%	65	0.42%	30	0.14%	16	0.24%
Heavy-Duty Gas Vehicles	404	1.91%	2, 554	2.28%	201	1.21%	4	0.11%	12	0.08%	9	0.04%	7	0.10%
Diesels	3,395	16.09%	1, 016	0.91%	208	1.26%	6	0.16%	105	0.68%	113	0.51%	99	1.45%
OFF-HIGHWAY	4, 086	19.36%	24, 450	21.82%	2, 688	16.25%	3	0.08%	420	2.74%	311	1.40%	285	4.19%
Non-Road Gasoline	211	1.00%	21, 940	19.58%	2, 342	14.16%	1	0.03%	8	0.05%	72	0.32%	67	0.98%
Non-Road Diesel	1, 600	7.58%	872	0.78%	188	1.14%	2	0.05%	198	1.29%	169	0.76%	155	2.28%
Aircraft	81	0.38%	257	0.23%	21	0.13%	NA		8	0.05%	3	0.01%	2	0.03%
Marine Vessels	1, 011	4.79%	133	0.12%	32	0.19%	NA		160	1.04%	44	0.20%	40	0.59%
Railroads	889	4.21%	88	0.08%	35	0.21%	NA		47	0.31%	22	0.10%	20	0.29%
Other	295	1.40%	1, 160	1.04%	71	0.43%	0		0	0.00%	1	0.00%	1	0.01%
ROAD DUST	NA	NA	NA	NA	NA	NA	NA	NA	NA	NA	3,951	17.83%	694	10.05%

Source: National Emissions Inventory Air Pollutant Emissions Trends Data, http://www.epa.gov/ttn/chief/trends/index.html#tables