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Transportation Air Quality Selected Facts and Figures


Purpose and Terms

Overview/Transportation and Air Quality

Air Pollutants

Nonattainment Areas

Progress in Reducing Motor Vehicle Emissions

Travel Trends

Roads and Spending

Traffic Congestion

Emissions Sources

Emissions Trends

Air Quality Trends

Mobile Source Air Toxics

Greenhouse Gas Emissions

Emissions Standards

Vehicle Emissions

Policy Responses


Updated: 3/17/2015
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