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Green Vehicle Guide

Vehicles and Greenhouse Gases - EPA’s Role

At EPA, our team of engineers, scientists, policy analysts, lawyers, and others work together to ensure that cars and trucks on the road are as clean and efficient as possible.  We do this because we know that cleaner vehicles mean cleaner air.

Here are just some of the vehicle-related projects that we're working on:

Find out how EPA engineers test new vehicles for emissions and fuel economy
Learn about our regulations that limit emissions from new vehicles
Learn how fuel-efficient technology innovations are transforming the automotive market
Explore trends in greenhouse gas emissions from U.S. transportation
SmartWay vehicles