Motor Vehicle Air Pollution Control Act

The Motor Vehicle Air Pollution Control Act is a 1965 amendment to the U.S. Clean Air Act of 1963. The amendment set the first federal vehicle emissions standards, beginning with the 1968 models. These standards were reductions from the 1963 emissions: 72% reduction for hydrocarbons, 56% reduction for carbon monoxide, and 100% reduction for crankcase hydrocarbons. The impact the regulatory standards will have on air quality in the future, as well as the potential characteristics of the vehicle fleet can be analyzed with the use of roadway air dispersion models.

The U.S. Environmental Protection Agency (EPA) is a department specific to the Clean Air Act. Its purpose is to make sure the amount of air pollution emitted stays inside the standards set by the U.S. Each state is required to have a state implementation plan (SIPs) that clearly indicates how it will enforce the regulations of the Clean Air Act. The states have to create regulations of their own that also adhere to the guidelines of the U.S. regulations; in order to do so, they must hold hearings so the public can contribute ideas and provide feedback.

The six common air pollutants of primary concern to the United States are particle pollution, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. These pollutants are detrimental to health, the environment, and a person's home and other belongings. The worst two of the six pollutants are particle pollution and ground-level ozone, which have to be regulated by the EPA. Particle pollution, or particle matter, consists of soot, smoke, and chemically formed "droplets". These particles are very small and can bury themselves deep inside the lungs. Ground-level ozone is found in smog and can also negatively affect the lungs. Smog contains volatile organic compounds (VOCs) and nitrogen oxides (NOx). VOCs come from cars burning gasoline, petroleum refineries, chemical manufacturing plants, etc., while NOx results from burning gasoline, coal, or oil.

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