Vehicle Emissions & Air Pollution

vehicle emissions and air pollution

Millions of Americans rely on vehicles to meet their transportation needs, but vehicles are a big contributor to air pollution. As more information is discovered on the effects of passenger vehicle pollution, technology is being developed to make cars and other vehicles more environmentally friendly. The potential health issues caused by air pollution can be very serious, so finding a way to prevent the causes of pollution is important.

In the past few years, efforts to develop environmentally friendly cars have increased, leading to clean vehicles and fuel technology that have the potential to reduce vehicle related air pollution. This technology includes vehicles that are fuel efficient and use less oil, and ones that use cleaner fuels, resulting in fewer emissions being produced. Electric cars have also been developed, and do not produce any tailpipe emissions.

In addition to new technology that can reduce air pollution, there have been strong state and federal policies put into place. Vehicle emissions standards have been developed and since 1998, have helped to reduce pollution from cars and trucks by approximately 90 percent. The US Environmental Protection Agency has developed vehicle emissions standards and states have further developed their own laws regarding vehicle emissions.

When vehicles undergo an inspection, they also undergo emissions testing. The amount of pollution emitted by a particular vehicle and the speed at which it consumes fuel depend on a variety of factors. The EPA has developed models that provide estimates for the average emissions of different types of automobiles. Emissions testing has been set up based on these estimates and cars must pass emissions testing, however there are some exemptions to testing. Drivers should familiarize themselves with the specific vehicle emissions laws for their state of residence to ensure they are in compliance. Mechanics often have the tools necessary to perform emissions testing.

EPA "Tier 3" Standards

The Environmental Protection Agency's Tier 3 standards refer to a set of standards that were adopted in 2014. The standards are set to be implemented in 2017, and are expected to immediately start to reduce air pollution caused by vehicle emissions. The Tier 3 standards will effect vehicle manufacturers, who will be required to improve emission control technology, as well as oil companies, who will be required to decrease the sulfur content of gasoline, resulting in a cleaner burn. When implemented, the Tier 3 standards will significantly reduce vehicle related air pollution and will also benefit public health.

Major Air Pollutants

There are many things that contribute to air pollution, but some of the major pollutants include the following:

  • Carbon Monoxide (CO) is a colorless, odorless gas that is poisonous and is formed during the fuel combustion process.
  • Hydrocarbons (HC) are pollutants that form ground level ozone in the presence of sunlight, when they react with nitrogen oxides. Ground level ozone is one of the primary ingredients of smog.
  • Particulate Matter includes particles of metals and soot, and are what give smog its color. Particulate matter is very fine, and can penetrate the lungs, posing a threat to human health.
  • Nitrogen Oxides (NOx) are pollutants that can cause lung irritation and can lead to respiratory infections.
  • Sulfur Dioxide (SO2) is a pollutant caused by burning fuels that contain sulfur. It can react when released into the atmosphere, causing the formation of fine particles.

Now that scientists know more about the effects of vehicle emissions on the environment, work continues to be done to develop technology that helps to reduce pollution. Laws and standards that have been put into place regarding vehicle emissions have already helped to reduce air pollution, and more continues to be done. For more information on vehicle emissions and air pollution, visit the following pages.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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