What Is an Emissions Test?
An emissions test is a required assessment of a vehicle’s pollution output under simulated normal driving conditions. Emissions tests are usually performed by auto mechanics in an auto mechanic shop. Vehicles are connected to a chassis dynamometer, which takes the car though various speed cycles that occur while driving. The dynamometer displays the revolutions per minute (RPM), horsepower, and torque of the engine while the wheels of the vehicle turn rollers located under them. An oxygen sensor measures the amount of pollution released by the car during the test.
At least 15 countries, including the United States, require vehicle emissions tests. Many countries follow similar protocols and have many of the same problems with vehicle emissions and testing. Since air pollution contributes to a decline in the health of a population, different countries often seek to reduce the amount of vehicle pollution that is released into the air. Vehicle emissions testing is designed to identify those vehicles that add too many pollutants to the air.
The Department of Motor Vehicles (DMV) in each state regulates emissions tests in the United States. The purpose of emissions testing in the US is to reduce air pollution by refusing to register vehicles that excessively pollute. Driving a car that has failed an emissions test can lead to a fine.
Cars emit the following pollutants into the air: nitrogen oxides, carbon monoxide, volatile organic compounds (VOCs), and fine particulate matter. These pollutants can damage the respiratory systems of people who are constantly exposed to them. By mandating an emissions test, DMVs aim to improve the respiratory health of individuals.
Although the emissions test is required by most states, it is easy for fraudulent testing to occur. Testers can choose to pass the non-passing vehicles by connecting the testing equipment to a passing car rather than the actual car that needs testing. As a result of improper testing, owners are able to operate their high-polluting vehicles on the road without penalty. These vehicles contribute to poor air quality in highly compact urban environments. Some emissions regulations are aimed at penalizing the owners of polluting vehicles.
Emissions tests help reduce air pollution. In urban cities with high traffic volume, lower emissions from cars help to reduce respiratory conditions. Cars that have fewer fumes emanating from them help to create a healthier breathing environment for urban populations. Rural or small town populations generally do not suffer from smog or unhealthy air quality. As a result, some small towns do not have emissions testing regulations.
In the US, the Environmental Protection Agency (EPA) is the federal agency that regulates vehicle emissions. Although this agency does not conduct emissions testing directly, the EPA does set the standards for vehicle emissions. In addition the EPA provides states with federal funding for low emission vehicle incentives and compliance programs.
Written by S. Crawford
