Emissioncontrol

Vehicle emissions control is the study and practice of reducing the polluting emissions produced by vehicles powered by internal combustion engines.
The parts of a vehicle that are designed to reduce air pollution are called emission control systems. These systems focus on minimizing crankcase, evaporative, and tailpipe exhaust emissions. The first emission control systems were introduced in the late 1960s as vehicle add-ons. By 1971, the government mandated evaporative emission control systems on all U.S. vehicles. Four years later, the government began requiring auto makers to install catalytic converters, another emission control, on all new vehicles. In this post, we’ll explain more about the various types of emissions and how emission control systems work to reduce vehicle air pollution.
Types of Vehicle Emissions
Vehicles contribute to air pollution in three primary ways, all of which are outlined below.

Crankcase emissions. Unburned fuel and the byproducts of combustion reactions comprise crankcase emissions. The positive crankcase ventilation (PCV) system recirculates these gases back into the car’s engine where they reburn.
Evaporative emissions. Gasoline vapors emitted by the carburetor and fuel tank. By sealing the vehicle’s fuel system and keeping the vapors in a canister for reburning, these fumes are prevented from entering the atmosphere.
Tailpipe exhaust emissions. These emissions contain unburned hydrocarbons, carbon monoxide, and nitrogen oxides. Several emissions control systems minimize the creation of these pollutants, including the catalytic converter and special fuel calibration
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