Exhaust system Law in the United States and other countries to not have a catalytic converter. Converters may not be removed from a vehicle that is used only for "off-road" driving in the United States. The main purpose of a catalytic converter on an automobile is to reduce harmful emissions of hydrocarbons, carbon monoxide and nitrogen oxides into the atmosphere. They work by transforming the polluted exhaust components into water and carbon dioxide. Cat-back (also cat back and catback) refers to the portion of the exhaust system from the outlet of the catalytic converter to the final vent to open air. This
Pollution prevention located near environmentally sensitive estuaries. These areas are particularly impacted by high levels of diesel exhaust, particulate matter, nitrogen oxides, ozone, and sulfur oxides. The solution for reducing port-related pollution is multi-fold, encompassing attainable alternatives and long-term reduction goals. Examples of simple steps include a restriction on engine idling for ships in the port and the use of cleaner grade diesel fuels. Some more expensive measures can be taken to mitigate the pollution of ships. Replacing older model ships with ships containing new engines allows the ships to meet modern emission standards. Exhaust systems can also be retrofitted in order