Exhaust gas pollution exhaust sources in various large-scale industrial facilities such as petroleum refineries, natural gas processing plants, petrochemical plants and chemical production plants. However, these are often referred to as flue gases. Catalytic converters in cars intend to break down the pollution of exhaust gases using a catalyst. Scrubbers in ships intend to remove the sulfur dioxide (SO) of marine exhaust gases. The regulations on marine sulfur dioxide emissions are tightening, however only a small number of special areas worldwide have been designated for low sulfur diesel fuel use only. One of the advantages claimed for advanced steam technology engines is
Exhaust system tandem with smog abatement legislation rendered lake pipes, as a bona fide performance prerequisite, obsolete. No meaningful performance gain to be had for contemporary vehicles, lake pipes persist into the 21st century as a superfluous, retrograde aesthetic, usually chrome plated with various options, allowing the driver to control whether exhaust gas is routed the standard exhaust system, or through lake pipes, which are commonly fashioned by laker caps which, affixed by fasteners at the terminal end of exhaust tips, serve to (1) "cap" the exhaust system when not in use, and/or (2) signal authorities that the presence of lake pipes