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Personal water craft


A personal watercraft is a recreational watercraft that the rider sits or stands on, rather than inside of, as in a boat. Models have an inboard engine driving a pump jet. They are often referred by the name Jetski, which is in fact a brand name owned by Kawasaki.

Most are designed for two or three people, though four-passenger models exist.

PWCs powered by two-stroke engines cause remarkable amounts of air and water pollution because of their inefficiency, and because they vent their exhaust underwater. Four-stroke engines are somewhat better as they do not burn as much lubricating oil. According to the Surfrider Foundation , operating a 2-stroke 100-HP PWC for one hour produces as much air pollution as operating a car for ten years (130,000 miles). In addition, the Bluewater Network estimates that "US waters will be polluted with 20 billion pounds of hydrocarbons from now until 2051 - an amount equivalent to 300 Exxon Valdez disasters," due to motorized pleasure craft including PWCs and outboard motors. The hydrocarbons form oxygen-blocking films and otherwise harm the entire food chain.


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01-04-2007 01:18:14
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