<P> In some areas, such as Lake Tahoe, All outboard motors and PWCs are permitted if they meet the 2006 EPA regulations . A number of pre-2006 model year PWC meet that EPA standard . </P> <P> Environmental groups such as the Surfrider Foundation and the Bluewater Network claim that more rapid progress could be made, and that the diminishing numbers of pre-1998 watercraft in use continue to emit substantial pollution . </P> <P> Against this, industry groups such as the Personal Watercraft Industry Association point out that environmental groups continue to cite pollution levels of pre-regulation watercraft and ignore the improvements made to newer models; and furthermore, that personal watercraft are unfairly singled out when they are no more polluting than other powered boats . </P> <P> Apart from the obvious hazards of collisions and mechanical breakdowns common to all vehicles, operating or riding a PWC can involve a risk of orifice injuries . These injuries are typical of the kinds of injuries that waterskiers experience as a result of falling into the water at speed . Such injuries can occur from simply falling in the water at speed or they can occur from the output end of the pump jet . A rider who falls (or is ejected) off the back can land directly in the path of the PWC's high - pressure jet of water . Unless a rider is appropriately dressed in garments made out of a strong, thick substance like neoprene (as is commonly found in wetsuits), the jet may penetrate any orifice it reaches . All major PWC manufacturers warn about this risk and recommend that passengers wear wet suit bottoms or equivalent protection . The American Waterski Racing Association recommends that all of their racers wear wet suit bottoms for this same reason . </P>

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