The U.S. Environmental Protection Agency (EPA) granted a waiver allowing up to 15 percent ethanol in gasoline. According to industry test data put out last October, E15 can cause significant damage to marine engines. A 2011 alternative fuel study executed by BRP, the National Marine Manufacturers Association (NMMA) and the American Boat and Yacht Council (ABYC) concluded that isobutanol was a promising alternative fuel in marine engines.