All fire extinguishers must be U.S. Coast Guard approved, fully charged, and readily accessible.  When looking for an extinguisher at a store or marine dealer, it is important to look for the words “U.S. Coast Guard Approved” right on the carton.   Although two sizes of extinguishers are approved for recreational craft (B-I or B-II), most extinguishers on the market will be B-I. The words “Marine Type USCG Type BC-Size I” will be in small letters right on the extin- guisher’s label along with the approval number. The letter “B” means the extinguisher will put out flammable liquid fires. The letter “C” means it can also be used for electrical fires.