High Quality Content by WIKIPEDIA articles! A fire hose is a high-pressure hose used to carry water or other fire retardant (such as foam) to a fire to extinguish it. Outdoors, it is attached either to a fire engine or a fire hydrant. Indoors, it can be permanently attached to a building`s standpipe or plumbing system. It was invented by Hero of Alexandria in the basis of Ctesibius` double action piston pump.