Present firesafety measures were conceived to deal with hypothetical fires spreading by destruction of successive compartment boundaries. A new firesafety system, referred to as the "fire drainage system," is designed to cope with real-world fires spreading mainly by convection. It confines fire and smoke to the room of origin and to a small corridor element adjacent to the room. The system can be designed to operate without the use of water and electric energy. The fundamentals of its design are described and some experimental information is presented.