A method for fire-fighting, a rescue boom and a nozzle of a piercing tool. A rescue boom is provided with an elongated piercing tool that can be pushed through a shell of a burning object. A fire extinguishing medium can be conveyed through the piercing tool to a nozzle provided in the piercing tool. The nozzle is provided with orifices arranged such that single jets form a single uniform jet having a flat curtain-like shape.
