Abstract: A tool and a method for cutting holes in a container wall such as in a tank, a cistern, a pipeline, a vehicle, a ship, a production like or the like that contains inflammable, explosive, or other hazardous gasses, and liquids. The tool includes means for pressurising a cutting medium and discharging said medium via a nozzle. The nozzle is arranged in an enclosing cover including a scalable safety outlet for evacuation of the container contents. The cover has means of sealed-off abutment against the container wall concerned in the area in which hole cutting is to be performed. The nozzle is arranged to be directed towards the container wall in such a way that in use the cutting medium is discharged in the form of a jet impinging against the container wall with sufficient force to cut through said wall.