A hand-held device and a method for plasma treatment of workpieces. The hand-held device comprises a housing for receiving a plasma source supplied with a gas stream from a gas supply unit. Further, an electrode unit is arranged in the plasma source and connected via an electrical line with a voltage source so that a plasma stream can be produced. The plasma stream can be directed through a nozzle of the housing onto a workpiece. The hand-held device comprises a sensor system for the collection of operating parameters which includes at least one operator sensor device for collecting a position of an operator relative to the plasma source and at least one pressure sensor for the collection of a pressure in the gas supply unit. Means of the hand-held device is communicatively connected with the sensor system for detecting the collected operating parameter via control data lines.