Atmospheric plasma spraying is a widely used coating process. The layer quality is determined by a large number of factors. Previous studies have focused on the influences of primary parameters, such as gas flows and electrical currents. In addition to these primary parameters, the process is influenced by a large number of disturbance variables, which lead to a fluctuation in the layer quality. Such disturbance variables can be wear of electrodes, irregularities in the cooling system or disruptions in powder injection. In this paper, the particle measurement system DPV-2000 and a F4-HBS gun are used to measure the influence of the noise factors during the atmospheric plasma spraying of aluminum oxide. The paper presents investigations on the influence of disturbance variables on an F4 burner (APS). Paper includes a German-language abstract.