Contactless detection of human limbs at manually-fed machines or robot workplaces is a desirable feature for safety applications. Both manually-fed machines and robots are often equipped with potentially dangerous moving parts that are difficult to shield off from the reach of the user. Therefore, robot workplaces are often caged in completely and the robot is stopped while there are people within the cage, making it impossible for humans to work together "hand in hand" with the robot in a so-called joint-action scenario. On manually-fed machines such as bench saws or presses, this is no feasible solution as well, as productive working requires the user to be near the machine at all time, rendering these machines very prone to accidents (see Reinert et al. 2009).