Main objective of the recently started collaborative research project SFB/TR29 B4 is to provide cross-generational assistance to human operators working in industrial product-service systems (IPS(2)). By combining the ideas of action-specificity and multimodality a more immediate and purposeful reaction towards warnings is assumed. For this purpose, an action-specific warning system in form of a glove has been developed. It provides either visual, auditory or haptic feedback or a combination of all modalities. In a first study this prototype was compared with a conventional warning system, where multimodal devices were directly mounted to the machine. The test scenario used in this study is the 'changing of a spindle' on a replica of a micro milling machine. It was conducted with 42 participants. The experimental design is a within-design in terms of the two warning systems and a between-design concerning the three modalities and its combinations. Results of the two-way ANOVA with repeated measures on both factors 'system' and 'modality' show a significant main effect for the 'modality' and a significant interaction effect between both factors. Especially the haptic warnings on the action-specific glove were described as "that kind of warning, which evokes the fastest response".