Knowledge rules development for diagnostics outcomes in GIS

In GIS, the diagnostic outcomes have to be interpreted in a structural way to support maintenance decisions. Therefore criteria or knowledge rules are required. In this contribution, the following questions have been answered: 1. Which components have to be diagnosis? 2. Which diagnostic methods have to be used? 3. How to interpret the diagnostic outcomes to estimate the components actual condition? The criticality of the GIS components has been determined. The critical components in GIS get the highest priority to be diagnosed. Thereafter, diagnostic methods which are required to prevent failures with unacceptable risk level in GIS are distinguished. Finally, knowledge rules are developed to interpret the diagnostics outcomes.