The growing electrification and the integration of renewable energy in-crease the complexity of grid planning. This affects both grid utilization and power quality. Grid connections are therefore assessed by the distribution grid operators in accordance with the technical rules for the assessment of network disturbances DACHCZ. In this context, the assumed simultaneity of certain types of customer installations plays an important role. The lack of knowledge about simultaneity factors can lead to grid bottlenecks or unused reserve capacities. Therefore, the project analyzes the use of the new version 3 of the technical rules in co-operation with the distribution system operators as well as the applied methods and tools. The practice of assessing connection requests is compared with measurements in distribution grids. The project provides complementary recommendations for the assessment according to the technical rules. The results also include an open-source software tool to support connection assessment. In addition, reference values for simultaneity factors and utilization rates for different grid areas and types of installations are given to support a cost-efficient grid planning.