04.04. Residential / Commercial and Industrial Buildings, Category 1 (04.04), 04.05. Power Supply (Internal and External Power Supply and Lighting Networks / Power Supply Systems / Photovoltaic and Wind Power Plants), Category 2 (04.05), 04.06. HVAC / Gas Supply, Category 2 (04.06), 04.07. Hydraulic Structures, Category 2 (04.07), 04.08. Water Supply and Drainage / Melioration Systems, Category 2 (04.08)