This paper analyzes the principles and methods for the repair and protection of high-strength concrete floors in accordance with Part 9 of the EN 1504 standard. The study outlines six key principles for addressing concrete defects — protection against ingress, moisture control, concrete restoration, structural strengthening, physical resistance, and resistance to chemicals — and five principles for mitigating steel reinforcement corrosion, including preserving or restoring passivity, increasing resistivity, cathodic control, cathodic protection, and control of anodic areas. The selection of appropriate repair and protection strategies depends on the type of structure, environmental exposure, operational use, and maintenance strategy. The proposed framework emphasizes the adaptation of repair and protection measures to the specific conditions and requirements of each project, ensuring structural safety, extended service life, and compliance with international technical standards. This approach provides a systematic basis for maintaining the performance and durability of industrial and civil flooring systems.