ISO 1 2944-3: 2017 specifies the design requirements for effective corrosion protection of steel structures through protective coatings systems. The standard provides detailed guidance on designing steel structures for long-lasting corrosion protection, covering all aspects from design to maintenance. Emphasis includes how to choose the appropriate Coating system, surface preparation, Coating application requirements and checking maintenance measures. The new version has updated terminology, references and further clarification of design details compared to the old version to ensure the effectiveness and long-term durability of protective measures. The standard aims to provide structural designers, Coating manufacturers and maintenance personnel with comprehensive design and implementation guidelines to optimize the corrosion protection performance of steel structures.