This document specifies performance requirements for cathodic protection of steel in cement-based concrete, in both new and existing structures. It covers building and civil engineering structures, including carbon steel reinforcement and prestressed reinforcement embedded in the concrete. It is applicable to uncoated steel reinforcement and to organic-coated steel reinforcement. It is not applicable to reinforced concrete containing electrically conductive fibres (e.g. carbon or steel). This document applies to steel embedded in atmospherically exposed, buried, immersed and tidal elements of buildings or structures. This document is only applicable to the applications of cathodic protection to steel in concrete which are designed with the intention to, and can be demonstrated to, meet the criteria of protection specified in 8.6. This requires the provision of sufficient performance monitoring systems as specified in 6.3 to all parts of the structure intended to be protected, in order to assess the extent to which the criteria in 8.6 are met. This document does not apply to galvanic anodes or systems applied into patch repairs to reduce the effects of ‘incipient anodes’. This document does also not apply to any form of cathodic protection systems or other electrochemical treatments that either cannot meet the requirements of 8.6 or are not provided with the performance monitoring systems (see 6.3) that are necessary to assess whether the criteria of protection specified in 8.6 are met. NOTE 1 Annex A gives guidance on the principles of cathodic protection and its application to steel in concrete. NOTE 2 This document, while not specifically intended to address cathodic protection of steel in any electrolyte except concrete, can be applied to cathodic protection of steel in other cementitious materials such as are found, for example, in early 20th century steel-framed masonry, brick and terracotta clad buildings. In such applications, additional considerations specific to these structures are required in respect of design, materials and installation of cathodic protection; however, the requirements of this document can be applied to these systems.