This part of ISO 16311 describes general requirements and procedures for the assessment of concrete structures. The assessment can be initiated under the following circumstances, but not limited to: a) an anticipated change in use or extension of design service life; b) structural deterioration due to time-dependent actions such as corrosion of reinforcement, fatigue, etc.; c) safety and/or serviceability check (e.g. for earthquake and increased traffic actions) as required by authorities, insurance companies, owners, etc.; d) structural damage by accidental actions. (See ISO 2394.) This part of ISO 16311 does not cover — qualification of personnel, — contractual matters, and — health and safety requirements for the protection of workers during the investigation and testing.