This code provides the minimum requirements for the evaluation, repair, rehabilitation, and strengthening of existing concrete buildings and, where applicable, in nonbuilding structures. The code is comprised of both prescriptive and performance requirements. Commentary is provided for both the prescriptive and performance requirements and is intended to provide guidance to the licensed design professional and referenced sources for additional information the material presented in the code provisions. The code and commentary is intended for use by individuals who are competent to evaluate the significance, limitations of its content and recommendations, and who will accept responsibility for the application of the material it contains. The materials, processes, quality control measures, and inspections described in this document should be tested, monitored, or performed as applicable only by individuals holding the appropriate ACI Certifications or equivalent.