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On March 22, 1975, the Tennessee Valley Authority (TVA) Browns Ferry Nuclear Plant (BFN) experienced a serious fire in their cable spreading room (CSR) and Unit 1 reactor building. The fire lasted over seven hours and damaged over 1,600 electrical cables, rendering all Unit 1 Emergency Core Cooling Systems inoperable. This near miss accident illustrated the vulnerability of essential electric cables to fire damage. In response to this fire, the United States Nuclear Regulatory Commission (NRC) issued Appendix R to Title 10 of the Code of Federal Regulations Part 50 (10 CFR 50) as a backfit to operating reactors and similar requirements implemented on reactors under construction. In order to comply with this new requirement, most operating United States (US) NPPs (NPPs) installed 1- or 3-hour Electrical Raceway Fire Barrier Systems (ERFBS) to protect electrical cables essential to Post-Fire Safe-Shutdown. At the time of initial installation, there were no definitive test standards for the ERFBS qualification. This resulted in most NPPs using the ERFBS to re-qualify/upgrade/change out their barriers. This report traces this history and how US NPPs returned their ERFBS to compliance.