NFPA 851 provides fire prevention and fire protection recommendations to safeguard physical property and insure continuity of power production. This document is intended to provide guidance for those charged with the design, construction, and operation of hydroelectric generating plants. General plant design and fire protection systems are covered as well as identification and protection of hazards. New recommendations for the protection of generator pit and windings using thermoplastic materials are included. In addition, Chapter 2 has been completely revised to expand Administrative Controls to Fire Risk Control Program.