Before revision: NFPA 221, Standard for High Challenge Fire Walls, Fire Walls, and Fire Barrier Walls, 2009 Edition, section 3.3.14.6, NFPA 850-10 Fire Protection fotric Generating Plants and High Voltage DC Converter
After revision: .NFPA 221, Standard for High Challenge Fire Walls, Fire Walls, and Fire Barrier Walls, 2009 Edition, section 3.3.14.6, NFPA 850-10 Fire Protection fotric Generating Plants and High Voltage DC Converter