Text in force at 23-63: from 23-51, effective 12 Mar 1996.
Designated fire zones are--
(a) For reciprocating engines--
(1) The power section;
(2) The accessory section;
(3) Any complete powerplant compartment in which there is no isolation between the power section and the accessory section.
(b) For turbine engines--
(1) The compressor and accessory sections;
(2) The combustor, turbine and tailpipe sections that contain lines or components carrying flammable fluids or gases.
[(3) Any complete powerplant compartment in which there is no isolation between compressor, accessory, combustor, turbine, and tailpipe sections.]
(c) Any auxiliary power unit compartment; and
(d) Any fuel-burning heater, and other combustion equipment installation described in Sec. 23.859.
61 FR 5138 · Source