14 C.F.R. § 121.253 Powerplant fire protection.
Title 14 - Aeronautics and Space
(a) Designated fire zones must be protected from fire by compliance with §§121.255 through 121.261. (b) Designated fire zones are— (1) Engine accessory sections; (2) Installations where no isolation is provided between the engine and accessory compartment; and (3) Areas that contain auxiliary power units, fuel-burning heaters, and other combustion equipment.
Title 14: Aeronautics and Space
PART 121—OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS
Subpart J—Special Airworthiness Requirements
§ 121.253 Powerplant fire protection.
