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CS 25.1181 Designated fire zones: regions included

Large Aeroplanes (CS-25) · CS-25 · EAR revision 26 Jan 2023

IRImplementing rule

CS 25.1181Designated fire zones: regions included

(See AMC 25.1181.)

(a)Designated fire zones are –

(1)The engine power section;

(2)The engine accessory section;

(3)Any complete powerplant compartment in which no isolation is provided between the engine power section and the engine accessory section;

(4)Reserved.

(5)Any fuel-burning heater and other combustion equipment installation described in CS 25.859;

(6)The compressor and accessory sections of turbine engines; and

(7)Combustor, turbine, and tailpipe sections of turbine engine installations that contain lines or components carrying flammable fluids or gases.

(b)Each designated fire zone must meet the requirements of CS 25.863, 25.867, 25.869, and 25.1185 to 25.1203

IR · CS 25.1181 — CS-25 · ED Decision 2003/2/RM · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

AMCAcceptable means of compliance

AMC 25.1181Designated fire zones

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1 ISO 2685, (15 JULY 1992) ‘Aircraft – Environmental conditions and test procedures for airborne equipment – Resistance to fire in designated fire zones’, gives test conditions and methods of demonstrating compliance with the ‘Fire-resistant’ and ‘Fireproof’ requirements. 2 Tests to demonstrate compliance with the standard grades of resistance to fire may not be necessary if similarity can be shown with other components which have been tested in accordance with this standard. 3 For example, materials which are considered satisfactory for use in firewalls without being subjected to fire tests include – a. Stainless steel sheet 0·4 mm (0·016 in) thick; b. Mild steel sheet protected against corrosion 0·45 mm (0·018 in) thick; and c. Titanium sheet 0·45 mm (0·018 in) thick.

AMC · AMC 25.1181 — CS-25 · ED Decision 2003/2/RM · CS-25 Easy Access Rules · EAR revision 26 Jan 2023

All rules in SUBPART E – POWERPLANT

Consolidated from the EASA Easy Access Rules (revision 26 Jan 2023, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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