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CS 25.1183 Flammable fluid-carrying components

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

IRImplementing rule

CS 25.1183Flammable fluid-carrying components

(a)Except as provided in sub-paragraph (b) of this paragraph, each line, fitting, and other component carrying flammable fluid in any area subject to engine fire conditions, and each component which conveys or contains flammable fluid in a designated fire zone must be fire resistant, except that flammable fluid tanks and supports in a designated fire zone must be fireproof or be enclosed by a fireproof shield unless damage by fire to any non-fireproof part will not cause leakage or spillage of flammable fluid. Components must be shielded or located to safeguard against the ignition of leaking flammable fluid.

(b)Sub-paragraph (a) of this paragraph does not apply to –

(1)Lines, fittings and components which are already approved as part of a type certificated engine; and

(2)Vent and drain lines, and their fittings, whose failure will not result in, or add to, a fire hazard.

(c)All components, including ducts, within a designated fire zone must be fireproof if, when exposed to or damaged by fire, they could –

(1)Result in fire spreading to other regions of the aeroplane, or

(2)Cause unintentional operation of, or inability to operate, essential services or equipment.

IR · CS 25.1183 — 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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