14 CFR 29.609 - Protection of structure.
Each part of the structure must -
(a) Be suitably protected against deterioration or loss of strength in service due to any cause, including -
(2) Corrosion; and
(3) Abrasion; and
(b) Have provisions for ventilation and drainage where necessary to prevent the accumulation of corrosive, flammable, or noxious fluids.