Section 121.247 - Fire-wall constructionEach fire wall and shroud must-
(a) Be so made that no hazardous quantity of air, fluids, or flame can pass from the engine compartment to other parts of the airplane;(b) Have all openings in the fire wall or shroud sealed with close-fitting fire-proof grommets, bushings, or firewall fittings;(c) Be made of fireproof material; and(d) Be protected against corrosion.