(a) The following materials must be self-extinguishing—

1. (1) Insulation on electrical wire and electrical cable;
2. (2) For levels 1, 2, and 3 airplanes, materials in the baggage and cargo compartments inaccessible in flight; and
3. (3) For level 4 airplanes, materials in the cockpit, cabin, baggage, and cargo compartments.

(b) The following materials must be flame resistant—

1. (1) For levels 1, 2 and 3 airplanes, materials in each compartment accessible in flight; and
2. (2) Any equipment associated with any electrical cable installation and that would overheat in the event of circuit overload or fault.

(e) For level 4 airplanes, each baggage and cargo compartment must—

1. (1) Be located where a fire would be visible to the pilots, or equipped with a fire detection system and warning system; and
2. (2) Be accessible for the manual extinguishing of a fire, have a built-in fire extinguishing system, or be constructed and sealed to contain any fire within the compartment.

(f) There must be a means to extinguish any fire in the cabin such that—

1. (1) The pilot, while seated, can easily access the fire extinguishing means; and
2. (2) For levels 3 and 4 airplanes, passengers have a fire extinguishing means available within the passenger compartment.

(g) Each area where flammable fluids or vapors might escape by leakage of a fluid system must—

1. (1) Be defined; and
2. (2) Have a means to minimize the probability of fluid and vapor ignition, and the resultant hazard, if ignition occurs.