Section 31.71 - Function and installation(a) Each item of installed equipment must-(1) Be of a kind and design appropriate to its intended function;(2) Be permanently and legibly marked or, if the item is too small to mark, tagged as to its identification, function, or operating limitations, or any applicable combination of those factors;(3) Be installed according to limitations specified for that equipment; and(4) Function properly when installed.(b) No item of installed equipment, when performing its function, may affect the function of any other equipment so as to create an unsafe condition.(c) The equipment, systems, and installations must be designed to prevent hazards to the balloon in the event of a probable malfunction or failure.Amdt. 31-4, 45 FR 60180, Sept. 11, 1980