A drain (or drains) must be provided to allow safe drainage of the oil system. Each drain must--
(a) Be accessible;
(b) Have drain valves, or other closures, employing manual or automatic shut-off means for positive locking in the closed position; and
(c) Be located or protected to prevent inadvertent operation. [Amdt. 23-29, 49 FR 6847, Feb. 23, 1984, as amended by Amdt. 23-43, 58 FR 18973, Apr. 9, 1993]