When necessary for safety, components that could accumulate significant amounts of combustible mixtures must be purged in accordance with a procedure which meets the provisions of the ``Purging Principles and Practices (incorporated by reference, see Sec. 193.2013)'' after being taken out of service and before being returned to service. [Amdt. 193-2, 45 FR 70405, Oct. 23, 1980, as amended by Amdt. 193-25, 80 FR 183, Jan. 5, 2015]