Every person employed or engaged to maintain GMDSS equipment at sea, when the service of a person so designated is used to meet the maintenance requirements of SOLAS Regulation IV/15 (incorporated by reference, see Sec. 15.103 of this part), must provide documentary evidence that he or she is competent to maintain GMDSS equipment at sea. [USCG-2004-17914, 78 FR 78008, Dec. 24, 2013]