46 CFR § 11.805 - General requirements.
(a) The applicant for an endorsement as staff officer is not required to take any examination; however, the applicant must present to the Coast Guard a letter justifying the need for the endorsement.
(b) An applicant for a higher grade in the staff department must apply in the same manner as for an original endorsement and must surrender the previous Coast Guard-issued credentials upon issuance of the new MMC. A staff officer may serve in a lower grade of service for which he or she is registered.
(c) Title 46 U.S.C. 8302 addresses uniforms for staff officers who are members of the Naval Reserve.
(d) A duplicate MMC may be issued by the Coast Guard. (See § 10.229 of this subchapter.)
(e) An MMC is valid for a term of 5 years from the date of issuance. Procedures for renewing endorsements are found in § 10.227 of this subchapter.
(f) Each applicant for an original or a higher grade of endorsement, as described in paragraph (b) of this section, must produce evidence of having passed a chemical test for dangerous drugs or of qualifying for an exception from testing in § 16.220 of this subchapter. An applicant who fails a chemical test for dangerous drugs will not be issued an MMC.