8 C.F.R. § 330.1 Eligibility.
To be eligible for naturalization under section 330 of the Act, an applicant must establish that he or she:
(a) Has been lawfully admitted as a permanent resident of the United States;
(b) Has served honorably or with good conduct, during such periods of lawful residence, in a capacity other than as a member of the Armed Forces of the United States, on board:
(1) A vessel operated by the United States, or an agency thereof, the full legal and equitable title to which is in the United States; or
(2) A vessel, whose home port is the United States, and
(i) Which is registered under the laws of the United States; or
(ii) The full legal and equitable title to which is in a citizen of the United States, or a corporation organized under the laws of any of the several States of the United States;
(c) Served in the capacity specified in paragraph (b) of this section within five years immediately preceding the date on which the applicant filed the application for naturalization, or on which the alien is examined, if the application was filed early pursuant to section 334(a) of the Act.
(d) Has been, during the five years preceding the filing of the application for naturalization, or the examination on the application if the application was filed early under section 334(a) of the Act, and continues to be, of good moral character, attached to the principles of the Constitution of the United States, and favorably disposed toward the good order and happiness of the United States.
(1) An applicant is presumed to satisfy the requirements of this paragraph during periods of service in accordance with paragraphs (b) and (c) of this section, as reflected by the records and certificates submitted by the applicant under § 330.2(b).
(2) An applicant must demonstrate that he or she satisfies the requirements of this paragraph for those required periods when that applicant did not perform service in accordance with paragraphs (b) and (c) of this section; and
(e) Has complied with all other requirements for naturalization as provided in part 316 of this chapter, except that, for purposes of the residence requirements under paragraphs § 316.2 (a)(3) and (a)(4) of this chapter, service satisfying the conditions of this section shall be considered as residence and physical presence within the United States.