CFR › Title 22 › Part 305 › §305.222 CFR §305.2Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗Copy linkIn order to be eligible for enrollment as a Volunteer, Applicants must meet mandatory citizenship and age requirements.(a)Citizenship. The Applicant must be a citizen or national of the United States prior to entering on duty as a Trainee.(b)Age. The Applicant must be at least 18 years old at the time of entry on duty as a Trainee.