D.C. Code § 32-1407

For the purposes of this subchapter, the term “apprentice” means a worker at least 16 years of age, except when a higher minimum age standard is otherwise fixed by law, who is employed to learn an apprenticeable occupation meeting the criteria approved by the Registration Agency and who has entered into a written apprenticeship agreement, which contains the terms and conditions of the employment and training of the apprentice, with either the apprentice’s program sponsor or an apprenticeship committee acting as agent for the program sponsor.