42 CFR §21.26

1. (a)Requirements; all candidates. Except as otherwise provided in this section every candidate for examination for appointment in the grade of assistant:
   1. (1)Shall meet the requirements for eligibility for examination for appointment in the grade of junior assistant;
   2. (2)Shall be at least 21 years of age; and
   3. (3)Shall have had at least 7 years of educational and professional training or experience subsequent to high school, except that a candidate who applies for examination for appointment in the Reserve Corps to serve as a medical or dental intern may be examined for such appointment upon the completion of 6 years of such education, training, or experience.
2. (b)Additional requirements; dietitians. Every candidate for examination for appointment as a dietitian shall have successfully completed an approved training course for dietetic interns.