§ 1345-1.4.7. Vacancies in the classified service are to be filled by promotion whenever practicable, except that whenever three (3) or less eligible employees file applications for a promotional examination, or whenever three (3) or less employees in a department are eligible for a promotion to a position in that department, the appointing authority may, upon written justification and approval of the Personnel Director, nominate an employee for promotion, or the appointing authority, in his discretion, may call for a departmental, county service-wide or open examination. In the event of a disapproval as to any nomination, the appointing authority may appeal directly to the Commission.