Ohio Rev. Code § 124.48: Fire department vacancies.

Whenever a vacancy occurs in a promoted rank in a fire department and no eligible list for that rank exists, the appointing authority shall certify the fact to the civil service commission. The civil service commission, within sixty days of the vacancy, shall conduct a competitive promotional examination. After the examination has been held, an eligible list shall be established, and the civil service commission shall certify to the appointing authority the name of the person on the list receiving the highest grade. Upon the certification, the appointing authority shall appoint the person so certified within ten days.

When an eligible list exists and a vacancy occurs in a position for which the list was established, the appointing authority shall certify the fact to the civil service commission. The person standing highest on the list shall be certified to the appointing authority, and that person shall be appointed within ten days.