Ohio Rev. Code § 5715.02
The county treasurer, county auditor, and a member of the board of county commissioners selected by the board of county commissioners shall constitute the county board of revision, or they may provide for one or more hearing boards when they deem the creation of such to be necessary to the expeditious hearing of valuation complaints. Each such official may appoint one qualified employee from the official's office to serve in the official's place and stead on each such board for the purpose of hearing complaints as to the value of real property only, each such hearing board has the same authority to hear and decide complaints and sign the journal as the board of revision, and shall proceed in the manner provided for the board of revision by sections 5715.08 to 5715.20 of the Revised Code. Any decision by a hearing board shall be the decision of the board of revision.
A majority of a county board of revision or hearing board shall constitute a quorum to hear and determine any complaint, and any vacancy shall not impair the right of the remaining members of such board, whether elected officials or appointees, to exercise all the powers thereof so long as a majority remains.
Each member of a county board of revision or hearing board may administer oaths.
R.C. § 5715.02