72 Pa. Stat. § 5341.3
The board shall organize within fifty days after this amending act becomes effective, to select a chairman, vice-chairman, and secretary from among its members; and thereafter, whenever a vacancy shall exist or happen in any of such offices, the board shall thereupon meet and select one of its members to fill such vacancy. Each member of the board hereafter selected as chairman, vice-chairman or secretary, either upon the organization of the board or to fill any vacancy, shall hold such office until the expiration of his term as a member of the board. Each member of the board shall give bond in such amount and with surety or sureties as the tax-levying body of the county shall approve, conditioned for the faithful performance of his duties as a member of the board.
72 P.S. § 5341.3