S.C. Code § 7-13-110
Each chairman and clerk appointed from among the managers of election for the various polling places must be a resident and registered elector of the respective county in which he is appointed to work or in an adjoining county. All managers of election who are not appointed to serve as chairmen or clerks for the various polling places in the State must be residents and registered electors of the State of South Carolina. Any person qualified to serve as a manager who requests to work in his resident county or an adjoining county must be given priority over qualified persons from other counties for appointment to work in the resident county or an adjoining county. Any person at least sixteen years of age who has completed the training required by Section 7-13-72 and who is not otherwise disqualified by law may be appointed as a poll manager's assistant by the appropriate county board of voter registration and elections. A sixteen- or seventeen-year-old appointed as a poll manager's assistant may not serve as chairman of the managers or clerk in the polling place to which he or she is appointed. Sixteen- and seventeen-year-olds must serve under supervision of the chairman of the managers of the polling place, and their specific duties must be prescribed by the county board of voter registration and elections. One sixteen- or seventeen-year-old assistant poll manager may be appointed for every two regular poll managers appointed to work in a precinct.
S.C. Code § 7-13-110