S.C. Code Ann. § 7-13-70
For the purpose of carrying on general or special elections provided for in Section 7-13-10, the Governor, at least ninety days before the election, must appoint for each county not less than three nor more than five commissioners of election upon the recommendation of the senatorial delegation and at least half of the members of the House of Representatives from the respective counties. The Governor must notify the State Election Commission in writing of the appointments. The State Election Commission must verify that at least one of the appointees represents the largest political party and one represents the second largest political party as determined by the composition of that county's delegation in the General Assembly or the makeup of the General Assembly as a whole if the county's delegation is composed of only one party's members. The commissioners shall continue in office until their successors are appointed and qualified. After their appointment the commissioners must take and subscribe, before any officer authorized to administer oaths, the following oath of office prescribed by Section 26 of Article III of the Constitution: "I do solemnly swear (or affirm) that I am duly qualified, according to the Constitution of this State, to exercise the duties of the office to which I have been appointed, and that I will, to the best of my ability, discharge the duties thereof, and preserve, protect and defend the Constitution of this State and of the United States. So help me God".
The oath must be immediately filed in the office of the clerk of court of common pleas of the county in which the commissioners are appointed, or if there is no clerk of court, in the office of the Secretary of State.
Commissioners and such staff as designated by the commission must complete, within eighteen months after their appointment or reappointment, a training and certification program conducted by the State Election Commission. Following initial certification, each commission member and staff person designated by the commission must take at least one training course each year.