S.C. Code Ann. § 58-17-1660

The Office of Regulatory Staff must, when necessary, investigate the books and papers of the railroad companies doing business in this State, ascertain if the rules and regulations of the commission have been complied with, and make personal visitations of railroad offices, stations, and other places of business for the purpose of examination. The Public Service Commission must make rules and regulations concerning the examinations, which rules and regulations must be observed and obeyed as other rules and regulations of the commission.