S.C. Code Regs. § 117-336
A "facility" is generally a single physical location, where a taxpayer's business is conducted or where its services or industrial operations are performed. Where two or more distinct and separate economic activities are performed at a single physical location, each separate economic activity will be treated as a separate facility when: (1) each activity has its own separate and dedicated personnel; (2) separate reports can be prepared on the numbers of employees, their wages and salaries, sales, or receipts and expenses; (3) and employment and output are significant as to the activity. For purposes of item (2) above, it is irrelevant if separate reports are actually prepared, so long as separate reports can be prepared, this criteria is met.
S.C. Code Regs. 117-336