S.C. Code § 50-21-116
Notwithstanding any other provision of law, a person must submit to either one or a combination of chemical tests of his breath, blood, or urine for the purpose of determining the presence of alcohol, drugs, or a combination of alcohol and drugs, if there is probable cause to believe that the person violated or is under arrest for a violation of Section 50-21-113.
The tests must be administered at the direction of a law enforcement officer who has probable cause to believe that the person violated or is under arrest for violation of Section 50-21-113. The administration of one test does not preclude the administration of other tests. The resistance, obstruction, or opposition to testing pursuant to this section is evidence admissible at the trial of the offense which precipitated the requirement for testing. A person who is tested or gives samples for testing may have a qualified person of his choice conduct additional tests at his expense and must be notified of that right. A person's request or failure to request additional blood or urine tests is not admissible against the person in the criminal trial.
The provisions of Section 50-21-114, relating to the administration of tests to determine a person's alcohol concentration, additional tests at the person's expense, the availability of other evidence on the question of whether or not the person was under the influence of alcohol, drugs, or a combination of them, availability of test information to the person or his attorney, and the liability of medical institutions and person administering the tests are applicable to this section and also extend to the officer requesting the test, the State or its political subdivisions, or governmental agency, or entity which employs the officer making the request, and the agency, institution, or employer, either governmental or private, of persons administering the tests. Notwithstanding any other provision of law pertaining to confidentiality of hospital records or other medical records, information regarding tests performed pursuant to this section must be released, upon subpoena, to a court, prosecuting attorney, defense attorney, or law enforcement officer in connection with an alleged violation of Section 50-21-113.
S.C. Code § 50-21-116