This chapter does not apply to:
(1) a practitioner engaged in the performance of radiological procedures;
(2) a person certified as a medical radiological technologist practicing under Chapter 601;
(3) a person who performs radiological procedures under a practitioner's instruction or supervision;
(4) a person performing beam calibration and characterization, quality assurance, instrument specification, acceptance testing, shielding design, or protection analysis on radiation-emitting equipment or radiopharmaceuticals for procedures not involved with the diagnosis or treatment of a disease or another human medical or dental condition; or
(5) a person who is:
(A) employed by a state or federal regulatory agency; and
(B) performing duties in the scope of the person's employment.