(a) The following medical transportation providers are exempt from the assessment imposed under § 20-77-2803 unless the exemption is adjudged to be unconstitutional or otherwise determined to be invalid:
(1) Volunteer ambulance services;
(2) Ambulance services owned by the state, county, or political subdivision;
(3) Nonemergency ambulance services;
(4) Air ambulance services; and
(5) Specialty-hospital-based ambulance services.
(b) If an exemption under subsection (a) of this section is adjudged to be unconstitutional or otherwise determined to be invalid, the applicable medical transportation provider shall pay the assessment imposed under § 20-77-2803.