“Authorized emergency vehicle” means vehicles of a fire department, duly chartered rescue squad, police department, ambulance service, hospital police department, state, county, or municipal agency, and such privately owned ambulances, tow trucks, wreckers, flag car services, vehicles providing road service to disabled vehicles, service vehicles of a public service corporation, postal service vehicles, snow removal equipment, Class A vehicles of firefighters, Class A vehicles of members of ambulance services, Class A vehicles of members of duly chartered rescue squads, emergency management and operations vehicles operated by airports and designated pursuant to § 17C-15-26 of this code, and all other emergency vehicles as are designated by the agency responsible for the operation and control of these persons or organizations. Class A vehicles are as defined by § 17A-10-1 of this code. Agency authorization and emergency equipment are provided in § 17C-15-26 of this code. Agencies responsible for issuing authorization for emergency vehicle permits may promulgate such regulations that are necessary for the issuance of permits for emergency vehicles. In the event that emergency medical technicians (“EMTs”) or paramedics on the scene of an emergency are unable to drive an ambulance in the course of administering patient care, firefighters on the scene shall be permitted to drive an ambulance: Provided, That the fire department with which the firefighters are associated or members and the emergency medical services provider that owns the ambulance have previously entered into a memorandum of understanding or other agreement authorizing such action and the firefighter driving the ambulance has completed an Emergency Vehicle Operations Course (“EVOC”) otherwise required by this code or legislative rule promulgated thereunder.