Each emergency medical services agency for which a license has been issued and emergency medical services vehicle for which a permit has been issued shall be inspected as often as the Commissioner deems necessary and a record thereof shall be maintained. However, no emergency medical services agency or vehicle shall receive additional inspections until every other emergency medical services agency or vehicle in the Commonwealth has been inspected, unless the additional inspections are (i) necessary to follow up on a preoperational inspection or one or more violations, (ii) required by a uniformly applied risk-based schedule established by the Department, (iii) necessary to investigate a complaint regarding the emergency medical services agency or vehicle, or (iv) otherwise deemed necessary by the Commissioner or his designee to protect the health and safety of the public. Each such emergency medical services agency or emergency medical services vehicle, its medical supplies and equipment, and the records of its maintenance and operation shall be available at all reasonable times for inspection.