AMBULANCE means any vehicle, whether an air, ground or water vehicle, that is designed, constructed, or routinely used or intended to be used for the transportation of ill or injured persons. The licensing of these vehicles is in addition to any registration required by any other authorities. For the purposes of these Rules, vehicles operated by the Maine Army National Guard, Maine Air National Guard or the United States armed forces are not considered ambulances.
16-163 C.M.R. ch. 2, § 2