Maryland Code, Transportation § 11-118

(1) Vehicles of federal, State, or local law enforcement agencies;

(2) Vehicles of volunteer fire companies, rescue squads, fire departments, the Maryland Institute for Emergency Medical Services Systems, and the Maryland Fire and Rescue Institute;

(3) State vehicles used in response to oil or hazardous materials spills;

(4) State vehicles designated for emergency use by the Commissioner of Correction;

(5) Ambulances;

(6) Organ delivery vehicles; and

(7) Special vehicles funded or provided by federal, State, or local government and used for emergency or rescue purposes in this State.