(a) General rule.--The Pennsylvania State Police may designate any vehicle or group of vehicles as emergency vehicles upon a finding that the designation is necessary to the preservation of life or property or to the execution of emergency governmental functions.
(a.1) Exception.--Vehicles designated as emergency vehicles under this section shall not display or be equipped with a combination of red and blue lights.
(b) Manner and carrying of designation.--The designation shall be in writing and the written designation shall be carried in the vehicle at all times.