The emergency services organization shall:
(a) Cooperate fully with the emergency services functions of the State and the County;
(b) Provide for the rendering of mutual aid with reference to other cities and counties within the State and if necessary and only with specific approval of the Director, subject to the approval of the Mayor and the Governor of the State, the neighboring counties and cities of another state; and
(c) While cooperating with other agencies as provided in subsections (a) and (b) hereof, remain insofar as practicable a self-sustaining and independent unit. (1970 Code Sec. 7-4)