220 ILCS 5/4-401

If any Section, subdivision, sentence or clause of this Act is for any reason held invalid or to be unconstitutional, such decision shall not affect the validity of the remaining portions of this Act. A substantial compliance with the requirements of this Act shall be sufficient to give effect to all the Acts, orders, decisions, rules and regulations of the Commission and they shall not be declared inoperative, illegal or void for any omission of a technical nature in respect thereto.