Ill. Admin. Code tit. 35, § 229.170
c) An operator training program shall satisfy all of the following criteria:
1) Consist of at least 24 hours of training covering the following subjects:
e) In order for an operator that has been qualified in accordance with subsection (b) of this Section to maintain the necessary qualification status, the operator shall:
1) Complete and pass an annual review course of at least 4 hours in length that, at a minimum, covers the following subjects: