Ill. Admin. Code tit. 26, § 212.294
a) Overtime: For those positions that are not considered executive, administrative or professional as defined under the provisions of 29 CFR 541 and for those executive, administrative or professional positions for which compensatory time is authorized by the Executive Director, authorized work in excess of the scheduled workweek as established by subsection (a)(2) shall be overtime. Overtime may be compensated in cash or compensatory time.
2) The definition of a scheduled workweek is as follows: