20 ILCS 3960/12.4

If a hospital reduces any of the Categories of Service as outlined in Title 77, Chapter II, Part 1110 in the Illinois Administrative Code, or any other service as defined by rule by the State Board, by 50% or more according to rules adopted by the State Board, then within 30 days after reducing the service, the hospital must give written notice of the reduction in service to the State Board, the Department of Public Health, and the State Senator and State Representative serving the legislative district in which the hospital is located. The State Board shall adopt rules to implement this Section, including rules that specify (i) how each health care service is defined, if not already defined in the State Board's rules, and (ii) what constitutes a reduction in service of 50% or more.