No business shall be transacted by the commission without the presence of a quorum of four (4) commissioners. The commission shall meet regularly at least once each calendar quarter. A special meeting of the commission may be called by the chairperson, by any four (4) commissioners, or by the board of trustees. Notice shall be given to all commissioners in compliance with the Illinois open meetings act prior to any special meeting. All meetings shall be open to the public except when closed pursuant to the provisions of the open meetings act. (Ord. O2015-32, 10-7-2015; amd. Ord. O2019-31, 10-1-2019)