425 ILCS 15/6

Any person may at any time make complaint in writing to the authorities whose duty it is hereunder to enforce this law, that such escape or escapes are needed or are unsafe or insufficient, and it shall be the duty of such authorities to inspect such building or buildings, and escape or escapes, and cause notice to be served on the owner or owners, trustees, lessee or occupant, as provided in section three (3) of this Act, and such owner or owners, trustees, lessee or occupant shall immediately take steps to overcome the cause of complaint.