77 Ill. Adm. Code 890.1940
General Administration
Section 890
Section 890.1940Â General
Administration
The plans and specifications for
a plumbing system whose design does not comply with this Part must be submitted
to the Department for approval prior to installation of such a plumbing
system. Such approval shall be in writing from the Department and shall be
based on a determination that the system is expected to perform and exhibit
durability as if meeting the requirements of this Part.