77 Ill. Adm. Code 890.1120
Color Code
Section 890
Section 890.1120Â Color Code
Identification of Piping. All
piping conveying non-potable water shall be permanently identified by a continuous
purple coloring so that the piping is readily distinguishable from piping
carrying potable water. (See the color codes of ANSI/NEMA Z535.1 and ASME
A13.1.)