This Standard establishes criteria for those items of trim for water-closet bowls, tanks, and urinals known as spuds, locknuts for spuds, flush valves, and flush elbows. Requirements for fill valves (ballcocks) are defined in ANSI/ASSE 1002. This Standard does not address the compatibility of materials. Nothing stated herein shall preclude the production of special design flush valves with unique non-standard features for use in low consumption plumbing fixtures.