UNI-BELL PVC PIPE ASSOCIATION UNI-B-9-90 RECOMMENDED PERFORMANCE SPECIFICATION FOR POLYVINYL CHLORIDE (PVC) PROFILE WALL GRAVITY SEWER PIPE AND FITTINGS BASED ON CONTROLLED INSIDE DIAMETER (NOMINAL PIPE SIZES 4 - 48 INCH) July 1990 UNI-BELL PVC PIPE ASSOCIATION 2711 LBJ Freeway, Suite 1000 Dallas, TX 75234 Phone: 972.243.3902 Fax: 972.243.3907 www.uni-bell.org