1.1 This specification covers crosslinked polyethylene(PEX) tubing that incorporates an optional polymeric inner,middle or outer layer and that is outside diameter controlled,made in nominal SDR9 tubing dimension ratios except wherenoted, and pressure rated for water at three temperatures (seeAppendix X1). Included are requirements and test methods formaterial, workmanship, dimensions, burst pressure, hydrostaticsustained pressure, excessive temperature and pressure, envi-ronmental stress cracking, stabilizer functionality, bent-tubehydrostatic pressure, oxidative stability in potable chlorinatedwater, UV resistance, and degree of crosslinking. Require-ments for tubing markings are also given. The componentscovered by this specification are intended for use in, but notlimited to, residential and commercial, hot- and cold-potablewater distribution systems, reclaimed water, fire protection,municipal water service lines, radiant heating and coolingsystems, hydronic distribution systems, snow and ice meltingsystems, geothermal ground loops, district heating, turfconditioning, compressed air distribution and building servicespipe, provided that the PEX tubing covered herein complieswith applicable code requirements.
