ASTM F 3253

This specification covers the requirements, test methods, and markings for crosslinked polyethylene (PEX) tubing with a polymeric oxygen barrier layer, made in one standard dimension ratio (SDR 9), and distribution system components intended for hydronic heating and cooling applications up to and including a maximum working temperature of 200°F (93°C). Components are comprised of tubing, fittings, valves, and manifolds that are intended for use in residential and commercial hydronic heating and cooling systems. Tubing made to this specification incorporates a single outer or middle wall oxygen barrier layer designed to inhibit the transmission or permeation of oxygen through the tubing wall. The requirements and test methods cover materials, workmanship, tubing dimensions and tolerances, burst pressure, sustained pressure, excessive temperature and pressure, thermo-cycling, bent tube, oxidative resistance, layer adhesion, UV resistance, oxygen permeation, and fitting pullout strength tests.

This specification does not apply to potable water applications.