1.1 This specification covers performance requirements, test methods, and marking requirements for metric-sized system components (electrofusion and mechanical fittings) when joined with metric-sized PEX pipe (Specification F2788) as a system, intended for use up to and including a maximum working temperature of 200°F (93°C ). The following performance requirements are described for the fittings – 68°F (20°C) hydrostatic strength, 176°F (80°C) hydrostatic strength, short-term internal pressure resistance, resistance to tensile loads, cohesive resistance for electrofusion fittings at both the minimum and maximum recommended temperatures, impact resistance for saddle fittings, and leak tightness and pull out tests for mechanical fittings. The metric-sized components covered by this specification are intended for the above-ground and buried pressure piping applications, such as industrial & general-purpose pipelines, potable water pipelines, and fire – extinguishing pipelines.

1.2 The text of this specification references notes, footnotes, and appendixes, which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the specification.

1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3.1 Exception—Except for dimensions, the values stated in inch-pound units are to be regarded as standard. The values given in parentheses for nominal sizes are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.

Note 1—Metric sized (SI units) pipe (Specification F2788) should only be joined with corresponding metric sized fittings (such as Specification F2788, ISO 4427-3 or ISO 15875-3). Inch sized fittings should not be used for metric-sized pipe.

Note 2—Suggested hydrostatic design stresses and hydrostatic pressure ratings for pipe and fittings are listed in Appendix X1. Design, assembly, and installation considerations are discussed in Appendix X2. An optional performance qualification and an in-plant quality control program are recommended in Appendix X3.

1.4 The following safety hazards caveat pertains only to the test method portion, Section 7, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.