ISO 22391-5:2009

Overview

ISO 22391-5:2009 defines the fitness for purpose requirements for plastics piping systems made from polyethylene of raised temperature resistance (PE-RT) - both Type I and Type II - intended for hot and cold water installations inside buildings (domestic and heating systems). The standard covers pipes, fittings, joints and mixed-material assemblies under the design pressures and temperatures defined by ISO 22391-1. It specifies the range of service classes, pipe dimension classes, required test parameters and applicable test methods to verify system performance.

Key topics and technical requirements

• Scope and applicability
  • Applies to PE-RT Type I and Type II piping systems for conveying hot and cold water (including systems that may supply drinking water), under the design limits set in ISO 22391-1.
  • Not applicable beyond the maximum design or malfunction temperatures in ISO 22391-1.
• Fitness-for-purpose tests
  • Internal pressure test (based on ISO 1167-1/2): joint assemblies must resist hydrostatic test pressures (test durations typically 1 000 h at defined test temperatures) without leakage.
  • Bending test (EN 713): verifies leaktightness under bending for DN ≥ 32 mm; typical test duration is 1 h at 20 °C.
  • Pull-out test (EN 712): determines resistance of end-load-bearing mechanical joints to longitudinal force; forces are calculated from pipe diameter and design pressure.
  • Thermal cycling test (EN 12293): validates integrity under repeated temperature changes (applies separately to flexible and rigid pipes).
  • Pressure cycling test (EN 12295) and Leaktightness under vacuum test (EN 12294): included for relevant joint types.
• Joint and assembly scope
  • Tests cover socket fusion, electrofusion and mechanical joints, and combinations of PE-RT with other plastics or non-plastic components.
• Reference test standards
  • ISO 1167, EN 712, EN 713, EN 12293, EN 12294, EN 12295.

Applications and who uses it

• Manufacturers of PE-RT pipes, fittings and jointing systems use ISO 22391-5 to demonstrate product fitness for domestic hot/cold water and heating installations.
• Test laboratories and quality assurance teams apply the specified test methods and parameters for certification and compliance testing.
• Specifiers, engineers and consultants reference the standard when selecting piping systems for building services to ensure long-term performance under expected pressures and temperatures.
• Regulators and authorities use the standard to align national requirements and approve products for potable water and heating systems.

Related standards

• ISO 22391-1 (General), ISO 22391-2 (Pipes), ISO 22391-3 (Fittings)
• Other system standards for hot/cold water: ISO 15874 (PP), ISO 15875 (PE-X), ISO 15876 (PB), ISO 15877 (PVC‑C)

Keywords: ISO 22391-5, PE-RT, plastics piping systems, fitness for purpose, internal pressure test, bending test, thermal cycling, pull-out test, hot and cold water installations.