Overview
EN ISO 13479:2022 (ISO 13479:2022) specifies a standardized laboratory method to determine the resistance to slow crack growth of polyolefin pipes used for the conveyance of fluids. The method quantifies crack propagation resistance as time to failure during a hydrostatic pressure test performed on pipes with machined longitudinal notches on the outside surface. The procedure applies to polyolefin pipes with a wall thickness greater than 5 mm. This edition (2022) supersedes earlier editions and has been adopted as a CEN standard (EN ISO 13479:2022).
Key topics and technical requirements
- Test principle: Hydrostatic-pressure testing of notched pipes; results reported as time-to-failure under defined test conditions.
- Test-piece preparation: Detailed requirements for selection, machining and location of longitudinal notches (including notch radius measurement and maximum specified notch radius).
- Ligament measurement: Determination and reporting of remaining ligament thickness after notch machining and after testing.
- Conditioning and procedure: Conditioning of specimens and step-by-step hydrostatic testing instructions to ensure repeatability.
- Annexes:
- Normative and informative annexes covering ligament thicknesses, test-pressure levels for polyethylene, recommended requirements, and a specific accelerated notched pipe test (ANPT) for PE100-RC.
- A normative method for measuring notch radius.
- Revisions in 2022 edition: Added warnings about preparation/procedure influences, specification of a maximum notch radius, alternative test pressure/time options for premature failures (PE 80 and PE 100), and an accelerated method using an external detergent.
Practical applications and users
This standard is intended for:
- Pipe manufacturers and material suppliers for product development, quality control, and demonstrating long-term durability against slow crack growth.
- Third‑party test laboratories performing standardized mechanical testing of polyolefin piping systems.
- Design and project engineers specifying piping materials for water, gas, and industrial fluid conveyance where resistance to crack propagation is critical.
- Certification bodies, regulators, and specifiers requiring harmonized test evidence for compliance and product comparison.
Practical benefits include improved material selection, reliable lifetime performance assessment, and consistent reporting of slow crack growth resistance for polyethylene and other polyolefins.
Related standards
Relevant referenced standards used with EN ISO 13479:2022 include:
Keywords: EN ISO 13479:2022, ISO 13479, polyolefin pipes, slow crack growth, notched pipe test, hydrostatic pressure test, ligament thickness, PE100-RC, ANPT, crack propagation resistance, polyethylene pipe testing.
