Overview
EN ISO 11296-4:2018/A1:2021 is Amendment 1 to Part 4 of the ISO 11296 series: Plastics piping systems for renovation of underground non-pressure drainage and sewerage networks - Lining with cured-in-place pipes (CIPP). Published by CEN in 2021, this amendment updates definitions, marking requirements and introduces a procedure for an alternative expression of flexural test results for cured-in-place pipe systems used in non-pressure sewer and drainage renovation.
Key topics and technical requirements
- Updated terms and definitions: New and revised definitions clarify terminology used in CIPP manufacture and installation, such as carrier material, CIPP product, CIPP unit, and nominal CIPP “M” and “I” stage wall thicknesses (symbols e_n,M and e_n,I).
- Marking and thickness requirements: The amendment specifies how manufacturers may mark lining tubes with either nominal “M”‑stage or “I”‑stage wall thickness and how those thicknesses must be measured/documented. It emphasizes deduction of membranes from measured thickness and explains that I‑stage thickness reflects the minimum mean composite thickness after installation.
- Alternative expression of flexural results: Where mean composite thickness or apparent flexural modulus is uncertain (e.g., structured-wall liners, membrane layers, excess resin), flexural characteristics can be expressed as section bending stiffness (EI) and section moment capacity (M) per unit length. Annex B provides the procedure and formula references (e.g., Formulae B.12 and B.13) for deriving EI and M from 3‑point bending tests on flat and curved specimens.
- Normative references updated: The amendment updates referenced test standards to current editions, including ISO 178:2019 (flexural properties), ISO 7685:2019 (initial ring stiffness for GRP), ISO 10467:2018 (GRP systems), ISO 10468, and ISO 14125:1998.
Practical applications and users
This amendment is intended for professionals involved in the specification, manufacture, testing and installation of CIPP systems:
- Manufacturers: to ensure marking, wall‑thickness declarations and quality-plan measurement methods comply with the standard.
- Testing laboratories: to apply the updated flexural test expression (EI, M) and current referenced test methods.
- Design engineers and specifiers: to select appropriate CIPP products and interpret declared M/I stage thicknesses and structural parameters for rehabilitation projects.
- Asset owners / contractors: to verify product conformity, installation claims and performance data for non‑pressure drainage and sewer networks.
Related standards
Keywords: EN ISO 11296-4:2018/A1:2021, CIPP, cured-in-place pipe, lining, non-pressure drainage, sewer renovation, flexural test, marking requirements, plastics piping systems.
