ISO 4427-2:2019

Plastics piping systems for water supply, and for drainage and sewerage under pressure - Polyethylene (PE) - Part 2: Pipes

This document specifies the pipes made from polyethylene (PE) for buried or above ground applications, intended for the conveyance of: - water for human consumption; - raw water prior to treatment; - drainage and sewerage under pressure; - vacuum sewer systems; - water for other purposes. NOTE 1 The intended uses include sea outfalls, laid in water and pipes suspended below bridges. Pipes complying with this document are not intended for the transport of water intended for human consumption in contaminated soils unless special consideration has been taken. NOTE 2 For example, ISO 21004 provides an alternative solution for use in contaminated soils. See Reference [3] in the Bibliography. This document specifies three types of pipe: - PE pipes (outside diameter dn), including any identification stripes; - PE pipes with co-extruded layers on either or both the outside and/or inside of the pipe (total outside diameter dn) where all layers have the same MRS rating; - PE pipes (outside diameter dn) having a peelable and contiguous thermoplastics additional layer on the outside of the pipe ("coated pipe"). This document also specifies the test parameters for the test methods referred to in this document. In conjunction with the other parts of the ISO 4427 series, this document is applicable to PE pipes, their joints and to joints with components made of PE and other materials, intended to be used under the following conditions: a) a maximum allowable operating pressure (PFA) up to and including 25 bar[1]; b) an operating temperature of 20 °C as the reference temperature. NOTE 3 For other operating temperatures, guidance is given in ISO 4427‑1:2019, Annex A. This document covers a range of maximum allowable operating pressures and gives requirements concerning colours. NOTE 4 It is the responsibility of the purchaser or specifier to make the appropriate selections from these aspects, taking into account their particular requirements and installation practices or codes. [1] 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.

Systèmes de canalisations en plastique destinés à l'alimentation en eau et aux branchements et collecteurs d'assainissement sous pression — Polyéthylène (PE) — Partie 2: Tubes

General Information

• Status: Published
• Publication Date: 05-Aug-2019
• ICS: 23.040.20 - Plastics pipes
• ICS: 91.140.60 - Water supply systems
• ICS: 93.025 - External water conveyance systems
• Technical Committee: ISO/TC 138/SC 2 - Plastics pipes and fittings for water supplies
• Drafting Committee: ISO/TC 138/SC 2/WG 4 - PE piping systems for water supply
• Current Stage: 9092 - International Standard to be revised
• Start Date: 15-Dec-2025
• Completion Date: 27-Dec-2025

Relations

• Amended By: ISO 4427-2:2019/Amd 1:2023 - Plastics piping systems for water supply, and for drainage and sewerage under pressure - Polyethylene (PE) - Part 2: Pipes - Amendment 1
• Effective Date: 25-Dec-2021
• Revises: ISO 4427-2:2007/Amd 1:2014 - Plastics piping systems - Polyethylene (PE) pipes and fittings for water supply - Part 2: Pipes - Amendment 1
• Effective Date: 20-Aug-2016
• Revises: ISO 4427-2:2007 - Plastics piping systems - Polyethylene (PE) pipes and fittings for water supply - Part 2: Pipes
• Effective Date: 20-Aug-2016

Overview

ISO 4427-2:2019 is the International Standard that specifies requirements for polyethylene (PE) pipes used in water supply and pressure drainage/sewerage systems. It applies to buried or above-ground PE pipes intended for conveying:

• Water for human consumption
• Raw water prior to treatment
• Drainage and sewerage under pressure, including vacuum sewer systems
• Water for other purposes (including sea outfalls, pipes laid in water or suspended under bridges)

The standard covers three pipe types: plain PE pipes, co‑extruded layered PE pipes (all layers having the same MRS rating), and peelable-coated PE pipes. It is part of the ISO 4427 series and is used together with ISO 4427‑1 and other parts.

Key topics and technical requirements

• Scope and use conditions: Designed for maximum allowable operating pressure (PFA) up to and including 25 bar, with a reference temperature of 20 °C. Guidance for other temperatures is in ISO 4427‑1.
• Materials: Pipes shall be made from virgin PE or the manufacturer’s own reprocessed material from the same compound; external recycled materials are not permitted. Identification compounds and co-extrusion materials must be PE-based and fusion-compatible.
• Geometrical & mechanical characteristics: Specifications for outside diameter, wall thickness tolerances, ovality, coiled pipe lengths, conditioning and mechanical testing (including resistance to internal pressure).
• Physical & chemical properties: Tests and limits for effects on water quality, resistance to chemicals (see referenced ISO chemical test methods), oxidation induction time and other physical tests.
• Colours and marking: Colour coding (e.g., blue for potable water; black or black with brown stripes for drainage/sewerage) and minimum marking requirements are defined.
• Testing and annexes: Includes test parameters, plus annexes for co-extruded and peelable-layer pipes and a relationship between PN, MRS, S and SDR.

Practical applications

ISO 4427-2:2019 is used to specify and verify PE piping systems for municipal and industrial water distribution, pressure sewer mains, vacuum sewer systems, sea outfalls and other pressurized water conveyance installations. It ensures consistent performance, compatibility of materials, and traceability of products.

Who uses this standard

• PE pipe manufacturers and compound producers
• Design and civil/utility engineers specifying water and sewer systems
• Procurement officers and infrastructure owners (utilities, municipalities)
• Inspection, testing and conformity-assessment bodies
• Contractors and installers

Related standards

• ISO 4427-1:2019 (General requirements for PE pipes and fittings)
• ISO 21004 (alternative solutions for contaminated soils)
• Other referenced ISO test standards (e.g., ISO 1167, ISO 4433 series)

Keywords: ISO 4427-2:2019, polyethylene pipes, PE pipes, water supply, drainage and sewerage under pressure, PE piping standard, potable water piping.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 4427-2
Second edition
2019-08
Plastics piping systems for water
supply, and for drainage and sewerage
under pressure — Polyethylene (PE) —
Part 2:
Pipes
Systèmes de canalisations en plastique destinés à l'alimentation
en eau et aux branchements et collecteurs d'assainissement sous
pression — Polyéthylène (PE) —
Partie 2: Tubes
Reference number
©
ISO 2019
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Symbols and abbreviated terms . 3
5 Material . 3
5.1 Compound . 3
5.2 Identification compound . 3
5.3 Reprocessed and recycled material . 3
6 General characteristics . 3
6.1 Appearance . 3
6.2 Colour . 3
6.3 Effect on water quality . 4
7 Geometrical characteristics . 4
7.1 Measurements . 4
7.2 Mean outside diameter and out-of-roundness (ovality) . 4
7.3 Wall thicknesses and their tolerances . 6
7.4 Coiled pipe .10
7.5 Lengths .10
8 Mechanical characteristics .10
8.1 Conditioning .10
8.2 Requirements .10
8.3 Retest in case of failure at 80 °C .12
9 Physical characteristics .12
9.1 Conditioning .12
9.2 Requirements .12
10 Chemical characteristics of pipes in contact with chemicals .13
11 Performance requirements .13
12 Marking .14
12.1 General .14
12.2 Minimum required marking of pipes .14
Annex A (normative) Pipes with co-extruded layers .15
Annex B (normative) Pipes with peelable layer .17
Annex C (informative) Relationship between PN, MRS, S and SDR .19
Bibliography .20
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 138, Plastics pipes, fitting and valves for
the transport of fluids, Subcommittee SC 2, Plastics pipes and fittings for water supplies.
This second edition cancels and replaces the first edition (ISO 4427-2:2007), which has been technically
revised. It also incorporates Amendment ISO 4427-2:2007/Amd. 1:2014.
The main changes compared to the previous edition are:
— Update of the normative references;
— Technical consistency with ISO 4437-2 (see Bibliography [1]).
A list of all parts in the ISO 4427 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved

Introduction
The ISO 4427 series of standards are a set of system standards that specify the requirements for a
piping system and its components when made from polyethylene (PE). The piping system is intended
to be used in buried or above ground applications, for the conveyance of water for human consumption,
raw water prior to treatment, drainage and sewerage under pressure, vacuum sewer systems, and
water for other purposes.
In respect of potential adverse effects on the quality of water intended for human consumption caused
by the products covered by the ISO 4427 series, it does not provide information on the restriction on
the use of products.
NOTE Guidance for assessment of conformity can be found in Reference [2] in the Bibliography.
INTERNATIONAL STANDARD ISO 4427-2:2019(E)
Plastics piping systems for water supply, and for drainage
and sewerage under pressure — Polyethylene (PE) —
Part 2:
Pipes
1 Scope
This document specifies the pipes made from polyethylene (PE) for buried or above ground applications,
intended for the conveyance of:
— water for human consumption;
— raw water prior to treatment;
— drainage and sewerage under pressure;
— vacuum sewer systems;
— water for other purposes.
NOTE 1 The intended uses include sea outfalls, laid in water and pipes suspended below bridges.
Pipes complying with this document are not intended for the transport of water intended for human
consumption in contaminated soils unless special consideration has been taken.
NOTE 2 For example, ISO 21004 provides an alternative solution for use in contaminated soils. See
Reference [3] in the Bibliography.
This document specifies three types of pipe:
— PE pipes (outside diameter d ), including any identification stripes;
n
— PE pipes with co-extruded layers on either or both the outside and/or inside of the pipe (total outside
diameter d ) where all layers have the same MRS rating;
n
— PE pipes (outside diameter d ) having a peelable and contiguous thermoplastics additional layer on
n
the outside of the pipe (“coated pipe”).
This document also specifies the test parameters for the test methods referred to in this document.
In conjunction with the other parts of the ISO 4427 series, this document is applicable to PE pipes, their
joints and to joints with components made of PE and other materials, intended to be used under the
following conditions:
1)
a) a maximum allowable operating pressure (PFA) up to and including 25 bar ;
b) an operating temperature of 20 °C as the reference temperature.
NOTE 3 For other operating temperatures, guidance is given in ISO 4427-1:2019, Annex A.
5 2
1) 1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .
This document covers a range of maximum allowable operating pressures and gives requirements
concerning colours.
NOTE 4 It is the responsibility of the purchaser or specifier to make the appropriate selections from these
aspects, taking into account their particular requirements and installation practices or codes.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1133-1, Plastics — Determination of the melt mass-flow rate (MFR) and melt volume-flow rate (MVR)
of thermoplastics — Part 1: Standard method
ISO 1167-1:2006, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination
of the resistance to internal pressure — Part 1: General method
ISO 1167-2, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of
the resistance to internal pressure — Part 2: Preparation of pipe test pieces
ISO 2505, Thermoplastics pipes — Longitudinal reversion — Test method and parameters
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 4427-1:2019, Plastics piping systems — Polyethylene (PE) pipes and fittings for water supply —
Part 1: General
ISO 4427-5:2019, Plastics piping systems — Polyethylene (PE) pipes and fittings for water supply — Part 5:
Fitness for purpose of the system
ISO 4433-1, Thermoplastics pipes — Resistance to liquid chemicals — Classification — Part 1: Immersion
test method
ISO 4433-2, Thermoplastics pipes — Resistance to liquid chemicals — Classification — Part 2: Polyolefin pipes
ISO 6259-1, Thermoplastics pipes — Determination of tensile properties — Part 1: General test method
ISO 6259-3, Thermoplastics pipes — Determination of tensile properties — Part 3: Polyolefin pipes
ISO 11357-6, Plastics — Differential scanning calorimetry (DSC) — Part 6: Determination of oxidation
induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4427-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at http: //www .iso .org/obp
3.1
application code
code letter which identifies the intended use of the product
Note 1 to entry: The code letter mentioned in this document is W indicating "water intended for human
consumption".
2 © ISO 2019 – All rights reserved

4 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviated terms given in ISO 4427-1 apply.
5 Material
5.1 Compound
The pipes shall be made from virgin material or own reprocessed material from the same PE compound
or a mixture of both materials.
Own reprocessed material from the base pipe of peelable-layer pipes can be used. Reprocessed (both
own and external) material from peelable layers shall not be used.
The compound(s) from which the pipes are made shall conform to ISO 4427-1.
NOTE Since PE 40 is not commonly used for pressure applications, it is the intention of ISO/TC 138/SC 2 to
withdraw all references to this compound at the next revision of the ISO 4427 series (all parts).
5.2 Identification compound
The compound used for identification stripes and co-extruded layers (see 6.2) shall be manufactured
from a PE base polymer, which is the same as for one of the material producer’s pipe compounds for
which fusion compatibility has been proven
The compound used for identification stripes shall comply with the fusion compatibility requirements
in ISO 4427-1 and with the resistance to weathering as described in ISO 4427-1:2019, Table 2.
The resistance to weathering of the identification stripe compound shall be declared by the
manufacturer of the compound, confirming whether either a cumulative radiant exposure of >3,5 GJ/
2 2
m or >7 GJ/m related to the outdoor storage ability limit is applicable.
For co-extruded layers used for identification purposes, Annex A applies.
5.3 Reprocessed and recycled material
Clean, reprocessed material generated from a manufacturer's own production and works testing of
products according to the ISO 4427 series may be used if it is derived from the same compound as used
for the relevant production.
Reprocessed material obtained from external sources and recycled material shall not be used.
6 General characteristics
6.1 Appearance
When viewed without magnification, the internal and external surfaces of pipes shall be smooth and
clean and shall have no scoring, cavities and other surface defects to an extent that would prevent
conformity of the pipe to this document.
The pipe ends shall be cut cleanly and square to the axis of the pipe.
6.2 Colour
Blue pipes or black pipes with blue stripes are intended for the conveyance of water for human
consumption only.
The outer coextruded layer of coextruded pipes (see Annex A) or the peelable layer of peelable layer
pipes (see Annex B) for pipes intended for the conveyance of water for human consumption shall be
either black or blue or black with blue stripes.
Pipes intended for drainage and sewerage under pressure shall be black or black with brown stripes or
according to national preference.
For above-ground installations, all components with colours other than black should be protected from
direct UV light.
NOTE Yellow and orange colours are only used for gas applications, in accordance with the ISO 4437 series
(all parts).
6.3 Effect on water quality
For pipes to be used in contact with water intended for human consumption, see ISO 4427-1.
7 Geometrical characteristics
7.1 Measurements
The dimensions of the pipe shall be measured in accordance with ISO 3126. In case of dispute, the
measurements of dimensions shall be made not less than 24 h after manufacture and after conditioning
for at least 4 h at (23 ± 2) °C.
Indirect measurement at the stage of production is allowed at shorter time periods, provided that
evidence is shown of correlation.
7.2 Mean outside diameter and out-of-roundness (ovality)
The mean outside diameters, d and the out-of-roundness (ovality) shall conform to Table 1. For coiled
em,
pipes, the maximum out-of-roundness shall be specified by agreement between the manufacturer and
the end-user.
Pipe from PE 40 materials shall be limited to diameters up to and including 63 mm.
Table 1 — Mean outside diameters and out-of-roundness
Dimensions in millimetres
Nominal outside
Maximum
a
Mean outside diameter
Nominal size
diameter
out-of-roundness
DN/OD
b
(ovality)
d d d
n em min em max
16 16 16,0 16,3 1,2
20 20 20,0 20,3 1,2
25 25 25,0 25,3 1,2
32 32 32,0 32,3 1,3
40 40 40,0 40,4 1,4
50 50 50,0 50,4 1,4
63 63 63,0 63,4 1,5
a
In accordance with ISO 11922-1:2018 , grade B, for sizes ≤630 and grade A for sizes ≥710. (See Reference [4] in the
Bibliography).
b
In accordance with ISO 11922-1:2018 , grade N, for sizes ≤800, to be measured at the point of manufacture.
c
Tolerance calculated as 0,009 d and does not conform to grade A in ISO 11922-1:2018 .
em
d
For straight pipes with diameters ≥900, the maximum out-of-roundness shall be specified by an agreement between
the manufacturer and the end-user.
4 © ISO 2019 – All rights reserved

Table 1 (continued)
Nominal outside
Maximum
a
Mean outside diameter
Nominal size
diameter
out-of-roundness
DN/OD
b
(ovality)
d d d
n em min em max
75 75 75,0 75,5 1,6
90 90 90,0 90,6 1,8
110 110 110,0 110,7 2,2
125 125 125,0 125,8 2,5
140 140 140,0 140,9 2,8
160 160 160,0 161,0 3,2
180 180 180,0 181,1 3,6
200 200 200,0 201,2 4,0
225 225 225,0 226,4 4,5
250 250 250,0 251,5 5,0
280 280 280,0 281,7 9,8
315 315 315,0 316,9 11,1
355 355 355,0 357,2 12,5
400 400 400,0 402,4 14,0
450 450 450,0 452,7 15,6
500 500 500,0 503,0 17,5
560 560 560,0 563,4 19,6
630 630 630,0 633,8 22,1
710 710 710,0 716,4 24,9
800 800 800,0 807,2 28,0
d
900 900 900,0 908,1 —
d
1 000 1 000 1 000,0 1 009,0 —
c d
1 200 1 200 1 200,0 1 210,8 —
c d
1 400 1 400 1 400,0 1 412,6 —
c d
1 600 1 600 1 600,0 1 614,4 —
c d
1 800 1 800 1 800,0 1 816,2 —
c d
2 000 2 000 2 000,0 2 018,0 —
c d
2 250 2 250 2 250,0 2 270,3 —
c d
2 500 2 500 2 500,0 2 522,5 —
d
2 800 2 800 2 800,0 2 825,2c —
c d
3 000 3 000 3 000,0 3 027,0 —
a
In accordance with ISO 11922-1:2018 , grade B, for sizes ≤630 and grade A for sizes ≥710. (See Reference [4] in the
Bibliography).
b
In accordance with ISO 11922-1:2018 , grade N, for sizes ≤800, to be measured at the point of manufacture.
c
Tolerance calculated as 0,009 d and does not conform to grade A in ISO 11922-1:2018 .
em
d
For straight pipes with diameters ≥900, the maximum out-of-roundness shall be specified by an agreement between
the manufacturer and the end-user.
NOTE Tolerance bands in accordance with ISO 11922-1:2018 , are calculated as follows, as applicable (see
Reference [3] in the Bibliography):
a) Grade A: 0,009d rounded to the next greater 0,1 mm with a minimum value of 0,3 mm and a maximum value
n
of 10,0 mm.
b) Grade B: 0,006d rounded up to the next greater 0,1 mm with a minimum value of 0,3 mm and a maximum
n
value of 4,0 mm.
c) Grade N:
1)  for diameters ≤75 mm     (0,008 d + 1) mm,
n
2)  for diameters ≥90 mm and ≤250 mm (0,02 d ) mm,
n
3)  for diameters >250 mm     (0,035 d ) mm,
n
4)  rounded up to the next greater 0,1 mm.
7.3 Wall thicknesses and their tolerances
The wall thickness shall be in accordance with Table 2.
NOTE The relationship between PN, MRS, S and SDR is given in Annex C.
6 © ISO 2019 – All rights reserved

Table 2 — Wall thicknesses
Pipe series
SDR 6 SDR 7,4 SDR 9 SDR 11 SDR 13,6 SDR 17 SDR 21 SDR 26 SDR 33 SDR 41
S 2,5 S 3,2 S 4 S 5 S 6,3 S 8 S 10 S 12,5 S 16 S 20
Nominal pressure (PN)
bar
PE 40 — PN 10 PN 8 PN 6 PN 5 PN 4 PN 3,2 PN 2,5 — —
PE 80 PN 25 PN 20 PN 16 PN 12,5 PN 10 PN 8 PN 6 PN 5 PN 4 PN 3,2
PE 100 — PN 25 PN 20 PN 16 PN 12,5 PN 10 PN 8 PN 6 PN 5 PN 4
b
Wall thicknesses
Nomi-
mm
nal
size
e e e e e e e e e e e e e e e e e e e e
min max min max min max min max min max min max min max min max min max min max
a a
16 3,0 3,4 2,3 2,7 2,0 2,3 — — — — — — — — — — — — — —
a a
20 3,4 3,9 3,0 3,4 2,3 2,7 2,0 2,3 — — — — — — — — — — — —
a a
25 4,2 4,8 3,5 4,0 3,0 3,4 2,3 2,7 2,0 2,3 — — — — — — — — — —
a a
32 5,4 6,1 4,4 5,0 3,6 4,1 3,0 3,4 2,4 2,8 2,0 2,3 — — — — — — — —
a a
40 6,7 7,5 5,5 6,2 4,5 5,1 3,7 4,2 3,0 3,5 2,4 2,8 2,0 2,3 — — — — — —
a a
50 8,3 9,3 6,9 7,7 5,6 6,3 4,6 5,2 3,7 4,2 3,0 3,4 2,4 2,
...