ISO 4981:2023

Plastics piping systems for non-pressure underground conveyance and storage of non-potable water — Boxes used for retention, detention, storage and transportation systems — Specifications for storm water boxes made of PE, PP and PVC-U

This document gives the definitions and specifies the minimum requirements for injection moulded, extruded, compression moulded and thermoformed thermoplastics cuboid shaped boxes, including integral components, used in underground systems for retention, detention, storage and transportation of non-potable water (e.g. storm water) and manufactured from polyethylene (PE), polypropylene (PP) or unplasticized polyvinylchloride (PVC-U). The boxes are intended for buried underground use, e.g. in landscape, pedestrian or vehicular traffic areas. In the case of retention and detention systems, the main purpose of the boxes is to retain water, for later infiltration in the ground or for later use in non-potable applications (irrigation, cleaning, sanitary facilities, etc.) or to retain water during a storm, transferring it in a controlled way to the public storm water network. Applications include commercial, residential, agricultural and highway drainage, including installation under parking lots and roadways. Product performance is determined by a combination of material specification, product design and manufacturing process. A box can either be factory-assembled or site-assembled from different components. The boxes are intended to be used as elements in a modular system where the manufacturer has provided a clearly documented method specifying how the components are assembled to create a complete retention, detention, storage and transportation system. The boxes are installed as one or more horizontal layers on a firm foundation and embedded with fill around and above the complete system. NOTE Non-load bearing component(s) can be manufactured by various methods (e.g. extrusion, injection moulding, rotational moulding, compression moulded, thermoforming and low-pressure injection moulding) and are not within the scope of this document.

Systèmes de canalisations en plastique pour le transport et le stockage souterrains sans pression de l'eau non potable — Structures alvéolaires ultra-légères utilisées pour les systèmes de rétention, de stockage et de transport — Spécifications relatives aux structures alvéolaires ultra-légères pour eaux pluviales fabriquées à partir de PE, PP et de PVC-U

General Information

• Status: Published
• Publication Date: 26-Jun-2023
• ICS: 23.040.01 - Pipeline components and pipelines in general
• ICS: 93.025 - External water conveyance systems
• Technical Committee: ISO/TC 138/SC 1 - Plastics pipes and fittings for soil, waste and drainage (including land drainage)
• Drafting Committee: ISO/TC 138/SC 1/WG 4 - Plastics piping systems for underground drainage and sewerage
• Current Stage: 6060 - International Standard published
• Start Date: 27-Jun-2023
• Due Date: 29-Apr-2023
• Completion Date: 27-Jun-2023

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 4981
First edition
2023-06
Plastics piping systems for non-
pressure underground conveyance
and storage of non-potable water —
Boxes used for retention, detention,
storage and transportation systems —
Specifications for storm water boxes
made of PE, PP and PVC-U
Systèmes de canalisations en plastique pour le transport et le
stockage souterrains sans pression de l'eau non potable — Structures
alvéolaires ultra-légères utilisées pour les systèmes de rétention, de
stockage et de transport — Spécifications relatives aux structures
alvéolaires ultra-légères pour eaux pluviales fabriquées à partir de
PE, PP et de PVC-U
Reference number
ISO 4981:2023(E)
© ISO 2023

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ISO 4981:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
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]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
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ISO 4981:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviated terms.4
4.1 Symbols . 4
4.2 Abbreviated terms . 4
5 Material. 4
5.1 General . 4
5.2 Polypropylene (PP) material . 5
5.2.1 General . 5
5.2.2 Polypropylene (PP) virgin material . 5
5.2.3 Polypropylene (PP) modified with minerals . 5
5.2.4 Polypropylene (PP) non-virgin material . 5
5.3 Polyethylene (PE) material. 5
5.3.1 General . 5
5.3.2 Polyethylene (PE) virgin material . 5
5.3.3 Polyethylene (PE) modified with minerals . 6
5.3.4 Polyethylene (PE) non-virgin material . . 6
5.4 Unplasticized polyvinylchloride (PVC-U) material . 6
5.4.1 General . 6
5.4.2 Unplasticized polyvinylchloride (PVC-U) virgin material . 6
5.4.3 Unplasticized polyvinylchloride (PVC-U) non-virgin material . 6
5.5 Box and integral components material characteristics . 6
6 General characteristics . 8
6.1 Appearance . 8
6.2 Colour . 8
6.3 Box covered by this document . 8
7 Geometrical characteristics . 8
7.1 Shape . 8
7.2 Dimensions . 9
7.3 Total volume . 9
7.4 Material volume . 9
7.5 Weight . . 9
7.6 Porosity . 9
8 Physical characteristics of boxes .10
8.1 Physical characteristics of injection moulded PP boxes . 10
8.2 Physical characteristics of injection moulded PE boxes . 10
8.3 Physical characteristics of injection moulded PVC-U boxes . 10
9 Mechanical characteristics of boxes including integral components .11
10 Marking . .12
10.1 General .12
10.2 Minimum required marking of boxes .12
Annex A (normative) Characteristics of materials used in boxes and integral components
for PP, PE and PVC-U . .13
Bibliography .16
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ISO 4981:2023(E)
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, fittings and valves for
the transport of fluids, Subcommittee SC 1, Plastics pipes and fittings for soil, waste and drainage (including
land drainage).
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.
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ISO 4981:2023(E)
Introduction
This document specifies systems comprised of boxes made of PE, PP or PVC-U and used for retention,
detention, storage and transportation of storm water.
This document is based on EN 17152-1, additionally including PE materials.
[1]
Guidance for installation can be found in CEN/TR 17179.
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INTERNATIONAL STANDARD ISO 4981:2023(E)
Plastics piping systems for non-pressure underground
conveyance and storage of non-potable water — Boxes
used for retention, detention, storage and transportation
systems — Specifications for storm water boxes made of
PE, PP and PVC-U
1 Scope
This document gives the definitions and specifies the minimum requirements for injection moulded,
extruded, compression moulded and thermoformed thermoplastics cuboid shaped boxes, including
integral components, used in underground systems for retention, detention, storage and transportation
of non-potable water (e.g. storm water) and manufactured from polyethylene (PE), polypropylene (PP)
or unplasticized polyvinylchloride (PVC-U).
The boxes are intended for buried underground use, e.g. in landscape, pedestrian or vehicular traffic
areas.
In the case of retention and detention systems, the main purpose of the boxes is to retain water, for
later infiltration in the ground or for later use in non-potable applications (irrigation, cleaning, sanitary
facilities, etc.) or to retain water during a storm, transferring it in a controlled way to the public storm
water network.
Applications include commercial, residential, agricultural and highway drainage, including installation
under parking lots and roadways.
Product performance is determined by a combination of material specification, product design and
manufacturing process.
A box can either be factory-assembled or site-assembled from different components.
The boxes are intended to be used as elements in a modular system where the manufacturer has
provided a clearly documented method specifying how the components are assembled to create a
complete retention, detention, storage and transportation system. The boxes are installed as one or
more horizontal layers on a firm foundation and embedded with fill around and above the complete
system.
NOTE Non-load bearing component(s) can be manufactured by various methods (e.g. extrusion, injection
moulding, rotational moulding, compression moulded, thermoforming and low-pressure injection moulding) and
are not within the scope of this document.
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 179-1, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test
ISO 306, Plastics — Thermoplastic materials — Determination of Vicat softening temperature (VST)
ISO 472, Plastics — Vocabulary
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
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ISO 4981:2023(E)
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 527-3, Plastics — Determination of tensile properties — Part 3: Test conditions for films and sheets
ISO 580:2005, Plastics piping and ducting systems — Injection-moulded thermoplastics fittings — Methods
for visually assessing the effects of heating
ISO 899-1, Plastics — Determination of creep behaviour — Part 1: Tensile creep
ISO 899-2, Plastics — Determination of creep behaviour — Part 2: Flexural creep by three-point loading
ISO 1043-1:2011, Plastics — Symbols and abbreviated terms — Part 1: Basic polymers and their special
characteristics
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 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion
method, liquid pycnometer method and titration method
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 3451-1, Plastics — Determination of ash — Part 1: General methods
ISO 3451-5, Plastics — Determination of ash — Part 5: Poly(vinyl chloride)
ISO 11357-6, Plastics — Differential scanning calorimetry (DSC) — Part 6: Determination of oxidation
induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT)
ISO 11358-1, Plastics — Thermogravimetry (TG) of polymers — Part 1: General principles
ISO 13229, Thermoplastics piping systems for non-pressure applications — Unplasticized poly(vinyl
chloride) (PVC-U) pipes and fittings — Determination of the viscosity number and K-value
EN 17150, Plastics piping systems for non-pressure underground conveyance and storage of non-potable
water - Test method for determination of short-term compression strength of boxes
EN 17151:2019, Plastics piping systems for non-pressure underground conveyance and storage of non-
potable water - Test method for determination of long-term compression strength of boxes
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 472, ISO 1043-1 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
box
thermoplastic cuboid shaped element, with or without sidewalls, used to create a modular system
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ISO 4981:2023(E)
3.2
integral component
load bearing component contributing to the overall strength of the box
3.3
modular system
system made of repeating boxes
3.4
detention system
modular system designed to attenuate the peak flow from a given site by providing a temporary
underground storm water storage facility
Note 1 to entry: Also known as ‘Attenuation”.
3.5
retention system
modular system designed to provide a temporary underground storage facility from which storm water
infiltrates into the surrounding ground.
Note 1 to entry: Also known as ‘Infiltration”.
3.6
storage system
modular system designed to provide an underground storage facility for storm water
3.7
porosity
total available volume for water storage divided by the total envelope cuboid volume for a box
3.8
long-term compression strength
maximum applied compression stress for which the box will survive without creep rupture for
50 years determined as the lower 95 % confidence limit (LCL) for the stress leading to a failure at the
2
extrapolated lifetime, in kN/m
3.9
virgin material
material in the form such as granules or powder that have not been subjected to use or processing other
than that required for their manufacture and to which no reprocessed or recycled material has been
added
3.10
non-virgin material
material from used or unused retention, detention, storage and transportation boxes which have been
cleaned and crushed or ground, or material from used or unused PE, PP or PVC-U products other than
retention, detention, storage and transportation boxes, regardless of where they are manufactured
3.11
agreed specification
relevant material characteristics agreed between the supplier of the material and the box manufacturer
3.12
type testing
initial testing performed according to the testing requirements in this document, the results of which
are the specified requirements of the specific product being tested
Note 1 to entry: See ISO/IEC 17000:2020, 5.1, for a definition of "specified requirements".
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ISO 4981:2023(E)
4 Symbols and abbreviated terms
4.1 Symbols
For the purposes of this document, the following symbols apply.
e maximum thickness of the component tested
h height, i.e. the vertical distance (in the “z” direction) between the outer surfaces of the
unit
w width, i.e. the smallest horizontal distance (in the “y” direction) between the outer
surfaces of the unit
l length, i.e. the biggest horizontal distance (in the “x” direction) between the outer
surfaces of the unit
P porosity
W weight
V total volume of the unit measured
total
V volume taken by the material
material
V volume not accessible to water or from which water cannot be retrieved
closed
ρ material density (as specified by the material supplier in Table A.2)
4.2 Abbreviated terms
For the purposes of this document, the following abbreviated terms apply.
OIT oxidation induction time
PE polyethylene
PP polypropylene
PVC-U unplasticized polyvinylchloride
IR infrared
P porosity
5 Material
5.1 General
The material shall be either PE, PP or PVC-U, to which may be added:
— mineral modifier(s) of known specification;
— additives needed to facilitate the manufacture of components conforming to this document.
The material used to manufacture the boxes and integral components shall consist of a material or
mixtures of different materials each of which shall have an agreed specification between the supplier
and manufacturer (see Clause A.2).
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ISO 4981:2023(E)
5.2 Polypropylene (PP) material
5.2.1 General
The material shall be either PP virgin, PP modified or PP non-virgin material, conforming to 5.2.2 –
5.2.4 as appropriate.
5.2.2 Polypropylene (PP) virgin material
The material for boxes and integral components shall be a compound of PP virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When reworked material is added to a level of less than 10 %, the material for boxes can still be
considered as virgin.
5.2.3 Polypropylene (PP) modified with minerals
The material for boxes and integral components shall be a compound of PP virgin material modified
with minerals and those additives that are needed to facilitate the manufacture of box or integral
components conforming to the requirements of this document.
If calcium carbonate is used, only coated calcium carbonate shall be used. The content of minerals in
the final compound shall be less than 50 % by mass.
When reworked material is added to a level of less than 10 %, the material for boxes can still be
considered as modified.
5.2.4 Polypropylene (PP) non-virgin material
The material for boxes and integral components shall be a compound of non-virgin PP material and
those additives that are needed to facilitate the manufacture of box or integral components conforming
to the requirements of this document.
Non-virgin materials shall be permitted to be used up to 100 % or added to virgin or reworked material
or a mixture of those two materials.
The content of minerals in the final compound shall be less than 50 % by mass.
5.3 Polyethylene (PE) material
5.3.1 General
The material shall be either PE virgin, PE modified or PE non-virgin material, conforming to 5.3.2 –
5.3.4 as appropriate.
5.3.2 Polyethylene (PE) virgin material
The material for boxes and integral components shall be a compound of PE virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When reworked material is added to a level of less than 10 %, the material for boxes can still be
considered as virgin.
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ISO 4981:2023(E)
5.3.3 Polyethylene (PE) modified with minerals
The material for boxes and integral components shall be a compound of PE virgin material modified
with minerals and those additives that are needed to facilitate the manufacture of box or integral
components conforming to the requirements of this document.
If calcium carbonate is used, only coated calcium carbonate shall be used.
The content of minerals in the final compound shall be less than 50 % by mass.
When reworked material is added to a level of less than 10 %, the material for boxes can still be
considered as modified.
5.3.4 Polyethylene (PE) non-virgin material
The material for boxes and integral components shall be a compound of non-virgin PE material, and
those additives that are needed to facilitate the manufacture of box or integral components conforming
to the requirements of this document.
Non-virgin materials shall be permitted to be used up to 100 % or added to virgin or reworked material
or a mixture of those two materials.
The content of minerals in the final compound shall be less than 50 % by mass.
5.4 Unplasticized polyvinylchloride (PVC-U) material
5.4.1 General
The material shall be either PVC-U virgin or PVC-U non-virgin material, conforming to 5.4.2 and 5.4.3 as
appropriate.
5.4.2 Unplasticized polyvinylchloride (PVC-U) virgin material
The material for boxes or integral components shall be a formulation of PVC-U virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When reworked material is added to a level of less than 10 %, the material can still be considered as
virgin.
5.4.3 Unplasticized polyvinylchloride (PVC-U) non-virgin material
The material for boxes or integral components shall be a formulation of PVC-U non-virgin material
and those additives that are needed to facilitate the manufacture of box and integral components
conforming to the requirements of this document.
Recycled materials from PVC-U products that are available in relevant quantities and intervals of time
shall be permitted to be used up to 100 % by mass or added to virgin or reworked material or a mixture
of those two materials.
5.5 Box and integral components material characteristics
A product in this document is formed by a combination of a material specification, a design and a
manufacturing process. Table 1 specifies the minimum required tests to fingerprint the material and to
specify the material requirements.
In conformance with the results in type testing, a product-specific material specification with specified
requirements shall be defined by the manufacturer.
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ISO 4981:2023(E)
When tested after type testing in accordance with the test methods as specified in Table 1, using the
indicated parameters, the material used for the boxes shall have the characteristics conforming to the
requirements given in Table A.1.
Table 1 — Material characteristics for boxes and integral components
Characteristic Material Requirement Test parameters Test method
Resistance to in- PP End caps: type A (ISO 1167-1:2006) ISO 1167-1 and
ternal pressure Type: water-in-water or water-in-air ISO 1167-2
 Test temperature; 95 °C
(if tensile creep Circumferential stress: 2,5 MPa
The values obtained
rupture is not
PE shall meet or exceed End caps: type A (ISO 1167-1:2006) ISO 1167-1 and
tested)
the specific require- Type: water-in-water or water-in-air ISO 1167-2
ment for the product Test temperature: 80 °C
a
being tested. See Circumferential stress: 2,8 MPa
Annex A.
PVC-U End caps: type A (ISO 1167-1:2006) ISO 1167-1 and
Type: water-in-water or water-in-air ISO 1167-2
Test temperature: 60 °C
Circumferential stress: 6,3 MPa
Tensile creep rup- PP Test stress: 2,5 MPa ISO 899-1
ture
The values obtained
Temperature: 95 °C

shall meet or exceed
PE Test stress: 2,8 MPa ISO 899-1
(if resistance to
the specific require-
internal pressure
ment for the product
Temperature: 80 °C
a
is not tested)
being tested. See
PVC-U Test stress: 6,3 MPa ISO 899-1
Annex A.
Temperature: Vicat −15 °C
Melt mass-flow PP The values obtained Temperature; 230 °C ISO 1133-1
rate shall meet or exceed
Loading mass: 2,16 kg
 the specific require-
PE Temperature: 190 °C ISO 1133-1
Before processing ment for the product
a
being tested. See
Loading mass: 5,0 kg
Annex A.
K-value (only for PVC-U The values obtained ISO 13229 ISO 13229
virgin PVC-U) shall meet or exceed
the specific require-
Vicat softening PVC-U Force: 50 N ISO 306
ment for the product
temperature (VST)
a
Heating rate: 50 K/h
being tested. See
Annex A.
OIT PP The values obtained Temperature: 200 °C ISO 11357-6
shall meet or exceed
PE Temperature: 200 °C ISO 1135
...

DRAFT INTERNATIONAL STANDARD
ISO/DIS 4981
ISO/TC 138/SC 1 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2022-04-25 2022-07-18
Plastic piping systems for non-pressure underground
conveyance and storage of non-potable water — Boxes
used for retention, detention, transportation and storage
systems — Specifications for storm water boxes made of PP
and PVC-U
ICS: 93.025; 23.040.01
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
This document is circulated as received from the committee secretariat.
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 4981:2022(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2022

---------------------- Page: 1 ----------------------
ISO/DIS 4981:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
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]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
  © ISO 2022 – All rights reserved

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ISO/DIS 4981:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols and abbreviations .4
4.1 Symbols . 4
4.2 Abbreviations . 4
5 Material. 4
5.1 General . 4
5.2 Polypropylene (PP) material . 5
5.2.1 General . 5
5.2.2 Polypropylene (PP) virgin material . 5
5.2.3 Polypropylene (PP) modified material . 5
5.2.4 Polypropylene (PP) non-virgin material . 5
5.3 Polyethylene (PE) material. 5
5.3.1 General . 5
5.3.2 Polyethylene (PE) virgin material . 5
5.3.3 Polyethylene (PE) modified material . 6
5.3.4 Polyethylene (PE) non-virgin material . . 6
5.4 Unplasticized polyvinylchloride (PVC-U) material . 6
5.4.1 General . 6
5.4.2 Unplasticized polyvinylchloride (PVC-U) virgin material . 6
5.4.3 Unplasticized polyvinylchloride (PVC-U) non-virgin material . 6
5.5 Box and integral components material characteristics . 6
6 General characteristics . 7
6.1 Appearance . 7
6.2 Colour . 8
6.3 Box covered by this standard . 8
7 Geometrical characteristics . 8
7.1 Shape . 8
7.2 Dimensions . 8
7.3 Total Volume . 8
7.4 Material volume . 8
7.5 Weight . . 9
7.6 Porosity . 9
8 Mechanical characteristics of boxes including integral components .9
9 Physical characteristics of boxes .10
9.1 Physical characteristics of injection moulded PP boxes . 10
9.2 Physical characteristics of injection moulded PE boxes . 10
9.3 Physical characteristics of injection moulded PVC-U boxes . 11
10 Marking . .11
10.1 General . 11
10.2 Minimum required marking of boxes .12
Annex A (normative) Characteristics of materials used in boxes and integral components
for PP, PE and PVC-U . .13
Bibliography .17
iii
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ISO/DIS 4981:2022(E)
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, fittings and valves
for transport of fluids, Subcommittee SC 1, Plastics pipes and fittings for soil, waste and drainage
(including land drainage).
ISO 4981 consists of the following parts under the general title Plastics piping systems for non-pressure
underground conveyance and storage of non-potable water - Boxes used for storage, transportation,
detention and retention systems:
— Part 1: Specifications for storm water boxes made of PP, PE and PVC-U [this document];
— Part 2: Assessment of Conformity [expected].
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.
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ISO/DIS 4981:2022(E)
Introduction
The products covered by this standard are part of storm water management system.
This standard is intended to reflect the current state of knowledge of determining and predicting the
long-term lifetime of product groups mentioned in the scope while maintaining reasonable testing
times for producers and developers of these systems
The International Organization for Standardization (ISO) [and/or] International Electrotechnical
Commission (IEC) draw[s] attention to the fact that it is claimed that compliance with this document
may involve the use of a patent.
ISO [and/or] IEC take[s] no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured ISO [and/or] IEC that he/she is willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the world.
In this respect, the statement of the holder of this patent right is registered with ISO [and/or] IEC.
Information may be obtained from the patent database available at www.iso.org/patents.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those in the patent database. ISO [and/or] IEC shall not be held responsible for
identifying any or all such patent rights.
[1]
Guidance for installation can be found in the CEN/TR 17179:2018
Guidance for design can be found in the CEN/TR 17152-3 (under construction)
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DRAFT INTERNATIONAL STANDARD ISO/DIS 4981:2022(E)
Plastic piping systems for non-pressure underground
conveyance and storage of non-potable water — Boxes
used for retention, detention, transportation and storage
systems — Specifications for storm water boxes made of PP
and PVC-U
1 Scope
This document gives the definitions and specifies the minimum requirements for injection moulded,
extruded, compression moulded and thermoformed thermoplastics cuboid shaped boxes, including
integral components, used in underground systems for storage, transportation, detention and retention
of non-potable water (e.g. storm water) and manufactured from polyethylene (PE), polypropylene (PP)
or unplasticized polyvinylchloride (PVC-U).
These boxes are intended for buried underground use, e.g. in landscape, pedestrian or vehicular traffic
areas.
In the case of detention and retention systems, the main purpose of the boxes is to retain water, for
later infiltration in the ground or for later use in non-potable applications (irrigation, cleaning, sanitary
facilities, etc), or to retain water during a storm, transferring it in a controlled way to the public storm
water network.
Applications include commercial, residential, agricultural, and highway drainage, including installation
under parking lots and roadways.
Product properties are determined by a combination of material specifications, design and
manufacturing process.
A box can either be factory assembled or site assembled from different components.
These boxes are intended to be used as elements in a modular system where the manufacturer has
clearly stated in the documentation how the components are assembled to create a complete storage,
transportation, detention or retention system. They are installed as one or more horizontal layers on a
firm foundation and embedded with fill around and above the complete system.
NOTE 1 Non load bearing component(s) can be manufactured by various methods e.g. extrusion, injection
moulding, rotational moulding, compression moulded, thermoforming and low-pressure injection moulding and
are not part of this standard.
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.
EN 17150, Plastics piping systems for non-pressure underground conveyance and storage of non-potable
water - Test method for determination of short-term compression strength of boxes
EN 17151, Plastics piping systems for non-pressure underground conveyance and storage of non-potable
water - Test method for determination of long-term compression strength of boxes
ISO 179-1, Plastics - Determination of Charpy impact properties - Part 1: Non-instrumented impact test
(ISO 179-1)
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ISO/DIS 4981:2022(E)
ISO 306, Plastics - Thermoplastic materials - Determination of Vicat softening temperature (VST) (ISO 306)
ISO 472:2013, Plastics — Vocabulary
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 527-3, Plastics — Determination of tensile properties — Part 3: Test conditions for films and sheets
ISO 580:2005, Plastics piping and ducting systems — Injection-moulded thermoplastics fittings — Methods
for visually assessing the effects of heating
ISO 899-1, Plastics — Determination of creep behaviour — Part 1: Tensile creep
ISO 899-2, Plastics — Determination of creep behaviour — Part 2: Flexural creep by three-point loading
ISO 1043-1:2011, Plastics — Symbols and abbreviated terms — Part 1: Basic polymers and their special
characteristics
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 1133-1)
ISO 1167-1, 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 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion
method, liquid pycnometer method and titration method
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 3451-1, Plastics — Determination of ash — Part 1: General methods
ISO 3451-5, Plastics — Determination of ash — Part 5: Poly(vinyl chloride)
ISO 11357-6, Plastics — Differential scanning calorimetry (DSC) — Part 6: Determination of oxidation
induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT)
ISO 11358-1, Plastics - Thermogravimetry (TG) of polymers - Part 1: General principles (ISO 11358-1)
ISO 11922-1, Thermoplastics pipes for the conveyance of fluids — Dimensions and tolerances — Part 1:
Metric series
ISO 13229, Thermoplastics piping systems for non-pressure applications — Unplasticized poly(vinyl
chloride) (PVC-U) pipes and fittings — Determination of the viscosity number and K-value
3 Terms and definitions
ln addition to the terms and definitions given below, the terms and definitions given in ISO 472, lSO
1043-1 and ISO 11922-1 apply. ISO and IEC maintain terminological databases for use in standardization
at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
box
thermoplastic cuboid shaped element, with or without sidewalls, used to create a modular system
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ISO/DIS 4981:2022(E)
3.2
integral component
load bearing component contributing to the overall strength of the box
3.3
modular system
system made of repeating boxes
3.4
detention system
modular system designed to attenuate the peak flow from a given site by providing a temporary
underground storm water storage facility
Note 1 to entry: Also known as ‘Attenuation”
3.5
retention system
modular system designed to provide a temporary underground storage facility from which storm water
infiltrates into the surrounding ground
Note 1 to entry: Also known as ‘Infiltration”
3.6
storage system
modular system designed to provide an underground storage facility for storm water
3.7
porosity
total available volume for water storage divided by the total envelope cuboid volume for a box
3.8
long-term compression strength
maximum applied compression stress for which the box will survive without creep rupture for 50
years determined as the lower 95 % confidence limit (LCL) for the stress leading to a failure at the
2
extrapolated lifetime, in kN/m
3.9
material
material specified for a particular component in a box
Note 1 to entry: Boxes consisting of components of different materials are possible.
3.10
virgin material
material in the form such as granules or powder that have not been subjected to use or processing other
than that required for their manufacture and to which no reprocessed or recycled material has been
added
3.11
mineral modified material
material to which minerals have been added during specific processing operation(s) which during such
processing is distributed in the material
3.12
own reprocessed material
material prepared from rejected unused boxes and/or integral components, including trimmings from
the production of boxes, that will be reprocessed in a manufacturer’s plant after having been previously
processed by the same manufacturer by a process such as moulding, extrusion or thermoforming, and
for which the complete formulation is the same
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ISO/DIS 4981:2022(E)
3.13
non-virgin material
material from used or unused storage, transportation, detention and retention boxes which have been
cleaned and crushed or ground, or material from used or unused PE, PP or PVC-U products other than
storage, transportation, detention and retention boxes, regardless of where they are manufactured
3.14
agreed specification
specification of the relevant material characteristics agreed between the supplier of the material and
the box manufacturer
3.15
test duration period
specifies a series of creep rupture tests failing in a specific period of time
3.16
type testing
initial testing performed to prove that the material is capable of conforming to the requirements given
in the relevant standard
4 Symbols and abbreviations
For the purposes of this document, the following symbols and abbreviations apply.
4.1 Symbols
e maximum thickness of the component tested in mm
4.2 Abbreviations
OIT oxidation induction time
PE polyethylene
PP polypropylene
PVC-U unplasticized polyvinylchloride
IR Infrared
P Porosity
TDP test duration period
5 Material
5.1 General
The material shall be one of the following: PE, PP or PVC-U, to which may be added: mineral modifier(s)
of known specification, additives needed to facilitate the manufacture or improve the properties of
components conforming to this document.
The material shall have an agreed specification between supplier and manufacturer or the interested
parties.
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ISO/DIS 4981:2022(E)
5.2 Polypropylene (PP) material
5.2.1 General
The material shall be one of the following: PP virgin, PP modified, or PP non-virgin material, conforming
to clause 5.2.2 – 5.2.4 as appropriate.
5.2.2 Polypropylene (PP) virgin material
The material for boxes and integral components shall be a compound of PP virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When own reprocessed material is added to a level of less than 10 %, the material for boxes can still be
considered as virgin.
5.2.3 Polypropylene (PP) modified material
The material for boxes and integral components shall be a compound of PP virgin material modified
with minerals and those additives that are needed to facilitate the manufacture or improve the
properties of box or integral components conforming to the requirements of this document.
If calcium carbonate is used, only coated calcium carbonate shall be used.
The content of minerals in the final compound shall be less than 50 % by mass.
When own reprocessed material is added to a level of less than 10 %, the material for boxes can still be
considered as modified.
5.2.4 Polypropylene (PP) non-virgin material
The material for boxes and integral components shall be a compound of non-virgin PP material, and
those additives that are needed to facilitate the manufacture or improve the properties of box or
integral components conforming to the requirements of this document.
Non-virgin materials shall be permitted to be used up to 100 % or added to virgin or own reprocessed
material or a mixture of those two materials.
The content of minerals in the final compound shall be less than 50 % by mass.
5.3 Polyethylene (PE) material
5.3.1 General
The material shall be one of the following: PE virgin, PE modified, or PE non-virgin material conforming
to clause 5.3.2 – 5.3.4 as appropriate.
5.3.2 Polyethylene (PE) virgin material
The material for boxes and integral components shall be a compound of PE virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When own reprocessed material is added to a level of less than 10 %, the material for boxes can still be
considered as virgin.
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ISO/DIS 4981:2022(E)
5.3.3 Polyethylene (PE) modified material
The material for boxes and integral components shall be a compound of PE virgin material modified
with minerals and those additives that are needed to facilitate the manufacture or improve the
properties of box or integral components conforming to the requirements of this document.
If calcium carbonate is used, only coated calcium carbonate shall be used.
The content of minerals in the final compound shall be less than 50 % by mass.
When own reprocessed material is added to a level of less than 10 %, the material for boxes can still be
considered as modified.
5.3.4 Polyethylene (PE) non-virgin material
The material for boxes and integral components shall be a compound of non-virgin PE material, and
those additives that are needed to facilitate the manufacture or improve the properties of box or
integral components conforming to the requirements of this document.
Non-virgin materials shall be permitted to be used up to 100 % or added to virgin or own reprocessed
material or a mixture of those two materials.
The content of minerals in the final compound shall be less than 50 % by mass.
5.4 Unplasticized polyvinylchloride (PVC-U) material
5.4.1 General
The material shall be one of the following: PVC-U virgin or PVC-U non-virgin material, conforming to
clause 5.4.2 and 5.4.3 as appropriate.
5.4.2 Unplasticized polyvinylchloride (PVC-U) virgin material
The material for boxes or integral components shall be a formulation of PVC-U virgin material and those
additives that are needed to facilitate the manufacture of box or integral components conforming to the
requirements of this document.
When own reprocessed material is added to a level of less than 10 %, the material can still be considered
as virgin.
5.4.3 Unplasticized polyvinylchloride (PVC-U) non-virgin material
The material for boxes or integral components shall be a formulation of PVC-U non-virgin material
and those additives that are needed to facilitate the manufacture or improve the properties of box and
integral components conforming to the requirements of this document.
Recycled materials from PVC-U products that are available in relevant quantities and intervals of time
shall be permitted to be used up to 100 % by mass or added to virgin or own reprocessed material or a
mixture of those two materials.
5.5 Box and integral components material characteristics
A product in this document is formed by a combination of a material s
...