SIST EN ISO 23999:2026

SLOVENSKI STANDARD
oSIST prEN ISO 23999:2025
01-februar-2025
Netekstilne talne obloge - Ugotavljanje dimenzijske stabilnosti in gubanja
(navpična deformacija) po izpostavitvi toploti (ISO/DIS 23999:2024)
Resilient floor coverings - Determination of dimensional stability and curling (vertical
deformation) after exposure to heat (ISO/DIS 23999:2024)
Elastische Bodenbeläge - Bestimmung der Maßhaltigkeit und Schüsselung (vertikale
Verformung) nach Wärmeeinwirkung (ISO/DIS 23999:2024)
Revêtements de sol résilients - Détermination de la stabilité dimensionnelle et de
l'incurvation après exposition à la chaleur (ISO/DIS 23999:2024)
Ta slovenski standard je istoveten z: prEN ISO 23999
ICS:
97.150 Talne obloge Floor coverings
oSIST prEN ISO 23999:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 23999:2025
oSIST prEN ISO 23999:2025
DRAFT
International
Standard
ISO/DIS 23999
ISO/TC 219
Resilient floor coverings —
Secretariat: NBN
Determination of dimensional
Voting begins on:
stability and curling (vertical
2024-12-10
deformation) after exposure to heat
Voting terminates on:
ICS: 97.150
2025-03-04
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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NATIONAL REGULATIONS.
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.
Reference number
ISO/DIS 23999:2024(en)
oSIST prEN ISO 23999:2025
DRAFT
ISO/DIS 23999:2024(en)
International
Standard
ISO/DIS 23999
ISO/TC 219
Resilient floor coverings —
Secretariat: NBN
Determination of dimensional
Voting begins on:
stability and curling (vertical
deformation) after exposure to heat
Voting terminates on:
ICS: 97.150
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2024
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
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WHICH REFERENCE MAY BE MADE IN
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NATIONAL REGULATIONS.
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TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
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RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 23999:2024(en)
ii
oSIST prEN ISO 23999:2025
ISO/DIS 23999:2024(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
4.1 General .2
4.2 Dimensional stability .2
4.3 Curling (vertical deformation) .2
5 Apparatus . 2
5.1 Oven.2
5.2 Support plates .2
6 Measuring devices . 3
6.1 Measurement devices for determination of curling (vertical deformation) .3
6.2 Measurement devices for determination of linear dimension changes .3
6.2.1 Scoring device .3
6.2.2 Rigid steel plate .3
6.2.3 Block and dial gauge apparatus (for tiles and planks) .3
7 Test specimens . 7
7.1 Specimen preparation from sheet or roll material .7
7.2 Specimen preparation from tiles and planks .9
8 Conditioning . 9
9 Test procedure .10
9.1 Initial measurement .10
9.1.1 Curling (vertical deformation) .10
9.1.2 Linear dimensions . . .11
9.2 Heat exposure.11
9.3 Reconditioning. 12
9.4 Final measurement . 12
9.4.1 Curling (vertical deformation) . 12
9.4.2 Linear dimensions . . . 12
10 Calculation and expression of results .12
10.1 Curling (vertical deformation) . 12
10.2 Dimensional change . 13
11 Test report .13
Annex A (informative) Measurement of dimensional change due to heat . 14
Annex B (informative) Calculation and expression of results .15
Bibliography .18

iii
oSIST prEN ISO 23999:2025
ISO/DIS 23999:2024(en)
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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 219, Floor coverings.
This fourth edition cancels and replaces the third edition (ISO 23999:2021), which has been technically
revised.
The main changes are as follows:
— Scope: Minor changes to the wording (for example “determining dimensional stability and curling”
replaced by “dimensional stability and curling (vertical deformation)”)
— Terms and definitions: Adaption/changes to the wording of some definitions and adding missing (e.g.
“machine direction” and “across machine direction”)
— Apparatus: Clearer, more unambiguous deviation between devices used for sheet and/or roll materials
and rectangular shaped elements (squared tiles or long panels), explanation of the use of the so called
“block and dial gauge apparatus” and minor changes/adaptions and correction to the figures (Note: No
device and no figure is completely deleted.)
— Test specimen: Description of the preparation distinguishing sheet and/or roll materials and rectangular
shaped elements (squared tiles or long panels)
— Calculation and expression of results: Simplification analogous to similar testing standards. No
superfluous formulae, e.g. for simple mean value calculations and percentage indication of measurement
results. Clarification what is necessary or optional. All terms for calculation are in agreement with the
descriptions before and the definitions in clause 3. Calculation and expression of results can be found in
new Annex B.
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
oSIST prEN ISO 23999:2025
DRAFT International Standard ISO/DIS 23999:2024(en)
Resilient floor coverings — Determination of dimensional
stability and curling (vertical deformation) after
exposure to heat
1 Scope
This document specifies methods for determining dimensional stability and curling (vertical deformation)
of resilient floor coverings in all forms (e.g. of sheets, tiles, panels, planks or in rolls) after exposure to heat
and/or after reconditioning.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
dimensional stability
in the context of this document, it is the ability of a resilient floor covering to retain its original linear
dimensions (no elongation or shrinking) after exposure to heat, determined by measuring the linear
dimensional change in machine direction or across machine direction.
3.2
curling (vertical deformation)
vertically concave (+) or convex (-) deformation from the horizontal
3.3
concave deformation
a type of curling (vertical deformation) appearing as uplifted top surface at the outer edge of the specimen;
given as positive value (+)
3.4
convex deformation
a type of curling (vertical deformation) appearing as uplifted/domed top surface in the centre of the
specimen; given as negative value (-)
3.5
machine direction (MD)
direction parallel to the length side of a floor covering manufactured in a continuous process
Note 1 to entry: For rectangular or squared cut specimens (e.g. tiles and planks) where the machine direction could
not be determined the direction of MD can be arbitrarily assigned for the test to enable differentiation from AMD.

oSIST prEN ISO 23999:2025
ISO/DIS 23999:2024(en)
3.6
across machine direction (AMD)
direction across to the length side of a floor covering manufactured in a continuous process
Note 1 to entry: For rectangular or squared cut specimens (e.g. tiles and planks) where the machine direction could be
unknown, the MD can be arbitrarily assigned for the test to enable differentiation from MD.
4 Principle
4.1 General
Three test specimens are initially measured and then placed in an oven at an elevated temperature which
may cause dimensional changes and curl (3.1 - 3.4). After a specific period in the oven and subsequent time of
reconditioning, dimensional stability and the stability against vertical deformation (curling) are measured
again on the same test specimens.
4.2 Dimensional stability
The relative change in linear distance between the same marks or same specific locations of the top surface
layer of a test specimen, measured after exposure to a heat treatment and reconditioning. Depending on
the size of the specimen and the structure of the surface, different measuring devices could therefore be
appropriate.
As a case for special interests, the determination of the change of linear dimensions on hot test specimens,
meaning before reconditioning. As this does not affect the normative measurement of dimensional stability
and curling, it can be determined as an intermediate result on the same test specimens (see Annex A).
4.3 Curling (vertical deformation)
Curling is measured at the highest peaks of the test specimens possibly occurring after the specified heat
treatment in an oven at an elevated temperature and reconditioning in a normal conditioned climate.
An initial vertical deformation of the test specimen (before the exposure to heat) can be measured.
5 Apparatus
5.1 Oven
An oven which shall be thermostatically controlled and ventilated, capable of being maintained at a uniform
temperature with maximum deviations of ±2 °C.
The oven must be capable to place specimens inside in a way that ensures that radiation from the heating
elements does not directly reach the test specimens or support plates (5.2). Therefore, the distance between
the support plates (5.2) and the vertical walls of the oven shall be more than 50 mm and the vertical distance
between the support plates and between the plates and the oven ceiling and base shall be more than 100 mm.
5.2 Support plates
The support plates on which the specimens will be placed for the test shall be of metal, e.g. aluminium or
stainless steel, of dimensions larger than the test specimen, 2,0 mm ± 0,5 mm in thickness. Ensure that the
support plates are kept smooth and polished so that surface friction does not interfere with free shrinkage
or growth of the test specimens. The plates shall be flat and free of convex or concave distortion and fully
support the sample (e.g. a wire rack support plate is not acceptable.).

oSIST prEN ISO 23999:2025
ISO/DIS 23999:2024(en)
6 Measuring devices
6.1 Measurement devices for determination of curling (vertical deformation)
The measuring equipment could be any appropriate apparatus or device capable of measuring small
distances vertical from the support plate (5.2) with a precision of ±0,1 mm and without influencing the test
specimens by any kind of load from the test device itself.
This could be for example:
— a laser measuring device;
— other optical measuring devices;
— tactile measuring devices (e.g. pillar-mounted drop gauge device, feeler gauges or a micrometer).
6.2 Measurement devices for determination of linear dimension changes
All used measuring equipment shall measure with a precision of at least ±0,02 mm.
The measuring equipment could be:
— an optical bench for non-contact dimensional measurements between two marks on the top surface (for
example scores which are carefully made in the surface) or;
— callipers or;
— a block and dial set-up (so-called “block and dial gauge apparatus”, see 6.2.3) as shown in Figures 2, 3 and
4 for tactile measurement at the outer edge of the specimen top layer.
NOTE 1 For many types of optical benches, ensure that the test specimen is properly seated against the base
horizontal index guide when a specific measurement is being taken, otherwise test specimens with concave or convex
edges can be read incorrectly.
NOTE 2 For ready shaped floor covering elements (e.g. tiles and planks) the block and dial gauge apparatus is
appropriate. For test specimens prepared from sheet or roll material, equipment should be used which take measures
from the top surface.
6.2.1 Scoring device
A scoring device, e.g. a single edge razor blade, scalpel or scribe point, can be used to make marks in the top
surface of test specimens made from sheet or roll material or optionally for glue down tiles and planks for
measuring with an optical bench (6.2).
6.2.2 Rigid steel plate
Optional auxiliary device to help flatten concave or convex deformed test specimens from sheet or
roll material or optionally for glue down tiles and planks. A rigid plate of steel, squared and finished, of
dimensions 240 mm × 240 mm with holes to see the measuring marks (examples are shown in Figure 1 and
6) on the top surface of the specimens. If larger format specimens are tested, then the rigid plate should be
of commensurate size and configuration.
6.2.3 Block and dial gauge apparatus (for tiles and planks)
Test device consisting of a support plate in sufficient size with a lay-on edge (block) to be used with a
measuring device (for example a dial gauge, see Figures 2, 3 and 4).
6.2.3.1 Square standard template (optionally)
Standard templates can be used together with the block and dial gauge apparatus (6.2.3) for determination
of deviations in size between the template and a product or a specimen. Figure 2 shows an example of a

oSIST prEN ISO 23999:2025
ISO/DIS 23999:2024(en)
block and dial gauge apparatus with the possible use of standard templates in 4 different sizes and possible
positions of the measuring devices to determine also straightness and squareness. A square standard
template has the nominal side length of a product or a test specimen and should be rectangular. The
deviations from the template sizes before and after heat exposure can show the linear dimensional changes
due to the heat influence.
NOTE 1 A standard template is normally calibrated for straightness, squareness, and length with regard to the
nominal sizes of a product. They can be useful for a quick measurement with always the sam
...