SIST EN ISO 11925-2:2020

SLOVENSKI STANDARD
01-maj-2020
Nadomešča:
SIST EN ISO 11925-2:2011
SIST EN ISO 11925-2:2011/AC:2011
Preskusi odziva na ogenj - Sposobnost vžiga gradbenih proizvodov v
neposrednem stiku s plamenom - 2. del: Preskus z enim gorilnikom (ISO 11925-
2:2020)
Reaction to fire tests - Ignitability of products subjected to direct impingement of flame -
Part 2: Single-flame source test (ISO 11925-2:2020)
Prüfungen zum Brandverhalten - Entzündbarkeit von Produkten bei direkter
Flammeneinwirkung - Teil 2: Einzelflammentest (ISO 11925-2:2020)
Essais de réaction au feu - Allumabilité de produits soumis à l'incidence directe de la
flamme - Partie 2: Essai à l'aide d'une source à flamme unique (ISO 11925-2:2020)
Ta slovenski standard je istoveten z: EN ISO 11925-2:2020
ICS:
13.220.50 Požarna odpornost Fire-resistance of building
gradbenih materialov in materials and elements
elementov
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 11925-2
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2020
EUROPÄISCHE NORM
ICS 13.220.50 Supersedes EN ISO 11925-2:2010
English Version
Reaction to fire tests - Ignitability of products subjected to
direct impingement of flame - Part 2: Single-flame source
test (ISO 11925-2:2020)
Essais de réaction au feu - Allumabilité de produits Prüfungen zum Brandverhalten - Entzündbarkeit von
soumis à l'incidence directe de la flamme - Partie 2: Produkten bei direkter Flammeneinwirkung - Teil 2:
Essai à l'aide d'une source à flamme unique (ISO Einzelflammentest (ISO 11925-2:2020)
11925-2:2020)
This European Standard was approved by CEN on 4 February 2020.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11925-2:2020 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 11925-2:2020) has been prepared by Technical Committee ISO/TC 92 "Fire
safety" in collaboration with Technical Committee CEN/TC 127 “Fire safety in buildings” the secretariat
of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by September 2020, and conflicting national standards
shall be withdrawn at the latest by September 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11925-2:2010.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 11925-2:2020 has been approved by CEN as EN ISO 11925-2:2020 without any
modification.
INTERNATIONAL ISO
STANDARD 11925-2
Fourth edition
2020-02
Reaction to fire tests — Ignitability
of products subjected to direct
impingement of flame —
Part 2:
Single-flame source test
Essais de réaction au feu — Allumabilité de produits soumis à
l'incidence directe de la flamme —
Partie 2: Essai à l'aide d'une source à flamme unique
Reference number
ISO 11925-2:2020(E)
©
ISO 2020
ISO 11925-2:2020(E)
© ISO 2020
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
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Published in Switzerland
ii © ISO 2020 – All rights reserved

ISO 11925-2:2020(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test apparatus . 2
5 Test specimen . 4
5.1 Preparation . 4
5.2 Dimensions . 4
5.3 Products which are not essentially flat . 4
5.4 Number of specimens . 4
5.5 Substrates . 5
6 Conditioning . 5
7 Test procedure . 5
7.1 General . 5
7.2 Preliminary operations . 5
7.3 Testing operations. 5
7.4 Duration of test . 7
8 Expression of results . 7
9 Test report . 8
Annex A (informative) Precision of test method .22
Annex B (normative) Testing not essentially flat end-use products .25
Annex C (normative) Testing perforated end-use products .26
Bibliography .27
ISO 11925-2:2020(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 92, Fire safety, Subcommittee SC 1, Fire
initiation and growth.
This fourth edition cancels and replaces the third edition (ISO 11925-2:2010), which has been
technically revised. It also incorporates the Technical Corrigendum ISO 11925-2:2010/Cor1: 2011.
A list of all parts in the ISO 11925 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 2020 – All rights reserved

ISO 11925-2:2020(E)
Introduction
This fire test method has been developed to define reaction to fire performance of products. The
method specifies a test for determining the ignitability of products by direct small-flame impingement
under zero impressed irradiance using vertically oriented test specimens.
Although the method is designed to assess ignitability, this is addressed by measuring the spread of a
small flame up the vertical surface of a specimen following application of a small (match-sized) flame
to either the surface or edge of a specimen for either 15 s or 30 s. The determination of the production
of flaming droplets/particles depends on whether or not the filter paper placed beneath the specimen
ignites.
INTERNATIONAL STANDARD ISO 11925-2:2020(E)
Reaction to fire tests — Ignitability of products subjected
to direct impingement of flame —
Part 2:
Single-flame source test
1 Scope
This document specifies a method of test for determining the ignitability of products by direct small
flame impingement under zero impressed irradiance using vertically oriented test specimens.
Information on the precision of the test method is given in Annex A (informative).
Information on testing not essentially flat end-use products is given in Annex B (normative).
Information on testing perforated end-use products is given in Annex C (normative).
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 13238, Reaction to fire tests for building products — Conditioning procedures and general rules for
selection of substrates
ISO 13943, Fire safety — Vocabulary
ISO 14697, Reaction-to-fire tests — Guidance on the choice of substrates for building and transport products
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13943 and the following 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 http:// www .electropedia .org/
3.1
product
material, element or component about which information is required
3.2
essentially flat product
product having one of the following characteristics:
a) a planar exposed surface;
ISO 11925-2:2020(E)
b) a planar exposed surface with a surface irregularity that is evenly distributed over the exposed
surface, provided that
— at least 50 % of the surface of a representative square area of 250 mm × 250 mm lies within a
depth of 6 mm from a plane taken across the highest points on the exposed surface, or
— for a surface containing cracks, fissures or holes, these do not exceed 6,5 mm in width or 10 mm
in depth, and that the total area of such cracks, fissures or holes at the surface does not exceed
30 % of a representative square area of 250 mm × 250 mm of the exposed surface
3.3
flaming droplets/particles
material separating from the specimen during the fire test procedure and igniting the filter paper
beneath the specimen
3.4
multi-layered products
product composed of two or more layers of different materials, which can be either substantial and/or
non-substantial
[SOURCE: EN 13501-1:2018-12, 3.1.5 and 3.1.6]
3.5
sustained flaming
persistence of flame for a period greater than 3 s
3.6
ignition
presence of sustained flaming
4 Test apparatus
4.1 Test room, capable of providing an environment at (23 ± 5) °C and a relative humidity of
(50 ± 20) %.
NOTE It has been found that a partially darkened room assists with the perception of small surface flames.
4.2 Combustion chamber, consisting of an enclosure constructed from stainless steel sheets, with
heat-resistant, glazed doors provided for access and observation in at least the front and one lateral
side (see Figure 1). Ventilation of the enclosure shall be free through the square box section base in the
bottom of the chamber. This shall be made of stainless steel of 1,5 mm thickness, 50 mm in height, with
the open square area being 25 mm × 25 mm. To make free ventilation possible, the chamber shall stand
on 40 mm high supports which provide a gap on the lateral sides of the combustion chamber. The air
velocity measured on the central axis in the chimney of the combustion chamber shall be (0,7 ± 0,1) m/s,
measured with the burner only ignited and with the ventilation hood “on”. The combustion chamber
shall be situated under a suitably ventilated hood.
4.3 Ignition source, consisting of burner constructed as shown in Figure 2 and designed so that it can
be used vertically or be tilted at 45° with respect to the vertical axis. The burner shall be mounted onto
a horizontal plate so that it moves smoothly forwards and backwards in a horizontal plane along the
centreline of the combustion chamber.
The burner shall be fitted with a fine adjustment valve to ensure accurate control of the flame height.
4.4 Fuel, consisting of commercial propane of 95 % minimum purity. In order to obtain flame stability
with the burner tilted at 45°, the gas pressure shall be between 10 kPa and 50 kPa.
2 © ISO 2020 – All rights reserved

ISO 11925-2:2020(E)
4.5 Specimen holder, consisting of two stainless steel U-shaped frames. The thickness of the frames
shall be (5 ± 1) mm. The dimensions of the frame shall be as shown in Figure 3. The frame shall hang
vertically from the support (see 4.6 and Figure 7) such that the underside of the specimen is exposed
directly to the flame along its centreline and edges see Figure 8. The two halves of the specimen holder
shall be held together by screws or clamps to prevent the specimen warping.
It is important that the technique of clamping used be capable of restraining the specimen for the total
duration of the test.
NOTE Small pins of approximately 1 mm in length incorporated on the surface of the frame to which the
specimen is attached have been found suitable.
For multi-layered products, a typical test frame as shown in Figure 4 shall be used when carrying out
the prescribed additional set of tests on multi-layer test specimens of thickness greater than 10 mm
according to 7.3.3.2.3.
For the mounting and fixing of loose fill material, the following applies.
a) A specimen holder as shown in Figure 5 shall be used.
b) When making the specimens for testing, the surface of the loose fill material specimen shall be as
even as possible.
c) A wire lacing as shown in Figure 6 shall be used to retain the specimen if material falls from the
specimen holder. A wire of 0,2 mm diameter shall be used to form 11 rows vertically in front of the
opening to hold the loose fill material in place. The wire lacing will have the shape of a harp.
d) If the material is a mixture of various grain sizes, the release of smaller particles from the open
central surface does not justify the use of the harp.
e) It is deemed sufficient to carry out the tests with a surface flame attack. Edge flame attack tests are
not necessary.
4.6 Support, consisting of a vertical stand to which the specimen holder is attached such that it hangs
vertically and exposes its open edge containing the specimen to the burner flame (see Figure 7).
The distance between the underside of the specimen and the top of horizontal plate above the metal grid
shall be (125 ± 10) mm for edge flame impingement and (85 ± 10) mm for surface flame impingement.
4.7 Timing device, capable of recording elapsed time to the nearest second and which shall be
accurate to within 5 s in 1 h.
0 0
4.8 Template, consisting of one metal plate 250 mm long and 90 mm wide.
() ()
−1 −1
4.9 Flame checking devices.
4.9.1 Flame-height measuring device, capable of indicating a flame height of 20 mm (see Figure 9)
when located against a fixed point of the burner. The tolerance on the flame-height measuring device
shall be ±0,1 mm.
The flame height shall be measured from the upper edge of the burner to the yellow tip of the flame.
The outer blue halo of the flame may not be considered. This check shall be conducted before testing
each specimen.
4.9.2 Burner spacer for edge flame impingement, removable, 16 mm long, which can be mounted
at the burner orifice to check the distance from the pre-set flame contact point on the specimen (see
Figure 10).
ISO 11925-2:2020(E)
4.9.3 Burner spacer for surface flame impingement, removable, cone-shaped, which can be
mounted at the burner orifice to check the fixed distance of 5 mm between the burner edge and specimen
surface (see Figure 11).
4.10 Anemometer, thermal anemometer with an accuracy of ±0,1 m/s, for measuring the airflow
velocity in the upper outlet of the combustion chamber (see 4.2 and Figure 1).
4.11 Filter paper and tray. The paper shall be new undyed filter paper with a mass/unit area of
(75 ± 15) g/m and an ash content of less than 0,1 %. The tray shall be 100 mm × 50 mm and 10 mm deep
and made of aluminium foil. The tray is placed beneath the specimen holder and is replaced between tests.
4.12 Apparatus to allow observation of the reverse face of the specimen. For some materials, it is
sometimes necessary to observe the flame on the reverse face of the specimen as well as the exposed face.
Provision shall therefore be made to enable the operator to view both sides of the specimen at the
same time. One method by which this may be achieved is to place a mirror such that the backside
of the specimen can be monitored. The mirror shall not be placed above the specimen, in order to
avoid disturbance of the airflow. The design and location of the mirror shall be appropriate for the
construction of the equipment and the available ambient lighting. The result observed on the reverse
face shall be treated as if it occurred on the front side.
5 Test specimen
5.1 Preparation
The test specimen shall be cut from a sample which is representative of the product to be tested using
the templates specified in 4.8.
5.2 Dimensions
+2 +2
The dimensions of the test specimens shall be 250 mm long by 90 mm wide.
() ()
−2 −2
Specimens normally having a thickness of 60 mm or less shall be tested using their full thickness.
Specimens normally having a thickness greater than 60 mm shall be reduced to a thickness of 60 mm
by cutting away the unexposed surface. If it is necessary to reduce the specimen size in this manner, the
cut surface shall not be exposed to the flame.
For products which are normally manufactured in sizes less than
...