SIST EN ISO 6940:2026

• Abstract:

  This document specifies a method for the measurement of ease of ignition of vertically oriented textile fabrics and industrial products in the form of single or multi-component textile fabrics (coated, quilted, multilayered, sandwich constructions, and similar combinations), when subjected to a small, defined flame.

• Status: Published
• Public Enquiry End Date: 30-Jul-2025
• Publication Date: 18-Jun-2026
• ICS: 13.220.40 - Ignitability and burning behaviour of materials and products
• ICS: 59.080.30 - Textile fabrics
• Technical Committee: ITEK - Textile and textile products
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 10-Jun-2026
• Due Date: 15-Aug-2026
• Completion Date: 19-Jun-2026
• Ref Project: EN ISO 6940:2026 - Textile fabrics - Burning behaviour - Determination of ease of ignition of vertically oriented specimens (ISO 6940:2026, Corrected version 2026-06)

• Refers: SIST ISO 4880:1999 - Burning behaviour of textiles and textile products -- Vocabulary
• Effective Date: 01-Jul-2026
• Revises: SIST EN ISO 6940:2004 - Textile fabrics - Burning behaviour - Determination of ease of ignition of vertically oriented specimens (ISO 6940:2004)
• Effective Date: 25-Sep-2024

SIST EN ISO 6940:2026 is a SIST-published Slovenian standard aligned with EN ISO 6940:2026 and ISO 6940:2026. It specifies a laboratory method for measuring the ease of ignition of vertically oriented textile fabrics and industrial textile products when exposed to a small, defined flame. It is used to compare ignition behaviour of fabrics and fabric assemblies under controlled conditions.

What does SIST EN ISO 6940:2026 specify?

SIST EN ISO 6940:2026 specifies a flame-ignition test for vertically oriented textile specimens. The method covers single fabrics and multi-component textile fabrics such as coated, quilted, multilayered, sandwich constructions, and similar combinations.

The document describes two ignition positions - surface ignition and bottom edge ignition - and uses them to measure how readily a specimen reaches sustained combustion. The introduction also notes that the results are for controlled flame contact and may not apply where air supply is restricted or where exposure is to large sources of intense heat.

The standard is organized into clauses 1 to 13 and three annexes.

Annex	What it covers
Annex A	Normative description and construction of the burner
Annex B	Informative work example for calculating mean ignition time
Annex C	Informative experimental techniques and practical guidance

What are the key requirements of SIST EN ISO 6940:2026?

SIST EN ISO 6940:2026 is built around controlled specimen preparation, controlled flame application, and a reported mean ignition time. The main practical point is that the test is iterative: the operator adjusts flame application time until there are enough ignition and non-ignition outcomes to calculate the result.

Specimens and conditioning

• Clause 7 requires a set of twelve test specimens so that at least five ignition cases and five non-ignition cases can be obtained. A minimum of 10 specimens is needed for each orientation, plus an extra specimen for set-up.
• Specimens are cut to 200 mm by 80 mm, and the length direction is normally vertical with the outer face toward the flame. If a fabric is non-homogeneous or the two surfaces behave differently, those orientations or surfaces are tested separately.
• Clause 8 requires conditioning at 20 °C ± 2 °C and 65 % ± 5 % relative humidity for at least 24 h, then starting each test within 2 min after removal. In practice, handling has to be fast and consistent so moisture changes do not affect the result.

Apparatus and flame setting

• Clause 5 and Annex A require a mounting frame, test specimen holder, template, gas burner, gas supply, and timing devices. The burner must be built to the Annex A design, and the flame can be adjusted within the ranges stated there.
• For surface ignition, Clause 9 sets the burner in a horizontal operating position and adjusts the flame so its horizontal reach is 25 mm ± 2 mm. For bottom edge ignition, the flame height is set to 40 mm ± 2 mm and the burner is inclined toward the lower edge of the specimen.
• Clause 6 requires the test area and equipment to be suitable for burning tests: combustion fumes must not damage the equipment, the surrounding air must not influence the test, and operator exposure to smoke and fumes must be controlled. Air movement at the start of each test has to be less than 0.2 m/s.

Test procedure and result calculation

• Clauses 9 and 10 define the two procedures. The operator records whether length or width direction is vertical, which surface is exposed, and whether surface or bottom ignition is used. Flame application time is then adjusted by 1 s steps based on the previous result.
• The sequence continues until there are at least five ignition and five non-ignition instances. The standard uses a maximum flame application time of 20 s, and longer times are only used if the report states that testing was extended.
• Clause 11 calculates the mean ignition time from the less frequent outcome. The recorded mean is adjusted by 0.5 s, then rounded to the nearest second. In practice, this gives a single reportable threshold for that orientation.
• Clause 12 explains that the method is suited to inflammable materials that sustain combustion, but not to flame-retardant materials that show only limited combustion. That matters because a material can still be reported as not ignited by 20 s even when it behaves differently in other fire tests.

Reporting

• Clause 13 requires the test report to identify the standard used, the gas, date, ambient conditions, specimen identification and pretreatment, orientation, ignition method, specimen-by-specimen results, mean ignition time, any non-ignition at 20 s or above, deviations, and unusual observations. This makes the result traceable and comparable between laboratories.

What terms does SIST EN ISO 6940:2026 define?

SIST EN ISO 6940:2026 uses the vocabulary of ISO 4880 and adds a small set of test-specific terms.

• Flame application time - the time for which the ignition flame is applied to the specimen.
• Afterflame time - the time a material continues to flame after the ignition source has been removed; times below 1.0 s are recorded as zero.
• Ignition - the initiation of combustion.
• Sustained combustion - flaming that gives an afterflame time of 5 s or more, or that reaches the top or vertical edges in less than 5 s.

Who uses SIST EN ISO 6940:2026?

SIST EN ISO 6940:2026 is used by textile test laboratories, manufacturers, converters, and technical staff working with fabrics and textile assemblies. It is relevant for coated, quilted, multilayered, and sandwich constructions, as well as fabrics with seams or trimmings tested in assembly.

Quality managers and buyers use the method when they need a repeatable ignition test result for product comparison, incoming material checks, development work, or specification of textile behaviour under small-flame exposure. It is also useful when a team needs a documented test report that records orientation, surface tested, and the measured mean ignition time.

What changed in SIST EN ISO 6940:2026 from the previous edition?

SIST EN ISO 6940:2026 supersedes EN ISO 6940:2004. The document states that this is a technically revised third edition replacing ISO 6940:2004.

The stated changes are:

• Figure 1 b) was corrected to show the proper angular dimension line and the gas jet tip shape.
• Figure 3 a) and b) were revised to show the test specimen more clearly.
• The revision is described as clarification without structural changes.

Which standards are used with SIST EN ISO 6940:2026?

SIST EN ISO 6940:2026 refers to these standards:

• ISO 4880 - provides the vocabulary for burning behaviour of textiles and textile products, including the basic terms used in Clause 3.
• ISO 6941 - the related test method for measuring flame spread time of vertically oriented specimens; the introduction identifies it as the other closely related method.
• ISO 2768-1 - supplies general tolerances for the dimensions shown in the figures when no individual tolerance is stated.

What does the SIST EN ISO 6940:2026 document contain?

SIST EN ISO 6940:2026 contains the test principle, apparatus requirements, cautionary measures, specimen sampling, conditioning rules, apparatus set-up, test procedures for surface ignition and bottom edge ignition, calculation of mean ignition time, precision guidance, and the reporting items for the test report.

It also includes Figure 1 for the burner construction, Figure 2 for the specimen holder, and Figure 3 for burner position and flame adjustment. Annex A gives the burner design in normative form, Annex B provides a worked calculation example, and Annex C gives practical experimental techniques and safety guidance.

SLOVENSKI STANDARD
01-julij-2026
Tekstilije - Gorljivost - Ugotavljanje nagnjenosti k vnetljivosti navpično vpetih
preskušancev (ISO 6940:2026)
Textile fabrics - Burning behaviour - Determination of ease of ignition of vertically
oriented specimens (ISO 6940:2026)
Textile Flächengebilde - Brennverhalten - Bestimmung der Entzündbarkeit vertikal
angeordneter Proben (ISO 6940:2026)
Textiles - Comportement au feu - Détermination de la facilité d'allumage d'éprouvettes
orientées verticalement (ISO 6940:2026)
Ta slovenski standard je istoveten z: EN ISO 6940:2026
ICS:
13.220.40 Sposobnost vžiga in Ignitability and burning
obnašanje materialov in behaviour of materials and
proizvodov pri gorenju products
59.080.30 Tkanine Textile fabrics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 6940
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2026
EUROPÄISCHE NORM
ICS 13.220.40; 59.080.30 Supersedes EN ISO 6940:2004
English Version
Textile fabrics - Burning behaviour - Determination of ease
of ignition of vertically oriented specimens (ISO
6940:2026)
Étoffes - Comportement au feu - Détermination de la Textile Flächengebilde - Brennverhalten - Bestimmung
facilité d'allumage d'éprouvettes orientées der Entzündbarkeit vertikal angeordneter Proben (ISO
verticalement (ISO 6940:2026) 6940:2026)
This European Standard was approved by CEN on 28 April 2026.

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, Türkiye 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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 6940:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 6940:2026) has been prepared by Technical Committee ISO/TC 38 "Textiles" in
collaboration with Technical Committee CEN/TC 248 “Textiles and textile products” 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 November 2026, and conflicting national standards
shall be withdrawn at the latest by November 2026.
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 6940:2004.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 6940:2026 has been approved by CEN as EN ISO 6940:2026 without any modification.

International
Standard
ISO 6940
Third edition
Textile fabrics — Burning behaviour
2026-05
— Determination of ease of ignition
of vertically oriented specimens
Étoffes — Comportement au feu — Détermination de la facilité
d'allumage d'éprouvettes orientées verticalement
Reference number
ISO 6940:2026(en) © ISO 2026
ISO 6940:2026(en)
© ISO 2026
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 6940:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus . 2
5.6 Timing devices .2
6 Cautionary measure . 4
6.1 Construction of testing equipment . .4
6.2 Location of test apparatus.4
6.3 Health and safety of test operators .4
7 Sampling . 5
7.1 Number of test specimens .5
7.2 Test specimen holder pin location marks .5
7.3 Test specimen size .5
8 Conditioning and testing atmosphere. 5
8.1 Conditioning.5
8.2 Testing atmosphere .5
9 Setting up the apparatus . 6
9.1 Procedure A (Surface ignition).6
9.1.1 Mounting of the test specimen .6
9.1.2 Operating position of the burner .6
9.1.3 Flame adjustment — Horizontal reach .6
9.1.4 Flame position .6
9.2 Procedure B (Bottom edge ignition) .6
9.2.1 Mounting of the test specimen .6
9.2.2 Operating position of the burner .6
9.2.3 Flame adjustment — vertical flame height .7
9.2.4 Flame position .7
10 Test procedure . 8
10.1 Surface ignition .8
10.2 Bottom edge ignition.9
11 Calculation of the mean ignition time . 10
12 Precision . 10
13 Test report . 10
Annex A (normative) Description and construction of the burner .12
Annex B (informative) Calculation of mean ignition time — Work example .13
Annex C (informative) Experimental techniques . 14
Bibliography .15

iii
ISO 6940:2026(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 document 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 38, Textiles, in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 248, Textiles and textile products, in
accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 6940:2004), which has been technically
revised.
The main changes are as follows:
— Figure 1 b) has been corrected with the proper angular dimension line and the shape of the tip of the gas
jet;
— Figure 3 a) and b) have been revised to show the test specimen clear;
— this revision aims to clarify without any structural changes.
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 6940:2026(en)
Introduction
This method is one of two closely related methods of test for the inflammability of textiles. It determines the
[1] [2]
ease of ignition as defined in ISO 4880 . The other method measures flame spread time ISO 6941 .
The method specified in this document assesses the properties of textile fabrics in response to flame contact
under controlled conditions. There is a possibility that results do not apply in situations where there is
restricted air supply or exposure to large sources of intense heat.
The influence of seams on the behaviour of textile fabrics can be determined by this method, the seam being
positioned within the test specimen to be subjected to the test flame. Whenever practicable, trimmings are
tested as part of the textile fabric assembly on which they are, or will be, used.

v
International Standard ISO 6940:2026(en)
Textile fabrics — Burning behaviour — Determination of ease
of ignition of vertically oriented specimens
1 Scope
This document specifies a method for the measurement of ease of ignition of vertically oriented textile
fabrics and industrial products in the form of single or multi-component textile fabrics (coated, quilted,
multilayered, sandwich constructions, and similar combinations), when subjected to a small, defined flame.
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 4880, Burning behaviour of textiles and textile products — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4880 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
flame application time
time for which the ignition (3.3) flame is applied to the test specimen
3.2
afterflame time
length of time for which a material continues to flame under specified test conditions, after the ignition (3.3)
source has been removed
Note 1 to entry: Afterflame time is measured to the nearest second and afterflame times of less than 1,0 s is recorded
as zero.
3.3
ignition
initiation of combustion
3.4
sustained combustion
flaming of the test specimen which gives an afterflame time (3.2) of 5 s or more or which reaches the top or
vertical edges in less than 5 s
4 Principle
A defined flame from a specified burner is applied to the surface or bottom edge of test specimens which are
vertically oriented.
ISO 6940:2026(en)
The mean ignition time is determined as the weighted mean of the measured flame application times
required to obtain sustained combustion of the test specimens.
5 Apparatus
5.1 Mounting frame, constructed to a design capable of holding the gas burner (5.2, see Figure 1) and the
test specimen holder (5.3, see Figure 2) in the specified relative orientation (see Figure 3).
5.2 Gas burner, as described in Annex A, capable of being moved from a standby position, where the tip of
the burner is at least 75 mm from the test specimen, to either the horizontal or inclined operating position
(see Figure 3).
5.3 Test specimen holder, consisting of a rectangular metal frame having a test specimen support pin at
each corner of a rectangle of length 190 mm by width 70 mm (see Figure 2). The pins for supporting the test
specimen have a maximum diameter of 2 mm and a length of at least 26 mm.
NOTE Longer pins can be needed for mounting thick or multilayer test specimens.
For the purpose of locating the test specimen in a plane at least 20 mm away from the frame (see 9.1.1 and
9.2.1), a spacer stub of 2 mm di
...