EN 60695-11-20:1999

SLOVENSKI STANDARD
01-september-2000
Preskušanje požarne ogroženosti - 11-20. del: Preskusni plameni - Preskusne
metode s 500-vatnim plamenom (IEC 60695-11-20:1999)
Fire hazard testing -- Part 11-20: Test flames - 500 W flame test methods
Prüfungen zur Beurteilung der Brandgefahr -- Teil 11-20: Prüfflammen - Prüfverfahren
mit einer 500-W-Prüfflamme
Essais relatifs aux risques du feu -- Partie 11-20: Flammes d'essai - Méthodes d'essai à
la flamme de 500 W
Ta slovenski standard je istoveten z: EN 60695-11-20:1999
ICS:
13.220.40 Sposobnost vžiga in Ignitability and burning
obnašanje materialov in behaviour of materials and
proizvodov pri gorenju products
29.020 Elektrotehnika na splošno Electrical engineering in
general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

NORME
CEI
INTERNATIONALE
IEC
60695-11-20
INTERNATIONAL
Première édition
STANDARD
First edition
1999-03
PUBLICATION FONDAMENTALE DE SÉCURITÉ
BASIC SAFETY PUBLICATION
Essais relatifs aux risques du feu –
Partie 11-20:
Flammes d’essai –
Méthodes d’essai à la flamme de 500 W
Fire hazard testing –
Part 11-20:
Test flames –
500 W flame test methods
 IEC 1999 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
CODE PRIX
PRICE CODE R
Pour prix, voir catalogue en vigueur
For price, see current catalogue

60695-11-20  IEC:1999 – 3 –
CONTENTS
Page
FOREWORD. 5
INTRODUCTION . 7
Clause
1 Scope . . 11
2 Normative references . 11
3 Definitions . . 13
4 Principle . 13
5 Significance of test . 15
6 Apparatus . 15
7 Specimens . 19
8 Test method . 19
Annex A (informative) Precision of the test method . 35
Bibliography .37
Figures
1 Vertical burning test for bar specimens . 27
2 Horizontal burning test for plates . 29
3 Burner mounting block . 31
4 Test specimens . 33
Tables
1 5V burning categories. 23
A.1 Precision data on the afterflame time t after the fifth flame application. 35
A.2 Precision data on the afterflame time t and/or afterglow time t after the fifth flame
1 2
application. 35

60695-11-20  IEC:1999 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
FIRE HAZARD TESTING –
Part 11-20: Test flames – 500 W flame test methods
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC national Committee interested in the subject dealt with may
participate in this preparatory work. The IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60695-11-20 has been prepared by IEC technical committee 89:
Fire hazard testing, and by subcommittee 4: Burning behaviour, of ISO technical committee 61:
Plastics.
This first edition replaces the pertinent parts of the first edition of IEC 60707, published in
1981.
It cancels and replaces ISO 10351, published in 1992.
This standard has the status of a basic safety standard in accordance with IEC Guide 104.
The text of this standard is based on the following documents:
FDIS Report on voting
89/316/FDIS 89/327/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
Annex A is for information only.
The contents of the corrigendum of February 2000 have been included in this copy.

60695-11-20  IEC:1999 – 7 –
INTRODUCTION
When considering the use of the tests in this International Standard, it is important to
distinguish the term “end-product test”, meaning a fire hazard assessment test on a completed
product, piece part, component or subassembly, from the term “pre-selection test”, meaning a
combustion characteristic test made on a material (piece part, component or subassembly).
Pre-selection tests on materials normally use test pieces that have standardised shapes, such
as a rectangular bar or sheet, and are frequently prepared using standardised moulding
procedures.
It is emphasized that data using the pre-selection tests given in this standard need careful
consideration to ensure their relevance to the intended application and to avoid misuse and
erroneous interpretation. The actual fire performance of a part or product is affected by its
surroundings, design variables such as shape and size, fabrication techniques, heat transfer
effects, the type of potential ignition source and the length of exposure to it. It is important to
bear in mind that these properties may also be affected by foreseeable use, abuse and
environmental exposure.
The advantages of a pre-selection procedure are listed below.
a) A material, which reacts more favourably than another when tested as a standard test
specimen, will usually also react more favourably when used as a finished part in the
product, provided that possible synergistic effects are avoided.
b) Data concerning relevant combustion characteristics can aid the selection of materials,
components and subassemblies during the design stage.
c) The precision of pre-selection tests is usually higher, and their sensitivity may be superior
when compared with end-product tests.
d) Pre-selection tests may be used in a decision-making process directed to minimize fire
hazards. Where applicable for the purpose of fire hazard assessment, they may lead to a
reduction in the number of end-product tests, with a consequent reduction in the total
testing effort.
e) When fire hazard requirements need to be upgraded quickly, it may be possible to do this
by upgrading the requirements of a pre-selection test before modifying the end-product test.
f) The grading and classification obtained from the pre-selection test results may be used to
specify a basic minimum performance of materials used in product specifications.
It should be noted that, when pre-selection testing is used to replace some of the end-product
testing, it is necessary to fix an increased margin of safety in an attempt to ensure satisfactory
performance of the end-product. End-product testing may avoid restrictions in innovative
design and in economic material selection imposed by a pre-selection procedure.
Consequently, following a pre-selection procedure, it may be necessary to implement a value
analysis on the end-product, in order not to overspecify the product beyond what is strictly
needed.
For electrotechnical products, IEC 60695-1-1 indicates that the risk of fire is present in any
electrical circuit which is energized. With regard to this risk, the objective of component circuit
and equipment design, and of the choice of materials is to reduce the likelihood of fire, even in
the event of foreseeable abnormal use, malfunction or failure. The practical aim is to prevent

60695-11-20  IEC:1999 – 9 –
ignition due to the electrically energized part but, if ignition and fire occur, to control the fire,
preferably within the bounds of the enclosure of the electrotechnical product.
The best method for testing electrotechnical products with regard to fire hazards is to duplicate
exactly the conditions occurring in practice. In most instances this is not possible. Accordingly,
for practical reasons, the testing of electrotechnical products with regard to fire hazard is best
conducted by simulating as closely as possible the actual effects occurring in practice.
IEC 60695-1-3 provides that pre-selection may be made on the basis of specified tests and by
the use of specifications of the necessary resistance to fire and related combustion
characteristics. It also outlines guidance that is intended to relate the specific function of the
electrotechnical product, its subassemblies and its parts to the tested properties of materials,
and to demonstrate the significance and the limitations of such a pre-selection procedure.
ISO/TR 10840 summarises specific problems associated with the fire testing of plastics, which
should be taken into account when assessing and interpreting test results.

60695-11-20  IEC:1999 – 11 –
FIRE HAZARD TESTING –
Part 11-20: Test flames – 500 W flame test methods
1 Scope
This part of IEC 60695 specifies a small-scale laboratory screening procedure for comparing
the relative burning behaviour of specimens made from plastics and other non-metallic
materials, as well as their resistance to burn-through when exposed to a flame ignition source
of 500 W nominal power. This method is applicable to both solid materials and cellular plastic
materials having an apparent density of 250 kg/m or greater when determined in accordance
with ISO 845. It does not apply to thin materials that shrink away from the applied flame without
igniting, for which ISO 9773 should be used.
The test method described is intended to characterize material performance, for example for
quality-control purposes, and is not intended to assess the behaviour to fire of building
materials or furnishings. It may be used for the pre-selection of a material, provided that
positive results are obtained at a thickness which equals the smallest thickness used in the
application. The results obtained provide some information about the behaviour of plastic
materials in service, but can never by themselves assure safe performance in service.
NOTE – Test results are influenced by material components, e.g. pigments, fillers, and fire retardants, and
properties such as the direction of anisotropy and the molecular mass.
This test method provides a classification system (see 8.4) which may be used for quality
assurance or the pre-selection of component materials of products.
2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60695. For dated references, subsequent amendments
to, or revisions of, any of these publications do not apply. However, parties to agreements
based on this part of IEC 60695 are encouraged to investigate the possibility of applying the
most recent editions of the normative documents indicated below
...