ISO 13784-2:2020

INTERNATIONAL ISO
STANDARD 13784-2
Second edition
2020-10
Reaction-to-fire tests for sandwich
panel building systems —
Part 2:
Test method for large rooms
Essais de réaction au feu des systèmes de fabrication de panneaux de
type sandwich —
Partie 2: Méthode d'essai pour des chambres de grande taille
Reference number
©
ISO 2020
© 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
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: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope .1
2 Normative references .1
3 Terms and definitions .2
4 Principle .2
5 Types of structure .3
6 Test specimen .3
7 Test room design and construction .3
8 Ignition source .8
9 Apparatus .10
10 Procedure.12
10.1 Initial conditions .12
10.2 Test .13
11 Precision .14
12 Test report .14
Bibliography .16
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 second edition cancels and replaces the first edition (ISO 13784-2:2002), which has been
technically revised.
The main changes compared to the previous edition are as follows:
— All drawings have been updated, as some were unclear and views were incorrect.
— In the Introduction, the reference to ISO/TR 3814 has been updated to ISO/TS 3814.
— In the Introduction, clarification has been added that this document deals with thermal insulating
sandwich panels as well as a widening of the use of products to reflect the current field of applications
of sandwich panels.
— In Clause 3, the term "constant mass" has been removed, as it is not used in this document, and the
term "thermal" in terms of the sandwich panel has been introduced. Terms have been renumbered.
— In Clause 8, Ignition source, the wording and locations have been altered to bring them in line with
the ISO 19075 series and cross-references to a figure have been introduced for clarity (no technical
consequences).
A list of all parts in the ISO 13784 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

Introduction
Fire is a complex phenomenon, its behaviour and effects dependent upon a number of interrelated
factors. The behaviour of materials and products depends upon the characteristics of the fire, the
method of use of the materials and the environment in which they are exposed (for the philosophy of
reaction-to-fire tests, see ISO/TS 3814).
The need for improved insulation of buildings has led to the increased use of thermal insulating
sandwich panel systems in different parts of the building industry. Thermal insulating sandwich panel
systems are applied as external cladding on factory buildings, in internal envelopes with controlled
atmospheres and in cold stores, varying from small rooms to large, coolhouses and warehouses. Other
applications are in modular building rooms and retail premises. These systems can also be used for roof
applications in traditional constructions. Multi-layered panels with other facings (e.g. plasterboard) or
sandwich panel systems can also be applied to walls as internal linings or insulation; however, this is
not within the scope of the ISO 13784 series.
There exist three primary fire-related threats to the walls and ceilings or roofs of a building insulated
with freestanding or frame-supported types of thermal insulating sandwich panel systems:
a) an interior compartment fire impinging directly onto the joints of the wall, typical ignition sources
being welding torches, burning items near the wall and fire in an adjacent room;
b) an external fire or combustibles (rubbish, vegetation, vehicles, etc.) accumulated near the wall;
c) fire spread to outside spaces.
Moreover, such a fire can spread in several ways:
— over a combustible exterior surface;
— by travelling vertically and horizontally through the combustible cores of cavities within the
external wall or ceiling/roof;
— through combustible gases which have developed due to the pyrolysis of the combustible components
and which will ignite on the surface;
— as burning debris or flaming droplets.
This document deals with a simple representation of a fire scenario involving a thermal insulating
sandwich panel system, such as that typified by a local fire impinging directly on the internal face of
a thermal insulating sandwich panel building construction. The test method specified can be used to
provide a large-room scale, end-use evaluation of all aspects of thermal insulating sandwich panel
systems, including constructional techniques (supporting frameworks, jointing detail, etc.).
The test method is intended for evaluating products which, by their nature, are not normally used as

internal linings and are unsuitable for assessment using ISO/TR 9705-2 which evaluates fire growth
from a surface product or ISO 9705-1 (test method). Nevertheless, this document provides a means by
which a freestanding or frame-supported thermal insulating sandwich panel building construction can
be built and evaluated.
Testing of this type can be used for comparative purposes or to ensure the existence of a certain quality
of performance considered to have a bearing on fire performance generally.
The ISO 13784 series consists of the following parts, under the general title "Reaction-to-fire tests for
sandwich panel building systems":
— Part 1: Test method for small rooms;
— Part 2 (this document): Test method for large rooms.
INTERNATIONAL STANDARD ISO 13784-2:2020(E)
Reaction-to-fire tests for sandwich panel building
systems —
Part 2:
Test method for large rooms
SAFETY PRECAUTIONS — In order that suitable precautions can be taken to safeguard health,
the attention of all concerned in fire tests is drawn to the possibility that toxic or harmful gases
can evolve during combustion of test specimens.
The test procedures concerned involve high temperatures and combustion processes, from
ignition to a fully developed room fire. Therefore, hazards can exist for burns, ignition of
extraneous objects or clothing. Operators should use protective clothing, helmet, face-shield
and equipment for avoiding exposure to toxic gases.
Laboratory safety procedures shall be set up which ensure the safe termination of tests on
sandwich panel products. Specimens with combustible content burning inside metallic facings
can be difficult to extinguish with standard laboratory fire fighting equipment. Adequate means
of extinguishing such a fire shall be provided.
When tests are conducted using freestanding or frame-supported constructions, specimens
could emit combustion products from their external faces, especially if joints open up. Specimen
collapse can also occur. Laboratory safety procedures shall be set up to ensure the safety of
personnel with due consideration to such situations.
For construction of the test enclosure using a freestanding structure without structural
framework, because of the size and weight of the individual panels it is strongly recommended
that construction be accomplished within an additional external support framework (e.g.
scaffolding). If the test enclosure is erected in an outside environment, it is further recommended
that the external framework remain in place during the test. The purpose of this framework is
only to avoid collapse of the test room caused by wind action. This additional framework shall
not be used to fix and support the sandwich panels.
1 Scope
This document specifies a test method for evaluating the reaction-to-fire performance of thermal
insulating sandwich panel building systems for large rooms and the resulting flame spread on or
within the thermal insulating sandwich panel building construction when it is exposed to heat from
a simulated internal fire with flames impinging directly on its internal corner. The test method is not
intended for evaluating a product's fire resistance.
This document is applicable to both freestanding and self-supporting and frame-supported thermal
insulating sandwich panel systems, but only to wall and ceiling or roof constructions.
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 13943, Fire safety — Vocabulary
IEC 60584-1, Thermocouples — Part 1: EMF
...