ISO/TR 12470-1:2017

TECHNICAL ISO/TR
REPORT 12470-1
First edition
2017-11
Fire-resistance tests — Guidance
on the application and extension
of results from tests conducted on
fire containment assemblies and
products —
Part 1:
Loadbearing elements and vertical
and horizontal separating elements
Essais de résistance au feu — Recommandations pour l'application
et l'extrapolation des résultats d'essais réalisés sur les produits et
assemblages d'endiguement du feu —
Partie 1: Éléments porteurs et éléments horizontaux et verticaux de
séparation
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Principles of the field of application . 4
4.1 Direct application . 4
4.2 Extended application . 4
4.2.1 Rules of extended application . 5
4.2.2 Calculations and computer programs used in extended applications . 5
4.2.3 Judgements in extended applications . 5
4.3 Project specific application . 5
5 Common factors which influence the field of application of all elements .6
5.1 Manufacture and materials . 6
5.1.1 General. 6
5.1.2 Direct application . 6
6 Loadbearing elements . 6
6.1 Walls . 7
6.1.1 General. 7
6.2 Direct application . 7
6.2.1 Common parameters of all forms of wall construction . 7
6.2.2 Extended application . 9
6.3 Floors.11
6.3.1 General.11
6.3.2 Direct application .11
6.3.3 Extended application .13
7 Non-loadbearing elements .15
7.1 Vertical partitions .15
7.1.1 General.15
7.1.2 Direct application .15
7.1.3 Extended application .16
7.2 Horizontal “partitions” ceiling membranes .20
7.2.1 General.20
7.2.2 Direct application .20
7.2.3 Extended application .21
8 Evolution of testing and summary of quantifiable approaches .25
8.1 Improvement of testing methodologies .25
8.1.1 Existing test methods .26
8.1.2 Test using reduced-size specimen (reduced-scale test) .27
8.1.3 Selection of the specimen .27
8.2 Mathematical modelling of thermal and mechanical response .28
8.2.1 Level 1 — Numerical regression analysis .28
8.2.2 Level 2 — Graphical approach .28
8.2.3 Level 2 — 3D interpolation .28
8.2.4 Level 3 — Physical equation analysis .29
8.2.5 Level 4 — Finite element methods .29
8.2.6 Level 5 — Integrated interactive analysis .30
8.3 Expert system based upon the use of performance coefficients.30
8.3.1 Concept .30
8.3.2 Establishing the coefficients .31
8.3.3 Obtaining benefit from excess performance .31
Annex A (informative) Principles of using expert judgement to establishing to the extended
field of application .32
Bibliography .39
iv © ISO 2017 – All rights reserved

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 on 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 the following
URL: www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 92, Fire safety, Subcommittee SC 2, Fire
containment.
A list of all parts in the ISO 12470 series can be found on the ISO website.
Introduction
Fire resistance tests on building components are necessary to establish their behaviour against pre-
determined criteria when exposed to a representative fully developed fire and to provide information
that may be used in determining the fire safety of buildings. For several decades, people have accepted,
by means of test results only, the possibility of grading the components. Now, due to the enhancement
of our knowledge and the complexity of buildings, it is necessary to be able to give a more accurate
assessment of the components used in buildings, particularly with the growth of the use of functional
approaches to designing fire safe structures.
The need to understand how the element will perform at a different size, with different levels of
restraint, etc. is vital when applying the results of the fire tests in a life safety situation, especially
those where the fire safe solution has been generated using fire safety engineering techniques rather
than using a code compliant solution. This does not negate the need to predict any changes that may
result from changes to the test construction when complying with building code solutions, but these
codes may themselves provide solutions that take into account the influence or impact of changes, and
indeed the guidance given in this document may be used by the code writers to produce such guidance.
Even with the knowledge available to assess the behaviour of a given constructional element, whatever
its design or its size, we will still be some distance away from establishing the complete behaviour of a
building in a real fire.
The philosophy of only grading elements into different fire resistance categories may not give any
indication about how the element actually behaves when heated. By studying and analysing the data
from fire resistance tests, it will be possible, using the guidance within this document, to obtain a
basic understanding of the influence of the main parameters on the element performance during fire
resistance tests.
In practice, tests do give much useful information which can be used for interpolation and extrapolation
of the results.
The original version of ISO/TR 12470 was published by ISO/TC 92/SC 2 in 1998. This Technical Report
provided a methodology identifying how the results of fire resistance tests carried out in the standard
furnaces could be modified to apply to the elements as they may be used in practice. In some cases, the
results of the test may need to be reduced to reflect any increases in the degree of difficulty that the
final application represents or alternatively, modifications/enhancements may need to be made to the
construction in order to maintain the performance level(s).
In the intervening years since the original Technical Report was prepared, a greater understanding has
developed as to what the changes are likely to be and how they may be quantified. Some of the work in
Comité Européen de Normalisation (CEN) has aided this process and in particular, the principles given
in Annex A remained unpublished by CEN but were developed in one of the technical Work Groups of
CEN/TC 127. This revision represents the current state-of-art in respect of the objectives of the original
1998 version of ISO/TR 12470.
In this document, all assessments of extended application are based on standard time/temperature
conditions and on isolated elements, with no interaction with the adjacent elements.
Also, ageing and weathering are not covered.
The ISO/TR 12470 series is published in two parts:
Part 1: Loadbearing elements and vertical and horizontal separating elements;
Part 2: Fire resistant door assemblies, glazing, services and service penetration.
vi © ISO 2017 – All rights reserved

This document is divided into two sections:
— Guidance on direct and extended application of test results for various elements used in buildings,
the major parameters of which would be assessed by calculation or expert judgements based upon
the methodology and discipline given in Annex A.
— Current state-of-art and possible evolution:
— improvement of testing methodologies to give a better prediction of the performance of various
sizes and designs of a given element;
— mathematical modelling which can be used by experts to give their judgement;
— expert systems which could take into account the interaction of various factors in an assessment.
TECHNICAL REPORT ISO/TR 12470-1:2017(E)
Fire-resistance tests — Guidance on the application
and extension of results from tests conducted on fire
containment assemblies and products —
Part 1:
Loadbearing elements and vertical and horizontal
separating elements
1 Scope
This document explains a methodology to determine the applicability of the results of fire resistance
tests to actual applications.
It is applicable to those loadbearing and simple vertical and horizontal separating elements for
which there is an ISO standard test procedure based upon the ISO 834 series for determining the fire
resistance of a representative sample of the construction proposed for use in a specific building or just
for general use. These elements are:
— loadbearing elements;
— non-loadbearing elements:
— partitions:
— stud construction partitions;
— composite panel/SIPS partitions;
— ceiling membranes (horizontal partitions):
— jointed ceilings;
— composite panel ceilings.
Direct and extended applications of test results are the two possible ways to ensure that a modified
element has an acceptable probability of obtaining the same fire rating as that of the original tested
specimen. In both cases, these applications generally refer only to the fire rating that the building
element can expect to reach if it, or a representative sample of it, were to be tested in a furnace according
to the standard fire test conditions used in the reference test.
One of the most common variations is in respect of the size of the element in use. Fire resistance testing
furnaces have size restrictions and as a consequence, there is little confidence that the result obtained
on an element of construction tested in accordance with the standard methods will behave in a similar
manner when installed in the final building.
This document does not provide guidance on the application and extension of results arising from
testing carried out on door and window assemblies, linear gaps or service penetration seals, which is
covered in ISO/TR 12470-2.
For some, but not all of the critical parameters, a summary of the possible influences is incorporated in
the given examples.
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 834 (all parts), Fire resistance tests — Elements of building construction
ISO 13943, Fire safety — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 834 (all parts) and
ISO 13943 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
direct application
application that identifies the modifications that can be made to the design of the tested element
without reducing its fire rating
Note 1 to entry: These possible modifications are based on obvious knowledge and do not need further evaluation.
In every case, it is at least assumed that the basic material(s) used for the construction of the tested sample will
not be changed.
Note 2 to entry: Direct application defines the variation(s) in the construction and the limits of use for the
element which, without further analysis, are covered by the result of a test in accordance with the ISO 834 series.
Direct application is arrived at by the application of simple rules (3.4) that are known, or considered by the fire
community, to give equal or improved fire resistance performance by the users. The rules can be applied by non-
fire experts.
Note 3 to entry: Only results from one test report can be used when considering a change of an element. Any
combination and use of two or more tests reports or other technical sources should be regarded as extended
application (3.2) and hence dealt with accordingly.
3.2
extended application
application that generally requires an assessment by a fire expert either in developing rules (3.4) of
application for more general application by others, or evaluating the results of fire engineering
calculations, or for making a judgement in specific cases
Note 1 to entry: In every case, it should be taken into consideration that extended application may take into
account the difference between the result of the original test and the fire resistance required for the untested
element.
Note 2 to entry: Extended application defines and specifies the variations in the construction and establishes
the limits of use for an element that has been tested according to the appropriate ISO standard, based upon an
analysis by fire experts. The extended application can use the results from one or more test reports and can
be based upon rules, calculations and expert judgement (3.6). As a result of the extended application, the fire
resistance classification of an element with respect to defined performance characteristics may be maintained,
increased or decreased when used in practice.
2 © ISO 2017 – All rights reserved

3.3
project specific application
application that uses a mixture of established validated calculations/computer models (if they exist and
are appropriate) together with judgements made by suitably qualified persons (normally a professional
badged engineer or a corporate member of a learned professional body)
Note 1 to entry: Because the application will, in these circumstances, require an understanding of both the
structural response and the fire dynamics of the building in question, it is inevitable that the solution will involve
an element of fire safety engineering.
3.4
rule
quantitative factor (3.9) that can be applied to the result of tests when defining the limits of application
for which justification exists as a result of research and testing
Note 1 to entry: Rules are primarily used in determining the direct application (3.1) of the result as its application
does not generally require specialist knowledge.
Note 2 to entry: It is anticipated that these rules be established by the specialist (or ad hoc) groups preparing
the specific standards based upon public domain knowledge and developed by industry consortia or trade
associations for specific elements for which the members have appropriate interest and knowledge, particularly
in Europe initially. After some experience, the results of calculations and judgements may become rules.
3.5
calculation in support of extended application
calculation method that can be applied to one or more parameters of a tested construction and which
are based on existing physical laws or which have been empirically validated and which form part of
the process of defining the extended application (3.2)
Note 1 to entry: If this term has a definition elsewhere, then it should be used but possibly modified to include
this specific use.
3.6
expert judgement
qualitative process performed by fire experts when the complexity of the influence is beyond the
scope of rules (3.4), to establish the resultant effect of a variation in one or more parameters, on the
classification awarded
3.7
construction parameter
aspect of the design and construction of an element that may be varied and which may result in a
change in the fire resistance performance, e.g. a change in one or more of the dimensions of a stud in a
stud framed separating element
3.8
thermal and mechanical parameter
aspect of the conditions of a test that may vary in practice and influence the classification system given,
e.g. the pressure differential that will exist at the top of a larger element than existed at the top of the
specimen when tested
3.9
factor
one of the possible variations that may be applied to a parameter, e.g. a change in the stiffness as a
result of a dimensional change in the member or a component within the element
3.10
factor influence
one of the potential causes of a change in the fire resistance recorded by test, with respect to one or
more of the criteria, when a factor (3.9) is changed, e.g. an increase in the loadbearing capacity R as a
result of an increase in stiffness
4 Principles of the field of application
The field of application from the result of a fire resistance test has at least three possible components:
(1) direct application, (2) extended application and (3) project specific application.
The process of determining the direct application and extended application of the fire resistance
rating of a tested construction normally assumes that the performance is evaluated against the
temperature/time and differential pressure conditions given in the appropriate ISO fire resistance
testing standard (based upon the ISO 834 series or the national, regional equivalent), as this is generally
what is referenced in national prescriptive legislation. The variations between the tested specimen and
the “as-built” construction will therefore be restricted to:
— variations in the size of the construction;
— variations in the materials and methods of construction;
— variations in the restraint and fixity;
— variations in the load carried (if any).
In this situation, only the constructional parameters given in A.2.2 need to be taken into account.
In practice, there will be a need to predict the performance of a structure when it is exposed to
different fire exposure conditions, in terms of the temperatures reached after certain durations and
with greater or lesser pressure differentials. Generally, the parameters will be analysed by means of
a fire engineering analysis which is outside of the scope of this document, but the parameters listed in
A.2.1 may be appropriate for use in an expert judgement analysis of these characteristics.
For each type of element of construction, the application of test results will be considered under three
conditions: (1) direct application, (2) extended application and (3) project specific fields of application.
Changes in materials and methods of construction can have significant influences on the fire resistance.
Because the advice and recommendations are common to all elements, those aspects are dealt with
separately under 5.1 to avoid repetition. The user of this document should consider these aspects
in all applications of results whether direct applications, extended applications, or project specific
applications.
4.1 Direct application
The direct application will normally involve the application of “rules” that are given as part of the test
standard or in a document directly associated with the test standard. It requires no knowledge of the
process of determining the fire resistance other than an understanding of the criteria and the general
terminology.
Where there is more than one change in any proposed construction/installation, two “direct
application” rules should not be applied automatically and the two should be compared as part of an
extended application.
4.2 Extended application
Determining the extended application of the fire resistance is a more complex matter and will generally
need to be undertaken by “experts” who understand the mode of failure and the factors that lead to such
a failure. There are three common methods used by practitioners to establish the extended application
of the fire resistance of elements of construction and these are:
— application of locally validated rules, especially within Europe;
— use of established validated calculations/computer models, where they exist;
— use of technical judgement by suitably qualified persons.
4 © ISO 2017 – All rights reserved

NOTE In Europe, as part of the application of products within the context of the Construction Products
Regulations (CPR), the extended application is determined by means of Extended Application (EXAP) standards,
for use in the process of classification of products to enable CE marking. These EXAP standards cannot be used in
the context of generating a fire safe environment without further analysis.
4.2.1 Rules of extended application
These would be applied universally even by persons without expertise in fire as part of the direct
field of application of the test result for a given family or products. These rules may require cold
state calculation. The quantification of these rules would be agreed universally based upon validated
experience related to generic constructions or components. This could cover size changes, number of
joints, size of glazing, etc.
Throughout this document, the clauses covering rules frequently express the acceptable change in
terms of un-quantified percentages indicated by the letter “X” and an appropriate suffix.
This allows national regulatory authorities to insert their own acceptable limits which will relate to
their established fire safety philosophy.
Authorities are encouraged to support the necessary research towards internationally harmonized
validated values.
4.2.2 Calculations and computer programs used in extended applications
These would be used by an expert in determining the field of application but will mainly be restricted
to the properties indicated below:
— non-loaded elements: this would be restricted to the calculation of temperature rise and deflection
of "simple" components and elements;
— loadbearing elements: in addition to the properties permitted for non-loaded elements, calculation
at elevated temperature could be permitted for the loadbearing capacity for well documented
materials (steel, concrete, etc.) and for statically determined elements.
In every case, the calculations and/or models used by the experts, whatever their source (purchased
from software manufacturers or developed by the assessing body), have to be fully validated by
comparison with existing test results and by sensitivity analysis of the various parameters.
4.2.3 Judgements in extended applications
For a test result to be extrapolated to cover changes outside those for which calculations or written
rules are applicable, the result may still apply subject to some expert judgement being made. The section
on judgements highlights the matters that need to be considered and to be explained by the body or
person responsible for making such judgements. Generally, components of a construction element
could be changed, provided it can be shown that this does not reduce the fire resistance. It should be
demonstrated that the interaction of a new component with other components will not adversely affect
the performance of the tested construction. If the fire resistance obtained in a fire test is greater than
the fire resistance time aimed at in the assessment, there is an overrun in fire resistance performance.
If this overrun, obtained in the fire resistance test, is substantial, then it can be used as a trade-off, i.e. if
a significant overrun has been achieved, it will generally be possible to allow for a greater change in the
construction than if the claimed fire resistance time has only just been met in the fire resistance test.
In order to bring greater consistency to the judgemental process, it is recommended that this process
follows the methodology given in Annex A.
4.3 Project specific application
This document has described the manner by which variations in the construction of an element which
has been designed to provide fire resistance can be accepted or rejected, which utilizes the main
parameters of the materials and components incorporated in the proving test. However, it may be
possible in certain applications to provide more generous extensions to the field of application because
it has been possible to utilize certain factors relating to the “in-use” application, e.g. significantly
enhanced restraint or an uneven distribution of the applied load. In such cases, the derived direct or
extended field of application is only valid for the specific project from which these inputs have been
derived. Because of the bespoke nature of the inputs, the field of extended application only applies to
the use of the element in question within the application for which it was designed. As a consequence,
the field of application is known as project specific.
5 Common factors which influence the field of application of all elements
The advice in this clause applies to all subsequent groups of elements.
5.1 Manufacture and materials
5.1.1 General
For certain applications, even small changes in either the materials or the methods of manufacturing
may result in large changes in fire resistance, e.g. the depth of the edge cover on monolithic fire
resisting glasses. The result from a fire resistance test may be used to support an evaluation of the
performance of a similar untested element or it may be used to justify an element in use without any
further calculations, or the application of rules, if the manufacture of the element follows the guidance
given in 5.1.2. Where the construction is not covered by the direct application, then the calculations or
application rules need to be applied as indicated.
Additionally, there are quality control and certification schemes in some countries. Control procedures
ensure that the untested construction is equivalent to the tested construction. Any relaxation of these
procedures may only be undertaken if it can be established that they only influence non-critical aspects
of the construction (e.g. colour, texture, etc.). Evidence of the effect should be available if the control of
the “critical” processes or materials is involved. Reduced scale fire resistance tests may be used for this
purpose subject to the changes not affecting distortion.
The information given for direct applications and extended applications has to be used for every
construction element.
5.1.2 Direct application
a) The quality control procedures are not reduced.
b) The manufacturing/construction procedures remain unchanged.
c) Constituent materials, admixtures, preservatives, flame retardants, adhesives, etc. remain
unchanged.
6 Loadbearing elements
Basic loadbearing elements made from materials for which there is a large quantity of historical
data giving the fire resistance with respect to the loadbearing capacity of these materials/structural
elements in question, e.g. metal (and in particular steel), wood, concrete and masonry, are almost
never the subject of fire resistance testing. The performance of such materials/elements is established
by means of design codes which provide calculation methods for both the hot and ambient load cases
which have their extended application built into the methodology of the design code(s).
As a consequence, no specific guidance is given in this document related to the direct and extended
application of these basic forms.
Fire resistance testing does take place on non-separating elements, however, on various “materials”
which are applied to the surface of elements which do need to have their natural fire resistance
enhanced, e.g. intumescent coatings, boards and sprayed protective materials and these do need to
6 © ISO 2017 – All rights reserved

have an extended field of application produced in order to establish the limit(s) of their contribution.
These materials are relatively complex and most of them have bespoke extended application methods
which are designed to permit variations in thickness or material characteristics to be used and provide
cost-effective improvements to the loadbearing capacity of the original elements.
These bespoke methods do not have the same general principles as are used for non-loadbearing
elements, but in Clause 8, there is a description of these bespoke methods and some limited guidance on
their application.
Loadbearing walls and floors are, however, often tested, albeit masonry and concrete elements are
less likely to be tested than site-assembled or pre-manufactured and transported elements which are
again generally designed against material codes and standards. When no such guidance exists, then the
following guidance is appropriate.
6.1 Walls
6.1.1 General
The results from a fire resistance test may be used to support an evaluation of the performance of
variations to the construction of the tested loadbearing walls without any further calculations, the
application of more complex rules or the use of judgements, if the construction complies with the
statements given in 4.1. Where the construction does not comply with the direct application, then the
calculations or the judgements need to be applied as indicated in 4.2 or, if in Europe, the appropriate
extended application rules are applied if the product is to be CE marked.
The relevant performance criteria are loadbearing capacity, integrity (measured by gap gauge, ignition
of cotton pad, or sustained flaming) and insulation (increase in the average and maximum unexposed
face temperature).
Loadbearing walls come in a variety of common forms:
— brickwork or blockwork;
— cast-concrete;
— studded construction (manufactured off or on site) – low loads;
— composite panels/structural insulated panels (SIPS) – very low loads.
The guidance in respect of these has to reflect their different methods of construction.
6.2 Direct application
The results of a fire resistance test are deemed to be applicable to a similar form of untested vertical
partition provided that all the following are satisfied.
6.2.1 Common parameters of all forms of wall construction
a) The height is not increased.
b) The edge conditions are unchanged and for a wall tested with all edges restrained, no increase in
width is permitted.
c) For a wall only fixed at the top and bottom and tested at least with one edge free, wider elements
are allowed.
d) Openings in walls should be controlled such that their size and number in any equivalent area are
not increased, the method of protecting the opening is unchanged and their position relevant to
any critical component of the construction (if there are any) is not decreased.
6.2.1.1 Brickwork or blockwork walls
a) The thickness of the wall, including any cavity, if appropriate, should not be reduced.
b) The thickness of the individual bricks or blocks should not be reduced.
c) The number of mortar joints per m height should not be decreased.
d) The density of the individual bricks or blocks may not be reduced nor be increased by more
than 25 %.
e) The strength of any mortar should not be reduced.
f) The number and strength of any ties in a twin leaf wall should not be reduced in strength and the
number and the distribution of them should not be changed significantly.
g) The number of load application points should not be reduced.
6.2.1.2 Cast-in place or concrete slab walls
a) The density of the concrete should not be reduced or be increased by more than 25 %.
b) The nature and distribution of any reinforcing steel should not be less in quantity or strength.
c) The number of load application points should not be reduced.
6.2.1.3 Stud constructed partitions (metal and timber)
a) Thermal insulation between studs is not changed in type or reduced in thickness and density at
any point.
b) The thickness of component materials (e.g. linings, boards, studs) is not reduced.
c) The slenderness ratio of the studs is not worse.
d) The stud spacing is not increased.
e) The size of any panel or board forming the lining should not be reduced, i.e. there should not be any
more gaps/joints between boards.
f) On a board lined system, the distance between the fixings of the board edges is not increased.
g) The length of any fixing is not reduced.
h) The type and nature of any fixings are unchanged.
6.2.1.4 Composite panels/SIPS constructed partitions
a) The thickness (gauge) of any facing should not be reduced, nor should the facing material be
changed.
b) The insulating core should not be changed in type/density but thickness may be increased.
c) The method of attaching the facings to the core remains unchanged.
d) The method of jointing panels to each other should be unchanged.
e) The number of load application points should not be reduced.
8 © ISO 2017 – All rights reserved

6.2.2 Extended application
6.2.2.1 Rules
Except in the context of classification in CEN (see EN 13501-2), it is not possible to extend the application
of a test result on a wall by the application of pre-determined rules.
6.2.2.2 Fire engineering calculations
Calculations may be generated and applied for the following.
a) Temperature profile
Heat transfer through walls where the insulation and/or thickness of the wall has been changed may
be calculated by using an accepted temperature analysis model that is appropriate to the form of
construction, e.g. studded composite construction. Input data should be based on values for specific
heat capacity and thermal conductivity as a function of temperature for all materials included in the
element. For composite elements, it is probably necessary to estimate, using relevant test results, the
duration of exposure at which destruction or detachment of parts of the element (i.e. facings, insulation,
etc.) will occur, as these will change the thermal exposure conditions.
b) Insulation performance
Compliance with the insulation criterion may be calculated using appropriate temperature profiles,
as above.
c) Deflection due to thermal gradient and its impact on loadbearing capacity
Deflections may be calculated for walls where the physical properties and the relationships between
stress and strain (including, if necessary, creep effect) are known as a function of temperature and
where the temperature profile over the cross-section of the partition is known. This is a complex
procedure for composite elements, both studded and SIPS.
6.2.2.3 Expert judgements
Changes may be made to the following construction parameters of the walls provided that expert
judgement, based upon the methodology given in Annex A, is adopted.
6.2.2.3.1 General param
...