ISO 22899-1:2021

INTERNATIONAL ISO
STANDARD 22899-1
Second edition
2021-06
Determination of the resistance to
jet fires of passive fire protection
materials —
Part 1:
General requirements
Détermination de la résistance aux feux propulsés des matériaux de
protection passive contre l'incendie —
Partie 1: Exigences générales
Reference number
©
ISO 2021
© ISO 2021
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ii © ISO 2021 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 3
5 Test configurations . 3
5.1 General . 3
5.2 Internal configuration . 4
5.3 External configuration . 5
6 Construction of the test items and substrates . 5
6.1 General . 5
6.2 Material . 5
6.3 Nozzle. 5
6.4 Flame re-circulation chamber. 6
6.5 Protective chamber . 7
6.6 Panel test specimens (internal configuration) . 9
6.7 Structural steelwork test specimens (internal configuration) .10
6.8 Tubular section test specimens (external configuration) .13
7 Passive fire protection systems .14
7.1 General .14
7.2 Panel test specimens .14
7.3 Structural steelwork test specimens .15
7.4 Tubular section test specimens .15
7.5 Assembly specimens .16
7.5.1 General.16
7.5.2 Requirements for assemblies mounted on panels . .16
7.5.3 Cable transit systems .17
7.6 Pipe penetration systems .18
8 Instrumentation .21
8.1 General .21
8.2 Panel test specimens .21
8.3 Structural steelwork test specimens .22
8.4 Tubular section test specimens .23
8.5 Assembly specimens .24
8.5.1 General.24
8.5.2 Panel mounted cable transit systems .24
8.5.3 Tubular section mounted assemblies .25
8.6 Recommended instrumentation of pipe penetration seals .26
9 Test apparatus and conditions .27
9.1 Nozzle geometry and position .27
9.1.1 General.27
9.1.2 Nozzle position for panel (including panel assemblies) and steelwork tests .27
9.1.3 Nozzle position for tubular section (including assemblies) tests .28
9.2 Fuel .29
9.3 Test environment .29
10 Test procedure .29
11 Repeatability and reproducibility .33
12 Uncertainty of measurement .33
13 Test report .33
14 Practical application of test results .35
14.1 General .35
14.2 Performance criteria .35
14.2.1 General.35
14.2.2 Coatings and spray-applied materials .35
14.2.3 Systems and assemblies .36
14.3 Factors affecting the validity of the test .36
14.3.1 General.36
14.3.2 Interruption of the jet fire .36
14.3.3 Failure of thermocouples . .36
14.3.4 Failure of the re-circulation chamber connection .37
Annex A (normative) Methods of fixing thermocouples .38
Annex B (informative) Example test report .40
Bibliography .43
iv © ISO 2021 – 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 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 2, Fire
containment.
This second edition cancels and replaces the first edition (ISO 22899-1:2007), which has been
technically revised. The main changes compared to the previous edition are as follows:
— Corrections to figures;
— Revision of the method of test for penetration seals.
A list of all parts in the ISO 22899 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.
Introduction
The test procedure described in this document enables the determination of properties of passive
fire protection materials. This test is designed to give an indication of how passive fire protection
materials are likely to perform in a jet fire. The dimensions of the test specimen can be smaller than
typical structure or plant items and the release of gas can be substantially less than that which can
occur in a credible event. However, individual thermal and mechanical loads imparted to the passive
fire protection material from the jet fire defined in this document have been shown to be similar to
those imparted from large-scale jet fires resulting from high-pressure releases of natural gas.
NOTE Guidance on the applicability of the test is intended to be covered in a future part of the ISO 22899
series.
Although the method specified in this document has been designed to simulate certain conditions
that occur in an actual jet fire, it cannot reproduce them all exactly and the thermal and mechanical
loads do not necessarily coincide. The results of this test do not guarantee safety but may be used as
elements of a fire risk assessment for structures or plants. This should also take into account all the
other factors that are pertinent to an assessment of the fire hazard for a particular end use. The test is
[3]
not intended to replace the hydrocarbon fire resistance test (ISO/TR 834-3/EN 1363-2 ) but is seen as
a complementary test.
Users of this document are advised to consider the desirability of third-party certification/inspection/
testing of product conformity with this document.
vi © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 22899-1:2021(E)
Determination of the resistance to jet fires of passive fire
protection materials —
Part 1:
General requirements
1 Scope
This document describes a method of determining the resistance to jet fires of passive fire protection
materials and systems. It gives an indication of how passive fire protection materials behave in a jet fire
and provides performance data under the specified conditions.
It does not include an assessment of other properties of the passive fire protection material such as
weathering, ageing, shock resistance, impact or explosion resistance, or smoke production.
Complete I-beams and columns cannot be tested to this document due to disruption of the characteristics
of the jet.
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 834-1:1999, Fire-resistance tests — Elements of building construction — Part 1: General requirements
ISO 13702, Petroleum and natural gas industries — Control and mitigation of fires and explosions on
offshore production installations — Requirements and guidelines
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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 https:// www .electropedia .org/
3.1
assembly
unit or structure composed of a combination of materials or products, or both
3.2
critical temperature
maximum temperature that the equipment, assembly (3.1) or structure to be protected may be allowed
to reach
3.3
Delta Tmax
maximum temperature rise (3.18) recorded by any of the installed thermocouples
3.4
fire barrier
separating element that resists the passage of flame and/or heat and/or effluents for a period of time
under specified conditions
3.5
fire resistance
ability of an item to fulfil, for a stated period of time, the required stability and/or integrity (3.8) and/
or thermal insulation and/or other expected duty, reaching the critical temperature (3.2) specified in a
standard fire-resistance test
3.6
fire test
procedure designed to measure or assess the performance of a material, product, structure or system
to one or more aspects of fire
3.7
flame re-circulation chamber
mild steel box, open at the front, into which the jet fire (3.10) is directed giving a re-circulating flame
resulting in a fireball
Note 1 to entry: Materials other than mild steel may be used when appropriate.
3.8
integrity
ability of a separating element, when exposed to fire on one side, to prevent the passage of flames and
hot gases or occurrence of flames on the unexposed side, for a stated period of time in a standard fire
resistance (3.5) test
3.9
intermediate-scale test
test performed on an item of medium dimensions
Note 1 to entry: A test performed on an item of which the maximum dimension is between 1 m and 3 m is usually
called an intermediate-scale test. This document describes an intermediate-scale jet fire test (3.6).
3.10
jet fire
ignited discharge of propane vapour under pressure
3.11
jet nozzle
orifice from which the flammable material issues
3.12
outside specimen diameter
specimen diameter measured to the outer surface of the passive fire protection (3.13) system on a
tubular specimen
3.13
passive fire protection
coating or cladding arrangement or free-standing system that, in the event of fire, provides thermal
protection to restrict the rate at which heat is transmitted to the object or area being protected
Note 1 to entry: The term "passive" is used to distinguish the systems tested, including those systems that react
chemically, e.g. intumescents, from active systems such as water deluge.
3.14
passive fire protection material
coating or cladding that, in the event of a fire, provides thermal protection to restrict the rate at which
heat is transmitted to the object or area being protected
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3.15
passive fire protection system
removable jacket or inspection panel, cable transit system, pipe penetration seal (3.16) or other such
system that, in the event of a fire, provides thermal protection to restrict the rate at which heat is
transmitted to the object or area being protected
3.16
penetration seal
system used to maintain the fire resistance (3.5) of a separating element at the position where there is
provision for services to pass through the separating element
3.17
protective chamber
mild steel box, open at the front and back, which is designed to be attached to the rear of the flame
re-circulation chamber (3.7) to shield the rear of the flame re-circulation chamber from environmental
influences
Note 1 to entry: A protective chamber is not required for tubular section tests but may be used to provide
additional stability to the flame re-circulation chamber.
3.18
temperature rise
increase in measured temperature above the initial temperature at a given location
4 Principle
The method presented in this document provides an indication of how passive fire protection materials
perform in a jet fire that can occur, for example, in petrochemical installations. It aims at simulating
[4]
the thermal and mechanical loads imparted to passive fire protection material by large-scale jet fires
resulting from high-pressure releases of flammable gas, pressure liquefied gas or flashing liquid fuels.
Jet fires give rise to high convective and radiative heat fluxes as well as high erosive forces. To generate
−1
both types of heat flux in sufficient quantity, a 0,3 kg s sonic release of gas is aimed into a shallow
chamber, producing a fireball with an extended tail. The flame thickness is thereby increased and hence
so is the heat radiated to the test specimen. Propane is used as the fuel since it has a greater propensity
to form soot than does natural gas and can therefore produce a flame of higher luminosity. High erosive
forces are generated by the release of the sonic velocity gas jet 1 m from specimen surface.
5 Test configurations
5.1 General
There are two basic configurations under which the test can be operated:
a) an internal configuration where one or more of the inner faces of the flame re-circulation chamber
incorporates the test construction;
b) an external configuration where the test construction is installed on supports in front of the flame
re-circulation chamber.
These two alternative configurations are shown in Figures 1 and 2.
Dimensions in millimetres
Key
1 protective chamber
2 jet nozzle
3 supports
a
Flame re-circulation chamber either with coated inner surfaces or with the rear face replaced by a panel to form
the test construction.
Figure 1 — Layout for internal configuration
Dimensions in millimetres
Key
1 flame re-circulation chamber
2 flame re-circulation chamber support
3 test construction
4 test construction support
5 jet nozzle
Figure 2 — Layout for external configuration
5.2 Internal configuration
The internal test configuration is used for determining the jet fire resistance of:
a) protection systems for plane surfaces;
b) protection systems for edge features;
c) fire barriers;
4 © ISO 2021 – All rights reserved

d) penetration systems used in conjunction with fire barriers.
5.3 External configuration
The external test configuration is used for determining the jet fire resistance of protected hollow
sections or assemblies mounted on hollow sections.
6 Construction of the test items and substrates
6.1 General
The key items required for the test are the jet release nozzle, the flame re-circulation chamber and a
protective chamber. These items are all required for the internal configurations of the test and the test
specimen forms all or part of the flame re-circulation chamber. In the external configurations of the
test, the flame re-circulation chamber is only used to help produce the fireball and it is not necessary to
use the protective chamber.
6.2 Material
The material normally used is 10 mm thick steel plate conforming to ISO 630-1:2011, Grade Fe 430. All-
welded construction shall be used and all welds shall be 5 mm fillet and continuous unless otherwise
stated. The use of substrates manufactured from other materials or thicknesses other than 10 mm shall
be documented in the report.
All dimensions are in millimetres and, unless otherwise stated, the following tolerances shall be used:
— whole number ±1,0 mm
— decimal to point ,0 ±0,4 mm
— decimal to point ,00 ±0,2 mm
— angles ±0’ 30”
— radii ±0,4 mm
6.3 Nozzle
The fuel is released towards the specimen from a nozzle. The tapered, converging nozzle shall be of
length 200 ± 1 mm, inlet diameter 52 ± 0,5 mm and outlet diameter 17,8 ± 0,2 mm. Figure 3 shows
the details of construction. The nozzle shall be constructed of heat resistant stainless steel. Provisions
shall be made for fitting a sighting device.
Dimensions in millimetres
Figure 3 — Nozzle
6.4 Flame re-circulation chamber
The side, top and bottom walls of the flame re-circulation chamber shall be constructed from mild
steel of 10 mm thickness. The rear wall of the chamber shall either be constructed of 10 mm thick steel
welded to the sides of the chamber or of a panel bolted on to form the rear wall. If the substrate material
is not steel or the substrate thickness is not 10 mm, the material and thickness used shall be stated in
the test report. The details of construction of the flame re-circulation chamber are given in Figure 5.
The flame re-circulation chamber, having nominal internal dimensions 1 500 mm × 1 500 mm ×
500 mm, shall be used for each test. The chamber is flanged at the rear to allow bolting on of a panel
when required and attachment, by bolting or clamping, of the protective chamber when required. A
general view of the flame re-circulation chamber is shown in Figure 4 and details of construction are
shown in Figure 5.
Dimensions in millimetres
Key
1 flame re-circulation chamber
a
Jet position.
Figure 4 — General view of flame re-circulation chamber
Details of the flange construction, apart from the hole spacing, are not given as one of two methods may
be used:
a) The flanges may be constructed by welding L-section steel to the rear of each wall.
b) For structural steelwork specimens, the rear wall may be constructed by continuously welding a
1 620 mm × 1 620 mm plate on to the rear of the flame re-circulation chamber and drilling holes at
the appropriate locations in the plate extending beyond the sides of the chamber.
Inner walls that do not form part of the specimen, e.g. the sidewalls in a panel test, shall be protected
from distortion by an alkaline earth silicate board or other suitable form of passive fire protection or
insulation material.
When testing in the external configuration, the recirculation chamber shall have a rear wall and the
recirculation chamber shall be insulated.
6 © ISO 2021 – All rights reserved

Dimensions in millimetres
Key
1 lifting lug, 25 mm thick machined steel
2 sixteen holes drilled, ∅ 18
Figure 5 — Construction of flame re-circulation chamber
6.5 Protective chamber
The protective chamber (nominal internal dimensions 1 500 mm × 1 500 mm × 1 000 mm) is used
to shield the rear of the flame re-circulation chamber from environmental influences in the internal
configuration of the test. It shall generally be constructed from mild steel of 10 mm thickness and
shall be open at the front and back and flanged at the front to allow fitting to the rear of the flame re-
circulation chamber with no visible air gaps.
A general view of the protective chamber is shown in Figure 6 and details of construction are shown in
Figure 7.
Figure 6 — General view of protective chamber
8 © ISO 2021 – All rights reserved

Dimensions in millimetres
Key
1 lifting lug, 25 mm thick machined steel
2 sixteen holes drilled, ∅ 18
Figure 7 — Construction of protective chamber
6.6 Panel test specimens (internal configuration)
The panel test specimen shall consist of a flame re-circulation chamber, with the rear wall replaced
by the panel to be tested. The panel is sandwiched between the flame re-circulation chamber and the
protective chamber as illustrated in Figure 8. The connection between the panel and the flame re-
circulation chamber shall be gas tight. The method of mounting depends on the type of passive fire
protection as described in 7.1.
Dimensions in millimetres
Key
1 flame re-circulation chamber
2 protective chamber
3 Panel
a
Jet position.
Figure 8 — Position of panel
For cases that simulate steelwork with no corners or edge features; or cylindrical vessels, pipes and
tubular sections of outside diameter greater than 500 mm, a 1 620 mm × 1 620 mm panel shall be
constructed from 10 mm thick steel. The details of construction are shown in Figure 9.
6.7 Structural steelwork test specimens (internal configuration)
The structural steelwork test specimen shall consist of the flame re-circulation chamber with the
addition of a 20 mm thick central web, 250 mm deep, to simulate corner or edge features such as
stiffening webs or edges of “I” beams. A general view of the test specimen is illustrated in Figure 10.
10 © ISO 2021 – All rights reserved

Dimensions in millimetres
Figure 9 — Construction of panels
Dimensions in millimetres
Key
1 flame re-circulation chamber
a
Jet position with web.
b
Simulated corner or edge feature of "I" beam.
Figure 10 — General view of structural steelwork test specimen
Details of the construction of a structural steelwork specimen are given in Figure 11. For a structural
steelwork test, the rear wall shall be constructed of 10 mm thick steel. The bottom flange may be
omitted if desired. The web shall comprise two 10 mm thick steel plates, which are slotted before being
welded together, to have thermocouples inserted and fixed in accordance with the methods given in
Annex A. Holes shall be drilled in the rear wall of the flame re-circulation chamber to match the slot
positions. Details of construction of the web are given in Figure 12. If the substrate material is not steel
or the steel thickness of the web and rear wall is different from 20 mm and 10 mm respectively, the
material and thickness used shall be stated in the test report.
When testing passive fire protection materials used to protect structural sections with substrates other
than steel or when the thickness of the corner or edge feature on the structural section is different from
20 mm, the central web and rear wall of the flame re-circulation chamber may be constructed from the
relevant substrate material and may be of the relevant thickness.
Dimensions in millimetres
Key
1 lifting lug, 25 mm thick machined steel
2 thirteen holes drilled, ∅ 18
3 six holes drilled and taped in bulkhead to match machined holes in central web; threads to be similar to
1/8 British Standard Pipe Thread
4 central web
Figure 11 — Construction of structural steelwork specimen
12 © ISO 2021 – All rights reserved

Dimensions in millimetres
Key
a
Groove machined 3,3 mm deep using 5,0 mm diameter ball nosed cutter.
b
Groove machined 3,0 mm deep using 5,0 mm diameter ball nosed cutter.
c
Weld preparation, four positions along this edge.
d
Weld preparation, full length along these edges.
e
Weld plates together after machining with a single V-butt weld; weld to be intermittent and ground flush.
f
Weld plates together after machining with a single continuous V-butt weld.
Figure 12 — Construction of web for structural steelwork specimen
6.8 Tubular section test specimens (external configuration)
The tubular section test specimen shall consist of a 3 000 mm long tubular section and shall be of the
following type depending on the outside diameter:
a) if the outside diameter, including the passive fire protection system, does not exceed 350 mm, the
full-scale tubular section shall be used; or
b) if the outside diameter, including the passive fire protection system, exceeds 350 mm, the diameter
of the tubular section shall be reduced so that the outside diameter is no more than 350 mm,
keeping the wall thickness of the tubular section as close as possible to that to be used in practice.
A general view of a tubular section specimen is given in Figure 13.
The material, diameter and wall thickness of the tubular section used shall be stated in the test report.
The tubular section shall be drilled with holes of sufficient diameter to allow thermocouples to be
passed down the inside of the tubular section. The access hole for each thermocouple shall be not more
than 50 mm longitudinally from the measuring position.
In some cases, e.g. an enclosure for a valve, the outside diameter may exceed 350 mm for a length not
exceeding 400 mm.
Dimensions in millimetres
Key
1 flame re-circulation chamber
2 tubular section specimen
a
Jet position.
Figure 13 — General view of tubular test
7 Passive fire protection systems
7.1 General
The passive fire protection systems are either coated or mounted onto the substrates described in
Clause 6.
7.2 Panel test specimens
When the passive fire protection material is in the form of a panel, the panel shall be fixed to act as the
rear wall of the flame re-circulation chamber as shown in Figure 8. The method of mounting shown in
Figure 14 depends on the type of passive fire protection and is detailed as follows.
a) For a rigid stand-alone panel, at least one joint shall be included in the panel and this shall be
positioned vertically, offset from the centre by 250 ± 50 mm. If the joint is not symmetrically
resistant to a jet fire flowing across the front of the rear wall of the flame re-circulation chamber,
e.g. a lap joint, the joint shall be oriented to give the most severe exposure to the jet fire as shown in
Figure 14.
The rigid panel may extend to the full 1 620 mm × 1 620 mm substrate dimensions as discussed in 6.5.
b) If the panel profile is not planar (e.g. trapezoidal), it can be necessary to incorporate a rigid
surround around the panel to achieve a gas-tight connection.
c) When the passive fire protection material is in the form of a flexible panel, it can be necessary to
incorporate a rigid surround (e.g. 50 mm box section steel) around the panel to achieve a gas-tight
connection as shown in Figure 14.
d) When the passive fire protection is in the form of a coating, the joint is omitted as shown in
Figure 14.
The connection between the panel and the flame re-circulation chamber shall be sealed to prevent
passage of hot gases, e.g. using soft mastic or fibre. In all cases, the side, top and bottom walls of the
14 © ISO 2021 – All rights reserved

flame re-circulation chamber shall be protected by an alkaline earth silicate board or other suitable
passive fire protection material.
Key
1 joint
2 face exposed to jet fire
3 flat rigid panel
4 profile rigid panel
5 box section surround
6 passive fire protection covering
7 passive fire protection coating
Figure 14 — Different types of panel PFP
7.3 Structural steelwork test specimens
For testing passive fire protection materials applied as coatings, the structural steelwork test specimen
shall have passive fire protection material applied directly to all inside surfaces of the specimen. The
outside surfaces of the sides, top and bottom of the specimen shall also be coated to a distance of at
least 50 mm from the front edge, including any reinforcement.
7.4 Tubular section test specimens
A minimum of 2 500 mm of the central part of the tubular section test specimen shall be covered by
the passive fire protection material under test. If the unprotected ends of the tubular section are not
protected by PFP they shall be protected by a suitable insulation material.
7.5 Assembly specimens
7.5.1 General
Assemblies can be mounted on a panel (internal configuration) or a hollow section (external
configuration). If an assembly is more than 400 mm in width or the geometry sufficiently complex
that the flame characteristics are clearly affected, a demonstration at full scale can be necessary, e.g. a
−1
3 kg s natural gas jet fire impinging on a full-scale specimen at 9 m from the release point.
For assemblies mounted on panels, the panel shall be fixed to act as the rear wall of the flame re-
circulation chamber as shown in Figure 8. The connection between the panel and the flame re-
circulation chamber shall be sealed to prevent passage of hot gases, e.g. using soft mastic or ceramic
fibre. The side, top and bottom walls of the flame re-circulation chamber shall be protected by an
alkaline earth silicate board or other suitable passive fire protection material.
7.5.2 Requirements for assemblies mounted on panels
Assemblies to be mounted in a division (e.g. cable transit systems or pipe penetration seals) should
be mounted through an aperture in a panel specimen made from the type of division to be used in
the intended application in accordance with 6.6. If the assembly cannot be tested full size without
affecting the key features of the test, then a reduced scale assembly can be used provided it reproduces
the key features of the intended application. The assembly shall be positioned no closer than 200 mm
from exposed edges of the panel. Where more than one assembly are to be tested simultaneously in
a panel, the separation between adjacent assemblies shall be 200 mm. If two assemblies are tested
simultaneously, they shall be placed symmetrically about either side of the vertical centreline of the
panel. The positioning of features that can affect the flow of the jet fire shall be at the discretion of the
test laboratory and any third-party certifying body. The position for a single panel mounted assembly
should be offset horizontally from the jet impingement point by 100 mm. When two assemblies are to
be tested simultaneously both assemblies shall be offset from the jet impingement point by 100 mm.
When the size or shape of assemblies prevent this from being achieved with the jet impingement point
at a height of 375 mm the nozzle may be raised to a maximum height of 600 mm. The distance from
the assemblies to the jet impingement point shall include any insulation which is part of the system.
The positions for a single panel mounted assembly and two panel mounted assemblies are given in
Figure 15.
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Dimensions in millimetres
Key
a
Jet position.
Figure 15 — Positions of panel mounted assemblies
7.5.3 Cable transit systems
A cable transit consists of a metal frame, box or coaming, sealant system or material and the cables,
and it may be uninsulated, partially insulated or fully insulated. The metal frame, box or coaming shall
be mounted into a panel representative of the fire barrier using the normal method. For example, the
frame, box, or coaming, which supports the cable transit system may be incorporated into a fire barrier
(typically 830 mm × 740 mm). The frame, box or coaming should be fitted such that it is flush with the
front surface of the fire barrier. The fire barrier is then welded into a hole cut into a support panel, e.g.
a firewall. This forms the back panel of the flame re-circulation chamber. The transit(s) shall be tested
incorporating a range of different types of cable (e.g. in terms of number and type of conductor, type
of sheathing, type of insulation material or size) and should provide an assembly which represents a
practical situation. No more than 40 % of the inside cross-sectional area of each transit shall be occupied
by cables and the distances between the cables and the inside of the transit shall be the minimum which
is allowable for the actual penetration sealing system. The cables shall project no more than 250 mm
beyond the panel on the exposed side of the panel and 500 mm on the unexposed side. The test results
obtained from a given configuration are generally valid for cables of size equal to or smaller than those
tested. Requirements for assemblies mounted on tubular sections:
For assemblies fixed to a tubular section, see 6.8.
a) If the assembly (e.g. soft jacket) is intended to protect a tubular section or vessel, a minimum of
2 500 mm and a maximum of 2 700 mm of the central part of the tubular section test specimen
shall be covered by the assembly under test.
b) If the assembly is a removable jacket, the fixing method shall be representative of the intended use
and joints/fitments shall be oriented to give the most severe exposure to the jet fire.
c) Assemblies to be mounted on a tubular section (e.g. removable jackets or valves) shall be mounted
on a tubular section specimen in accordance with 6.8. For assemblies, such as soft jackets, which
are applied uniformly, the maximum outer diameter (including the passive fire protection system)
shall be a maximum of 350 mm. Asymmetric assemblies, such as valve protection boxes, shall
normally be positioned in the centre of the tubular section. However, the positioning of features
that can affect the flow of the jet fire shall be at the discretion of the test laboratory and any third-
party certifying body. The maximum outside
...