prEN 1366-15

Fire resistance tests for service installations - Part 15: 1-, 2-, 3- sided ducts

This Part of EN 1366 specifies a method for determining the fire resistance of horizontal 1-, 2- or 3-sided ventilation ducts and ducts whose fire resistance depends on the fire resistance performance of a ceiling or wall (where ducts are located in cavities enclosed by fire-resistant shafts or ceilings). The test examines the behaviour of ducts exposed to fire from the outside (duct A) and fire inside the duct (duct B). This Standard is used in conjunction with EN1363-1.
This test method does not take into consideration the effect of spalling or deflection of the adjoining floor/wall.
This test method is only applicable to ventilation ducts that have passed the test for the appropriate time period according to EN1366-1 (Duct A and B) in vertical and horizontal orientations.
The test specimens should not incorporate access panels, these are tested in accordance with EN1366-1.

Feuerwiderstandsprüfungen für Installationen - Teil 15: 1-, 2- oder 3-seitige Lüftungsleitungen

Essais de résistance au feu des installations techniques - Partie 15 - Conduits de ventilation à 1, 2 ou 3 côtés

Preizkusi požarne odpornosti za napeljave - 15. del: 1-, 2- in 3-stranski kanali

General Information

• Status: Not Published
• Publication Date: 27-May-2025
• ICS: 13.220.50 - Fire-resistance of building materials and elements
• ICS: 91.140.30 - Ventilation and air-conditioning systems
• Technical Committee: CEN/TC 127 - Fire safety in buildings
• Drafting Committee: CEN/TC 127/WG 2 - Services
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 22-Feb-2024
• Due Date: 03-Apr-2024
• Completion Date: 22-Feb-2024
• Directive: 305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Mandate: M/117 - Horizontal complement to the mandates to CEN/CENELEC concerning the execution of standardization work for the valuation of construction products and elements in respect of their resistance to fire
• Ref Project: oSIST prEN 1366-15:2024 - Fire resistance tests for service installations - Part 15: 1-, 2-, 3- sided ducts

Overview

The prEN 1366-15:2023 standard, developed by CEN, outlines a critical methodology for assessing the fire resistance of horizontal 1-, 2-, or 3-sided ventilation ducts. These ducts form an integral part of building service installations. This part of EN 1366 focuses on testing ventilation ducts installed in cavities enclosed by fire-resistant shafts or ceilings, ensuring that they effectively prevent fire spread from one compartment to another.

The standard requires evaluation of fire exposure from both outside and inside the duct, referred to as duct A (fire on the outside) and duct B (fire within the duct). It complements the requirements specified in EN 1363-1, which governs general fire resistance test conditions. Notably, prEN 1366-15 excludes the effects of spalling or deflection of adjacent floors or walls from the test consideration.

Key Topics

• Test Scope: The procedure applies exclusively to horizontal ducts with 1-, 2-, or 3-sided construction, including ducts whose fire resistance depends on ceiling or wall performance.
• Application Limits: Only ducts that have already passed EN 1366-1 fire resistance tests are eligible for testing under this standard.
• Fire Exposure Types:
  • Fire outside the duct (duct A) with a maintained pressure differential.
  • Fire inside the duct (duct B) with air velocity conditions simulating operational scenarios.
• Test Specimens:
  • Must not include access panels (tested separately under EN 1366-1).
  • Sizes must meet prescribed minimum lengths and cross-section dimensions.
• Test Equipment:
  • Specialized furnaces simulating fire exposure in horizontal orientation.
  • Fans to maintain airflow and pressure within ducts during testing.
  • Measurement instruments for gas temperature, air velocity, and pressure differentials.
• Performance Criteria: Evaluation includes maintaining duct integrity and functionality under fire conditions for the designated time period.
• Safety Considerations: The standard highlights hazards associated with fire testing, such as toxic gas emission, necessitating rigorous safety protocols and training.

Applications

This standard is essential for:

• Building Designers and Engineers: Ensuring HVAC ductwork complies with fire compartmentation requirements to reduce fire propagation risks.
• Fire Safety Assessors: Evaluating fire resistance characteristics of ventilation ducts in compliance with European regulations.
• Manufacturers of Fire-Resistant Ducts: Validating product performance according to harmonized European test methods.
• Construction and Installation Professionals: Employing ducts that meet standardized fire ratings to guarantee safe building environments.

Typical practical applications include ventilation systems in commercial buildings, industrial facilities, hospitals, and residential complexes where fire compartmentation and smoke control are critical. The standard provides a reliable test method to certify that ventilation ducts can withstand fire endurance requirements, helping to protect occupants and assets.

Related Standards

prEN 1366-15 serves as a complementary part of the EN 1366 series of standards dedicated to fire resistance testing of building service installations. Notable related standards include:

• EN 1363-1: General requirements for fire resistance tests.
• EN 1366-1: Fire resistance tests for ventilation ducts, focusing on vertical and horizontal ducts, including access panels.
• EN 1366-8: Specific tests for smoke extraction ducts.
• EN 1507 & EN 12237: Standards specifying strength and leakage requirements for sheet metal ducts.
• EN ISO 13943: Fire safety vocabulary aiding consistent terminology.
• EN 1366-5, EN 1366-7, EN 1366-10, EN 1366-11, EN 1366-13, EN 1366-14: Other parts addressing fire dampers, penetration seals, smoke control dampers, cable systems fire protection, and chimney fire resistance.

Adherence to prEN 1366-15 along with these harmonized standards helps ensure a comprehensive approach to fire safety in ventilation installations, promoting safer building design and regulatory compliance across Europe.

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Keywords: prEN 1366-15, fire resistance test, 1-sided ducts, 2-sided ducts, 3-sided ducts, fire-resistant ventilation ducts, horizontal ducts, CEN fire safety standards, EN 1366 series, ventilation duct fire testing, fire compartmentation, smoke control ducts, European fire resistance standards, HVAC fire safety.

Standards Content (Sample)

SLOVENSKI STANDARD
01-februar-2024
Preizkusi požarne odpornosti za napeljave - 15. del: 1-, 2- in 3-stranski kanali
Fire resistance tests for service installations - Part 15: 1-, 2-, 3- sided ducts
Feuerwiderstandsprüfungen für Installationen - Teil 15: 1-, 2- oder 3-seitige
Lüftungsleitungen
Essais de résistance au feu des installations techniques - Partie 15 - Conduits de
ventilation à 1, 2 ou 3 côtés
Ta slovenski standard je istoveten z: prEN 1366-15
ICS:
13.220.50 Požarna odpornost Fire-resistance of building
gradbenih materialov in materials and elements
elementov
91.060.40 Dimniki, jaški, kanali Chimneys, shafts, ducts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2023
ICS
English Version
installations - Part 15: 1-, 2-, 3- sided ducts'
Feuerwiderstandsprüfungen für Installationen - Teil
15: 1-, 2-, 3-seitige Leitungen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 127.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 1366-15:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Test equipment . 7
5 Test conditions . 8
6 Test specimen . 8
7 Installation of test specimen . 10
8 Conditioning . 11
9 Application of instrumentation . 12
10 Test procedure . 13
11 Performance criteria . 15
12 Test report . 15
13 Field of direct application of test results . 16
Annex A (informative) General Guidance . 31
A.1 General. 31
A.2 Notes on apparatus . 31
A.3 Notes on test specimens . 31
A.4 Notes on test conditions . 32
A.5 Notes on procedure . 33
A.6 Notes on performance criteria . 33
Bibliography . 34

European foreword
This document (prEN 1366-15:2023) has been prepared by Technical Committee CEN/TC 127 “Fire
safety in buildings”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
EN 1366 “Fire resistance tests for service installations” consists of the following:
— Part 1: Ventilation Ducts
— Part 2: Fire dampers
— Part 3: Penetration seals
— Part 4: Linear joint seals
— Part 5: Service ducts and shafts
— Part 6: Raised floors
— Part 7: Closures for conveyors and trackbound transportation systems
— Part 8: Smoke extraction ducts
— Part 9: Single compartment smoke extraction ducts
— Part 10: Smoke control dampers
— Part 11: Fire protective systems for cable systems and associated components Part 12: Non-
mechanical fire barrier for ventilation ductwork
— Part 13: Chimneys
— Part 14: Partial penetration seals
— Part 15: 1-,2- or 3-sided ventilation ducts
Introduction
The purpose of this test is to measure the ability of a representative 1 – 2 and 3 sided ventilation duct
assembly / system that is part of an air distribution system to resist the spread of fire from one fire
compartment to another with fire attack from inside or outside the duct. It is applicable to vertical and
horizontal ducts, with or without branches, taking into account joints and openings, as well as suspension
devices and penetration points.
The test measures the length of time for which ducts, of specified dimensions, suspended as they would
be in practice, satisfy defined criteria when exposed to fire from inside and outside the duct (separate
tests).
The test takes into account the effect of fire exposure from the outside where a pressure differential is
maintained in the duct as well as the effect of fire entering the ducts in conditions where forced air
movement may or may not be present.
Caution
The attention of all persons concerned with managing and carrying out this fire resistance test is drawn
to the fact that fire testing may be hazardous and that there is a possibility that toxic and/or harmful
smoke and gases may be evolved during the test. Mechanical and operational hazards may also arise
during the construction of the test elements or structures, their testing and disposal of test residues.
An assessment of all potential hazards and risks to health shall be made and safety precautions shall be
identified and provided. Written safety instructions shall be issued. Appropriate training shall be given
to relevant personnel. Laboratory personnel shall ensure that they follow written safety instructions at
all times.
1 Scope
This part of EN 1366 specifies a method for determining the fire resistance of horizontal 1-, 2- or 3-sided
ventilation ducts and ducts whose fire resistance depends on the fire resistance performance of a ceiling
or wall (where ducts are located in cavities enclosed by fire-resistant shafts or ceilings). The test
examines the behaviour of ducts exposed to fire from the outside (duct A) and fire inside the duct (duct
B). This document is used in conjunction with EN 1363-1.
This test method does not take into consideration the effect of spalling or deflection of the adjoining
floor/wall.
This test method is only applicable to ventilation ducts that have passed the test for the appropriate time
period according to EN 1366-1 (Duct A and B) in vertical and horizontal orientations.
Access panels as part of the duct, if any, are part of the test in accordance with EN 1366-1.
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.
EN 1363-1, Fire resistance tests - Part 1: General requirements
EN 1366-8, Fire resistance tests for service installations - Part 8: Smoke extraction ducts
EN 1507, Ventilation for buildings - Sheet metal air ducts with rectangular section - Requirements for
strength and leakage
EN 12237, Ventilation for buildings - Ductwork - Strength and leakage of circular sheet metal ducts
EN 20898-1, Mechanical Properties of fasteners – Part 1: Bolts, screws and studs (ISO 898)
EN 60584-1, Thermocouples - Part 1: EMF specifications and tolerances
EN ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in circular
cross-section conduits running full - Part 1: General principles and requirements (ISO 5167-1)
EN ISO 13943, Fire safety - Vocabulary (ISO 13943)
ISO 5221, Air distribution and air diffusion - Rules to methods of measuring air flow rate in an air-handling
duct
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply / the terms and definitions
given in EN 1363-1 and EN ISO 13943 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
fire-resistant ventilation duct
duct used for the distribution or extraction of air and designed to provide a degree of fire resistance
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.1]
3.2
combustible lining
lining / coating on the inner surface of the duct ; reaction to fire classification of the lining material (tested
in end use condition, treated as an external, non-substantial component) worse than class A2-s1,d0
according to EN 13501-1
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.2]
3.3
self-supporting duct
duct constructed e.g. from fire-protective boards without encasing a steel duct
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.3]
3.4
encased duct
4 sided or circular inner duct with 1-, 2- or 3-sided fire protective enclosure to provide fire resistance
3.5
unencased duct
1-, 2- or 3-sided duct where the fire protection itself is the air leading surface of the duct
3.6
suspension devices
components used for suspending and fixing a duct from a floor or supporting a duct from a wall
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.4]
3.7
adjoining wall
wall on the exposed side that the duct is build up against
3.8
adjoining floor
floor on the exposed side that the duct is build up against
3.9
compensator
device used to prevent damage from the forces generated by expansion
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.6]
3.10
access panel
cover for an inspection opening within the duct
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.7]
Note 1 to entry: The test specimens used here shall not incorporate access panels, these are tested in accordance
with EN1366-1.
3.11
kitchen extract duct
ductwork where combustible deposits, such as grease are likely to accumulate on its internal surfaces
[SOURCE: EN 1366-1:2014+A1 :2020, definition 3.9]
4 Test equipment
4.1 General
In addition to the test equipment specified in EN 1363-1 the following is required.
4.2 Furnace
This shall be capable of subjecting ventilation ducts to the standard heating and pressure conditions
specified in EN 1363-1 and be suitable for testing ducts in the horizontal (see Figure 1 to 4) orientation.
4.3 Fan for duct A
The fan shall be able to produce at the start and throughout the test an under-pressure of (300 ± 15) Pa
within duct A (see Figure 1-2) and shall be connected either directly, or by a suitable length of flexible
ducting, to the measuring station described in 4.5.
If the duct is used in practice as a smoke extraction duct, the duct shall be tested in accordance with
EN 1366-8. In this case, fan A shall be adjusted to (500 ± 15) Pa for testing duct according to this standard.
4.4 Fan for duct B
This shall be able to produce an air velocity when extracting gas from duct B (see Figure 3-4), of at least
3 m/s measured at ambient temperature in the duct before the test. It shall be connected either directly,
or by a suitable length of flexible ducting, to the air velocity measuring station described in 4.8. The fan
shall be provided with a by-pass vent that can be opened prior to the damper described in 4.7 being shut.
4.5 Volume flow rate measuring station
This shall consist of a venturi, orifice plate, or other suitable device and (where necessary) an airflow
straightener, installed in straight lengths of pipe, all sized to EN ISO 5167-1 and ISO 5221. It shall be
connected to the end of the condensing unit to determine the volume flow rate of gas passing through
duct A during the test. The measuring device shall be capable of measuring to an accuracy of ± 5 %.
Regardless of whether vertical or horizontal ducts are being tested, the volume flow measuring station
shall always be used in a horizontal orientation.
4.6 Condensing unit
This shall be installed between the end of duct A and the flow-measuring device and shall allow for
sufficient drainage. The gas temperature adjacent to the flow-measuring device shall be measured by
sheathed thermocouple, type K according EN 60584-1, max. 2 mm in diameter, with an insulated hot
junction, arranged pointing upwards to allow for draining moisture. Its measuring junction shall be
located at the centre line of the measuring tube and at a distance equal to twice the diameter of the
measuring tube downstream from the flow-measuring device. The temperature measured by this
thermocouple shall not exceed 40 °C.
4.7 Damper
This shall be installed between the fan and the air velocity measuring station to shut off the airflow in
duct B during evaluation of integrity in the “fan-off” condition.
4.8 Air velocity measuring station
This shall determine air velocity in duct B and shall consist of one or two inlet nozzle(s), or other suitable
device, installed in a straight length of pipe sized to EN ISO 5167-1 and ISO 5221, connected to the end of
both the vertical and horizontal duct B outside the furnace. The temperature of the extracted hot gas shall
be measured with a sheathed thermocouple type K according EN 60584-1, max. 2 mm in diameter, with
an insulated hot junction, arranged pointing upwards to allow for draining moisture. Its measuring
junction shall be located at the centre line of the pipe and at a maximum distance of 100 mm downstream
from the flange. If larger distance is necessary, the pipe between flange and measuring point shall be
insulated.
4.9 Equipment for measuring gas pressure
This shall be provided in the laboratory, in the furnace and inside duct A. The measuring equipment for
measuring pressures differentials between duct A and the laboratory must be provided with an accuracy
of ± 5 % relative to the intended pressure difference, i.e. ΔP = 300 or ΔP = 500 Pa.
5 Test conditions
The heating conditions and the furnace atmosphere shall conform to those given in EN 1363-1.
The furnace pressure shall be controlled to ΔP = 15 Pa throughout the test at the mid-height position of
the horizontal ducts.
Details of test conditions within the ducts during the test are given in Clause 10.
6 Test specimen
6.1 Size
6.1.1 General
For duct specimens of sizes other than those given in Table 2, the field of direct application is restricted
(see Clause 13).
6.1.2 Length
The minimum lengths of the parts of the test specimen inside and outside the furnace shall be as given in
Table 1 (see also Figures 1 to 4):
Table 1 – Minimum length of test specimen
Minimum length
(m)
Orientation
Inside Outside
furnace furnace
Horizontal 3,8 1,0
6.1.3 Cross section
The standard sizes of ducts given in Table 2 shall be tested unless only cross-sections smaller than the
standard size are used:
Table 2 – Internal cross-section of test specimen (dimension of the open cross-section)
Encased / Unencased Encased
Rectangular Circular
Duct
Height Diameter
Width (mm)
(mm) (mm)
A 1 000 ± 10 500 ± 10 800 ± 10
B 1 000 ± 10 250 ± 10 630 ± 10
Larger cross-sections are not covered by this standard.
6.2 Number of tests
Only horizontal ducts shall be tested according to this standard. The scenarios with vertical ducts are
covered by the vertical tests conducted according to EN1366-1.
Fire from outside scenario (duct A)
The fire from outside scenario (duct A) has to be tested as, shown on Figure no. 1 to 2
Fire from inside scenario (duct B)
The fire from inside scenario (duct B) has to be tested as, as shown on Figure no. 3 to 4
NOTE For the field of application regarding the penetration and standard supporting construction the same
rules of EN 1366-1 apply.
One test specimen shall be tested for each type of installation to be evaluated.
6.3 Design
6.3.1 General
The test shall be made on a test specimen representative of the complete duct assembly on which
information is required. The method of duct construction, support and penetration shall be
representative of that used in practice.
Ducts shall be arranged as shown in Figures 1 to 4.
6.3.2 Minimum distance between the ducts and between ducts and furnace walls
There is no limit to the number of ducts that may be tested simultaneously in the same furnace, provided
that there is sufficient space to do so, in accordance with the dimensions shown in Figures 1 to 4.
A minimum clear spacing of 500 mm shall be provided between the underside of a horizontal duct and
the furnace bottom floor. Similarly, there shall be a minimum clear spacing of at least 500 mm between
any adjacent ducts or furnace wall that are not part of the adjoining wall.
6.3.3 Configuration of duct A (horizontal only)
The horizontal duct A shall not include any branch on exposed side as prescribed in EN 1366-1.
6.3.4 Openings in duct B
For duct B, tested in a 2-sided solution one opening shall be provided in the exposed vertical side of the
duct inside the furnace. The opening shall be positioned (500 ± 25) mm from the end of the duct inside
the furnace (see Figure 3 and 4).
The clear openings shall have the same width/height ratio as the cross-section of the duct. For circular
ducts, the openings shall be rectangular with a width/height ratio of 4:1.
The total area of the opening shall be (35 ± 10) % of the internal cross-sectional area of the duct.
Framing of the openings shall be as in practise (to avoid weakening the duct walls in the area around the
openings).
6.3.5 Access panel
Access panels are tested in EN 1366-1.
6.3.6 Joints in horizontal ducts
The test configuration shall include at least one joint inside the furnace.
There shall be at least one joint in every layer of fire protection material (if applicable), inside the furnace
and in any steel duct.
The joints in fire protection material are not evaluated on the unexposed side. This is considered in
EN1366-1.
6.3.7 Compensator
Compensators can be incorporated on the exposed side of the test specimen for both duct A and B, if the
compensator was also included in the EN 1366-1 tests.
The position of the compensators should be as in the EN1366-1 tests.
6.3.8 Steel ducts
Where steel ducts are used, the sponsor of the test shall provide the laboratory with evidence of the
leakage class in accordance with EN 1507 or EN 12237.
6.3.9 Hangers
When protected hangers are used for the test, they must be insulated over their complete length.
7 Installation of test specimen
7.1 General
The test specimen shall be installed, as far as possible, in a manner representative of its use in practice.
The supporting construction selected shall be a wall, partition and/or floor either selected from the
standard supporting constructions in chapter 7.2 or of the type to be used in practice which shall have a
classified fire resistance equal or greater than the intended fire resistance of the duct being tested.
Rigid supporting construction shall be at least 200 mm and flexible supporting constructions 500 mm
from the exposed sides of the duct.
7.2 Standard supporting construction
Where the type of supporting construction to be used in practice is not known then one of the standard
supporting constructions described in EN 1366-1 shall be used.
A standard flexible wall construction shall be selected from the specifications as described in detail in
EN 1363-1.
7.3 Non-standard supporting construction
When the test specimen is intended to be used in a form of construction not covered by the standard
supporting constructions, it shall be tested in the supporting construction in which it is intended to be
used.
No forced deformation shall be applied to the non-standard supporting construction, and no additional
stiffening may be applied ex. fixing steel profiles on the unexposed side.
7.4 Fire stopping
The fire stopping of the penetration through the supporting construction shall be as intended in practice.
The maximum width of the gap between the duct and the wall shall be accommodated as used in practice.
7.5 Restraint of ducts
7.5.1 Inside furnace
All ducts shall be fully restrained in all directions at the furnace wall or floor remote from the penetration
point. Where there is the possibility of the furnace wall moving then the fixings shall be made
independently of the furnace structure.
7.5.2 Outside furnace
Both the fire from inside and fire from outside (Duct A and B) should be unrestrained on the unexposed
side.
8 Conditioning
8.1 General
Conditioning of the test construction shall be in accordance with EN 1363-1.
8.2 Water based sealing materials
Water-based materials (e.g. mortar, concrete …) used to seal the gap between the supporting construction
and the duct where the gap is ≤ 25 mm wide shall be conditioned for at least seven days before fire
testing.
Water-based materials used to seal the gap between the supporting construction and the duct assembly
where the gap is > 25 mm wide shall be conditioned for at least 28 days before fire testing.
9 Application of instrumentation
9.1 Thermocouples
9.1.1 Furnace thermocouples (plate thermometers)
Plate thermometers shall be provided in accordance with EN 1363-1 and shall be positioned as shown in
Figure 5.
For all ducts, the plate thermometers shall be oriented so that side ‘A’ faces the walls of the furnace
opposite the ducts being evaluated.
9.1.2 Unexposed surface thermocouples
9.1.2.1 General
The temperature of the test specimens shall be measured with thermocouples as described in EN 1363-1.
The position of thermocouples (for measuring maximum temperature, T1 and Ts) at the point of
penetration of the duct through the wall or floor is shown in Figures 6 to 7 and 9. At least one
thermocouple (Ti) of each type shall be positioned on each side of a rectangular duct – circular ducts shall
be measured analogously.
Thermocouples shall be located where a discontinuity in thickness of insulation or wall thickness of the
duct occurs. This includes additional fillets, strips etc.
No thermocouples for measuring the average temperature rise on the outer surface of the fire protection
(T2) is needed. Nor shall the maximum temperature rise on the outer surface of the fire protection
material coinciding with insulation and duct joints be measured. These evaluations are covered by
EN 1366-1.
9.1.2.2 Kitchen extract ducts and ducts with combustible lining
Where ducts with combustible internal linings are used, four additional thermocouples, reference T ,
shall be fixed inside duct A, at a position of approximately mid-span within the part of the duct exposed
within the furnace. The thermocouples shall be fixed to the inside face of the duct at the locations shown
in Figure 8. The thermocouples shall not coincide with joints or cover strips.
For kitchen extract ducts or where combustible internal combustible linings are used, four additional
thermocouples, reference T , shall be fixed inside duct A, at a position of approximately mid-span within
the part of the duct exposed within the furnace. The thermocouples shall be fixed to the inside face of the
duct at the locations shown in Figure 8. The thermocouples shall not coincide with joints or cover strips.
9.1.2.3 Suspension device
Where steel suspension devices are protected, then their temperatures shall be measured. A
thermocouple shall be positioned on each component of at least two suspension device systems (see
13.5.2)
9.2 Pressure
Furnace pressure shall be measured in accordance with chapter 5.
10 Test procedure
10.1 General
Before the test the leakage of the laboratory measuring and condensing system shall be measured, and
the system leakage shall be deducted from the total measuring leakage throughout the test.
The test shall be carried out using the equipment and procedures in accordance with EN 1363-1.
10.2 Control of conditions to permit assessment of integrity
10.2.1 Duct A
Control the under-pressure inside duct A (see Figure 10) to (300 ± 15) Pa (or (500 ± 15) Pa if required
by the test sponsor) below the laboratory pressure at the beginning of the test and maintain it at this
value throughout the test.
10.2.2 Duct B
Prior to the start of the test stabilize the air velocity in duct B (see Figure 11) to 3 m/s. Adjust the fan
during the “fan on” parts of the test to maintain the velocity of (3 ± 0,45) m/s. If the air temperature in
the duct is used in the calculation of the velocity, the temperature measured after the duct (Figure 11,
item 7) shall be used for the calculation. The temperature measurement shall be taken no further than
100 mm from the
...