ISO 5660-1:2002

Reaction-to-fire tests — Heat release, smoke production and mass loss rate — Part 1: Heat release rate (cone calorimeter method)

ISO 5660-1:2002 specifies a method for assessing the heat release rate of a specimen exposed in the horizontal orientation to controlled levels of irradiance with an external igniter. The heat release rate is determined by measurement of the oxygen consumption derived from the oxygen concentration and the flow rate in the combustion product stream. The time to ignition (sustained flaming) is also measured in this test.

Essais de réaction au feu — Débit calorifique, taux de dégagement de fumée et taux de perte de masse — Partie 1: Débit calorifique (méthode au calorimètre conique)

General Information

• Status: Withdrawn
• Publication Date: 05-Dec-2002
• Withdrawal Date: 05-Dec-2002
• ICS: 13.220.50 - Fire-resistance of building materials and elements
• Technical Committee: ISO/TC 92/SC 1 - Fire initiation and growth
• Drafting Committee: ISO/TC 92/SC 1/WG 5 - Small and bench scale fire test methods
• Current Stage: 9599 - Withdrawal of International Standard
• Completion Date: 20-Mar-2015

Relations

• Revised: ISO 5660-1:2015 - Reaction-to-fire tests — Heat release, smoke production and mass loss rate — Part 1: Heat release rate (cone calorimeter method) and smoke production rate (dynamic measurement)
• Effective Date: 25-Dec-2010
• Revises: ISO 5660-1:1993 - Fire tests — Reaction to fire — Part 1: Rate of heat release from building products — (Cone calorimeter method)
• Effective Date: 15-Apr-2008
• Revises: ISO 5660-1:1993/Cor 1:1993 - Fire tests — Reaction to fire — Part 1: Rate of heat release from building products — (Cone calorimeter method) — Technical Corrigendum 1
• Effective Date: 15-Apr-2008
• Revised: SIST ISO 5660-1:1995 - Fire tests -- Reaction to fire -- Part 1: Rate of heat release from building products -- (Cone calorimeter method)
• Effective Date: 12-May-2008

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 5660-1
Second edition
2002-12-15
Reaction-to-fire tests — Heat release,
smoke production and mass loss rate —
Part 1:
Heat release rate (cone calorimeter method)
Essais de réaction au feu — Débit calorifique, taux de dégagement de
fumée et taux de perte de masse —
Partie 1: Débit calorifique (méthode au calorimètre conique)

Reference number
ISO 5660-1:2002(E)
© ISO 2002

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ISO 5660-1:2002(E)
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ISO 5660-1:2002(E)
Contents Page
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 2
5 Principle . 3
6 Apparatus . 3
7 Suitability of a product for testing . 6
8 Specimen construction and preparation . 7
9 Test environment . 9
10 Calibration . 9
11 Test procedure . 12
12 Calculations . 14
13 Test report . 16
Annexes
A Commentary and guidance notes for operators. 24
B Resolution, precision and bias . 26
C Mass loss rate and effective heat of combustion . 31
D Testing in the vertical orientation. 32
E Calibration of the working heat flux meter. 35
F Calculation of heat release with additional gas analysis . 36
Bibliography. 39
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ISO 5660-1:2002(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO 5660 may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 5660-1 was prepared by Technical Committee ISO/TC 92, Fire safety, Subcommittee
SC 1, Fire initiation and growth.
This second edition cancels and replaces the first edition (ISO 5660-1:1993), which has been technically revised.
ISO 5660 consists of the following parts, under the general title Reaction-to-fire tests — Heat release, smoke
production and mass loss rate:
— Part 1: Heat release rate (cone calorimeter method)
— Part 2: Smoke production rate (dynamic measurement)
— Part 3: Guidance on heat and smoke release rate
Annexes A, B, C, D, E and F of this part of ISO 5660 are for information only.
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INTERNATIONAL STANDARD ISO 5660-1:2002(E)
Reaction-to-fire tests — Heat release, smoke production and mass
loss rate —
Part 1:
Heat release rate (cone calorimeter method)
1 Scope
This part of ISO 5660 specifies a method for assessing the heat release rate of a specimen exposed in the horizontal
orientation to controlled levels of irradiance with an external igniter. The heat release rate is determined by
measurement of the oxygen consumption derived from the oxygen concentration and the flow rate in the combustion
product stream. The time to ignition (sustained flaming) is also measured in this test.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 5660. For dated references, subsequent amendments to, or revisions of, any of these publications do
not apply. However, parties to agreements based on this part of ISO 5660 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated references,
the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of
currently valid International Standards.
ISO 554:1976, Standard atmospheres for conditioning and/or testing — Specifications
ISO 13943:2000, Fire safety — Vocabulary
ISO/TR 14697:1997, Fire tests — Guidance on the choice of substrates for building products
3 Terms and definitions
For the purposes of this part of ISO 5660, the terms and definitions given in ISO 13943 and the following apply.
3.1
essentially flat surface
surface whose irregularity from a plane does not exceed ±1mm
3.2
flashing
existence of flame on or over the surface of the specimen for periods of less than 1s
3.3
ignition
onset of sustained flaming as defined in 3.10
3.4
irradiance
〈at a point on a surface〉 quotient of the radiant flux incident on an infinitesimal element of surface containing the
point, and the area of that element
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ISO 5660-1:2002(E)
NOTE Convective heating is negligible in the horizontal specimen orientation. For this reason, the term “irradiance” is used
instead of “heat flux” throughout this part of ISO 5660 as it best indicates the essentially radiative mode of heat transfer.
3.5
material
single substance or uniformly dispersed mixture
EXAMPLE Metal, stone, timber, concrete, mineral fibre and polymers.
3.6
orientation
plane in which the exposed face of the specimen is located during testing, with either the vertical or horizontal face
upwards
3.7
oxygen consumption principle
proportional relationship between the mass of oxygen consumed during combustion and the heat released
3.8
product
material, composite or assembly about which information is required
3.9
specimen
representative piece of the product which is to be tested together with any substrate or treatment
NOTE For certain types of product, for example products that contain an air gap or joints, it may not be possible to prepare
specimens that are representative of the end-use conditions (see clause 7).
3.10
sustained flaming
existence of flame on or over the surface of the specimen for periods of over 10 s
3.11
transitory flaming
existence of flame on or over the surface of the specimen for periods of between 1 s and 10 s
4 Symbols
See Table 1.
Table 1 — Symbols and their designations
Symbol Designation Unit
2
Initially exposed surface area of the specimen m
A
s
1/2 1/2 1/2
Orifice flow meter calibration constant m · g · K
C
−1
Net heat of combustion kJ· g
∆h
c
−1
Effective net heat of combustion MJ· kg
∆h
c,eff
m Mass of the specimen g
Total mass loss g
∆m
m Mass of the specimen at the end of the test g
f
m Mass of the specimen at sustained flaming g
s
•
−2 −1
Average mass loss rate per unit area between 10 % and 90 % of mass loss g· m · s
m
A,10−90
g
m Mass of the specimen at 10 % of total mass loss
10
m Mass of the specimen at 90 % of total mass loss g
90
•
−1
Mass loss rate of specimen g· s
m
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ISO 5660-1:2002(E)
Table 1 — Symbols and their designations (continued)
Symbol Designation Unit
• −1
Mass flow rate in exhaust duct kg· s
m
e
Orifice meter pressure differential Pa
∆p
•
Heat release rate kW
q
•
−2
Heat release rate per unit area kW· m
q
A
•
−2
Maximum value of the heat release rate per unit area kW· m
q
A,max
•
−2
kW· m
Average heat release rate per unit area over the period starting at t and ending 180 s later
q ig
A,180
• −2
Average heat release rate per unit area over the period starting at t and ending 300 s later kW· m
q ig
A,300
−2
MJ· m
Q Total heat released per unit area during the entire test
A,tot
r Stoichiometric oxygen/fuel mass ratio 1
o
t Time s
t Delay time of the oxygen analyser s
d
t Time to ignition (onset of sustained flaming) s
ig
∆t Sampling time interval s
t Time at 10 % of total mass loss s
10
t Time at 90 % of total mass loss s
90
T Absolute temperature of gas at the orifice meter K
e
X Oxygen analyser reading, mole fraction of oxygen 1
O
2
0
X Initial value of oxygen analyser reading 1
O
2
1
X Oxygen analyser reading, before delay time correction 1
O
2
5 Principle
This test method is based on the observation that, generally, the net heat of combustion is proportional to the amount
3
of oxygen required for combustion. The relationship is that approximately 13,1× 10 kJ of heat are released per
kilogram of oxygen consumed. Specimens in the test are burned under ambient air conditions, while being subjected
2 2
to a predetermined external irradiance within the range of 0 kW/m to 100 kW/m and measurements are made of
oxygen concentrations and exhaust gas flow rates.
The test method is used to assess the contribution that the product under test can make to the rate of evolution of
heat during its involvement in fire. These properties are determined on small representative specimens.
6Apparatus
A schematic representation of the apparatus is given in Figure 1. The individual components are described in detail
in 6.1 to 6.5.
With minor modifications to the apparatus, specimens may be tested in the vertical orientation. Annex D gives
guidance on these modifications.
6.1 Cone-shaped radiant electrical heater
The active element of the heater shall consist of an electrical heater rod, capable of delivering 5 000 W at the
operating voltage, tightly wound into the shape of a truncated cone (see Figure 2). The heater shall be encased on
the outside with a double-wall stainless-steel cone, filled with a refractory fibre blanket of nominal thickness 13 mm
3
and nominal density 100 kg/m . The irradiance from the heater shall be maintained at a preset level by controlling the
average temperature of three thermocouples (type K stainless-steel sheathed thermocouples have proved suitable
but Inconel or other high-performance materials are also acceptable), symmetrically positioned and in contact with,
but not welded to, the heater element (see Figure 2). Either 3,0 mm outside diameter sheathed thermocouples with
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ISO 5660-1:2002(E)
exposed hot junction or 1,0 mm to 1,6 mm outside diameter sheathed thermocouples with unexposed hot junction
shall be used. The heater shall be capable of producing irradiance on the surface of the specimen of up to
2
100 kW/m . The irradiance shall be uniform within the central 50 mm× 50 mm area of the exposed specimen
surface, to within ±2%.
6.2 Radiation shield
The cone heater shall be provided with a removable radiation shield to protect the specimen from the irradiance prior
to the start of a test. The shield shall be made of non-combustible material, with a total thickness not exceeding
12 mm. The shield shall be one of the following, either
a) water-cooled and coated with a durable matt black finish of surface emissivity � = 0,95± 0,05, or
b) not water-cooled, which may be either metal with a reflective top surface or ceramic in order to minimize radiation
transfer.
The shield shall be equipped with a handle or other suitable means for quick insertion and removal. The cone heater
base plate shall be equipped with a mechanism for moving the shield into position.
6.3 Irradiance control
The irradiance control system shall be properly tuned so that it maintains the average temperature of the heater
◦
thermocouples during the calibration described in 10.1.2 at the preset level to within ± 10 C.
6.4 Weighing device
The weighing device shall have an accuracy of ± 0,1 g or better, measured according to the calibration procedure
described in 10.2.2. The weighing device shall be capable of measuring the mass of specimens of at least 500 g. The
weighing device shall have a 10 % to 90 % response time of 4 s or less, as determined according to the calibration
described in 10.1.3. The output of the weighing device shall not drift by more than 1g over a 30-min period, as
determined with the calibration described in 10.1.4.
6.5 Specimen holder
The specimen holder is shown in Figure 3. The specimen holder shall have the shape of a square pan with an
opening of (106± 1) mm×(106± 1) mm at the top, and a depth of (25± 1) mm. The holder shall be
constructed of stainless steel with a thickness of (2,4± 0,15) mm. It shall include a handle to facilitate insertion and
removal, and a mechanism to ensure central location of the specimen under the heater and proper alignment with
3
the weighing device. The bottom of the holder shall be lined with a layer of low density (nominal density 65 kg/m )
refractory fibre blanket with a thickness of at least 13 mm. The distance between the bottom surface of the cone
heater and the top of the specimen shall be adjusted to be (25± 1) mm, except for dimensionally unstable materials
(60± 1) mm
for which the distance shall be (see 7.5).
6.6 Retainer frame
The frame shall be constructed of stainless steel with a thickness of (1,9± 0,1) mm, in the shape of a box with an
inside dimension of each side (111± 1) mm and a height of (54± 1) mm. The opening for the specimen face shall
be (94,0± 0,5) mm square as shown in Figure 4. The retainer frame shall have an appropriate means to secure it
to the specimen holder with a specimen in position.
6.7 Exhaust gas system with flow measuring instrumentation
The exhaust gas system shall consist of a centrifugal exhaust fan rated for the operating temperatures, a hood, intake
and exhaust ducts for the fan, and an orifice plate flow meter (see Figure 5). The distance between the bottom of the
hood and the specimen surface shall be (210± 50) mm. The exhaust system shall be capable of developing flows
3
up to 0,024 m /s, under standard conditions of temperature and pressure. The recommended location of the fan is
indicated on Figure 5. As an alternative, it is acceptable to locate the fan further downstream and to have the
measuring orifice before the fan, provided that the requirements described in the remainder of this clause are
fulfilled.
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ISO 5660-1:2002(E)
A restrictive orifice with an internal diameter of (57± 3) mm shall be located between the hood and the duct to
promote mixing.
A ring sampler shall be located in the fan intake duct for gas sampling, (685± 15) mm from the hood (see Figure 5).
The ring sampler shall contain 12small holes with a diameter of (2,2± 0,1) mm, to average the stream
composition, with the holes facing away from the flow to avoid clogging with soot.
The temperature of the gas stream shall be measured using a 1,0 mm to 1,6 mm outside diameter sheathed-junction
thermocouple or a 3mm outside diameter exposed-junction thermocouple positioned in the exhaust stack on the
centreline and (100± 5) mm upstream from the measuring orifice plate.
The flow rate shall be determined by measuring the differential pressure across a sharp edge orifice [internal
diameter (57± 3) mm, thickness (1,6± 0,3) mm] in the exhaust stack, at least 350 mm downstream from the fan,
if the latter is located as shown on Figure 5. If the fan is located further downstream than indicated in Figure 5, it is
acceptable to locate the orifice plate between the ring sampler and the fan. However, in that case the length of the
straight duct section on both sides of the orifice plate shall be at least 350 mm.
6.8 Gas sampling apparatus
The gas sampling apparatus shall incorporate a pump, a filter to prevent entry of soot, a cold trap to remove most of
the moisture, a by-pass system set to divert all flow except that required for the gas analysers, a further moisture trap
and a trap for CO removal. A schematic view of an example of the gas sampling apparatus is shown in Figure 6.
2
Other arrangements which satisfy the requirements may be used. The transport delay time of the oxygen analyser,
t , shall be determined according to 10.1.5, and shall not exceed 60 s.
d
NOTE If an (optional) CO analyser is used, the equations to calculate the heat release rate can be different from those for the
2
standard case (see clause 12 and annex F).
6.9 Ignition circuit
External ignition is accomplished by a spark plug powered from a 10 kV transformer or spark igniter. The spark plug
shall have a gap of (3,0± 0,5) mm. The electrode length and location of the spark plug shall be such that the spark
gap is located (13± 2) mm above the centre of the specimen, except for dimensionally unstable materials for which
the distance shall be (48± 2) mm (see 7.5).
6.10 Ignition timer
The ignition timer shall be capable of recording elapsed time to the nearest second and shall be accurate to within
1s in 1h.
6.11 Oxygen analyser
The oxygen analyser shall be of the paramagnetic type, with a range of at least 0 % oxygen to 25 % oxygen. The
analyser shall exhibit a drift of not more than 50 parts per million of oxygen over a period of 30 min, and a noise of
not more than 50 parts per million of oxygen during this 30-min period, as measured according to 10.1.6. Since
oxygen analysers are sensitive to stream pressures, the stream pressure shall be regulated (upstream of the
analyser) to minimize flow fluctuations, and the readings from the analyser compensated with an absolute pressure
transducer to allow for atmospheric pressure variations. The analyser and the absolute pressure transducer shall be
◦
located in an isothermal environment. The temperature of the environment shall be maintained to within 2 C of a
◦ ◦
preset value between 30C7 and 0 C. The oxygen analyser shall have a 10 % to 90 % of full-scale response time
of less than 12 s, as measured according to 10.1.5.
6.12 Heat flux meters
The working heat flux meter shall be used to calibrate the heater (see 10.2.5). It shall be positioned at a location
equivalent to the centre of the specimen face during this calibration.
2
This heat flux meter shall be of the Schmidt-Boelter (thermopile) type with a design range of (100± 10) kW/m . The
target receiving the heat shall be flat, circular, of approximately 12,5 mm in diameter and coated with a durable matt
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ISO 5660-1:2002(E)
black finish of surface emissivity � = 0,95± 0,05. The target shall be water-cooled. A cooling temperature which
would cause condensation of water on the target surface of the heat flux meter shall not be used.
Radiation shall not pass through any window before reaching the target. The instrument shall be robust, simple to set
±3%
up and use, and stable in calibration. The instrument shall have an accuracy of within and a repeatability to
within .± 0,5 %
The calibration of the working heat flux meter shall be checked according to 10.3.1, by comparison with two
instruments of the same type as the working heat flux meter and of similar range held as reference standards and not
used for any other purpose (see annex E). One of the reference standards shall be fully calibrated at a standardizing
laboratory at yearly intervals.
6.13 Calibration burner
The calibration burner shall be constructed from tube with a square or circular orifice with an area of
2
(500± 100) mm covered with wire gauze through which the methane diffuses. The tube is packed with refractory
fibre to improve uniformity of flow. The calibration burner is suitably connected to a metered supply of methane of at
least 99,5 % purity. The accuracy of the flow meter shall be ±2% of the readout, corresponding to a heat release
rate of 5kW. The accuracy verification shall be performed according to 10.3.3.
6.14 Data collection and analysis system
The data collection and analysis system shall have facilities for recording the output from the oxygen analyser, the
orifice meter, the thermocouples and the weighing device. The data collection system shall have an accuracy
◦
corresponding to at least 50 parts per million of oxygen for the oxygen channel, 0,5 C for the temperature
measuring channels, 0,01 % of full-scale instrument output for all other instrument channels, and at least 0,1 % for
time. The system shall be capable of recording data every second. The system shall be capable of storing a minimum
of 720 data per parameter. The raw data recorded for each test shall be stored so that it can be recovered and used
to check the accuracy of the software.
6.15 Optional side screens
For operational or safety reasons, it is permitted to guard the heater and sample holder with side screens. However,
it shall be demonstrated that the presence of the screens does not affect the ignition time and heat release rate
measurements according to the procedure described in 10.1.7.
If the screens form an enclosure, attention is drawn to the fact that there is a possible explosion hazard when the
instrument is not operated under conditions prescribed by this part of ISO 5660, in particular for experiments in an
oxygen-enriched atmosphere. If an explosion hazard exists, proper precautions shall be taken to protect the operator,
e.g. by installing an explosion vent facing away from the operator.
7 Suitability of a product for testing
7.1 Surface characteristics
A product having one of the following properties is suitable for testing:
a) an essentially flat exposed surface;
b) a surface irregularity which is evenly distributed over the exposed surface provided that
1) at least 50 % of the surface of a representative 100 mm square area lies within a depth of 10 mm from a
plane taken across the highest points on the exposed surface, or
2) for surfaces containing cracks, fissures or holes not exceeding 8mm in width nor 10mm in depth, the total
area of such cracks, fissures or holes at the surface does not exceed 30 % of a representative 100 mm
square area of the exposed surface.
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ISO 5660-1:2002(E)
When an exposed surface does not meet the requirements of either 7.1 a) or 7.1 b), the product shall be tested in a
modified form complying as nearly as possible with the requirements given in 7.1. The test report shall state that the
product has been tested in a modified form, and clearly describe the modification.
7.2 Asymmetrical products
A product submitted for this test can have faces which differ or can contain laminations of different materials arranged
in a different order in relation to the two faces. If either of the faces can be exposed in use within a room, cavity or
void, then both faces shall be tested.
7.3 Materials of short burning time
For specimens of short burning time (3 min or less), the heat release rate measurements shall be taken at not more
than 2s intervals. For longer burning times, 5s intervals may be used.
7.4 Composite specimens
Composite specimens are suitable for testing, provided that they are prepared as specified in 8.3 and are exposed in
a manner typical of end use conditions.
7.5 Dimensionally unstable materials
Samples that intumesce or deform so that they contact the spark plug prior to ignition, or the underside of the cone
heater after ignition, shall be tested with the separation of 60 mm between the base plate of the cone heater and the
upper surface of the specimen. In this case the heater calibration (see 10.2.5) shall be performed with the heat flux
meter positioned 60 mm below the cone heater base plate. It must be stressed that the time to ignition measured with
this separation is not comparable to that measured with the separation of 25 mm.
Other dimensionally unstable products, for example products that warp or shrink during testing, shall be restrained
against excessive movement. This shall be accomplished with four tie wires, as described below. Metal wires of
(1,0± 0,1) mm diameter and at least 350 mm long shall be used. The sample shall be prepared in the standard way
as described in clause 8. A tie wire is then looped around the sample holder and retainer frame assembly, so that it
is parallel to and approximately 20 mm away from one of the four sides of the assembly. The ends of the wire are
twisted together such that the wire is pulled firmly against the retainer frame. Excess wire is trimmed from the twisted
section before testing. The three remaining wires shall be fitted around the specimen holder and retainer frame
assembly in a similar manner, parallel to the three remaining sides.
8 Specimen construction and preparation
8.1 Specimens
8.1.1 Unless otherwise specified, three specimens shall be tested at each level of irradiance selected and for each
different exposed surface.
0
8.1.2 The specimens shall be representative of the product and shall be square with sides measuring 100 mm.
−2
8.1.3 Products with a normal thickness of 50 mm or less shall be tested using their full thickness.
8.1.4 For products with a normal thickness of greater than 50 mm, the requisite specimens shall be obtained by
cutting away the unexposed face to reduce the thickness to 50 mm.
8.1.5 When cutting specimens from products with irregular surfaces, the highest point on the surface shall be
arranged to occur at the centre of the specimen.
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ISO 5660-1:2002(E)
8.1.6 Assemblies shall be tested as specified in 8.1.3 or 8.1.4 as appropriate. However, where thin materials or
composites are used in the fabrication of an assembly, the nature of any underlying construction can significantly
affect the ignition and burning characteristics of the exposed surface.
The influence of the underlying layers shall be
...