IEC 61482-1-2:2014

IEC 61482-1-2 ®
Edition 2.0 2014-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Live working – Protective clothing against the thermal hazards of an electric
arc –
Part 1-2: Test methods – Method 2: Determination of arc protection class of
material and clothing by using a constrained and directed arc (box test)

Travaux sous tension – Vêtements de protection contre les dangers thermiques
d'un arc électrique –
Partie 1-2: Méthodes d’essai – Méthode 2: Détermination de la classe de
protection contre l’arc de matériaux et de vêtements au moyen d’un arc dirigé
et contraint (enceinte d'essai)

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IEC 61482-1-2 ®
Edition 2.0 2014-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Live working – Protective clothing against the thermal hazards of an electric

arc –
Part 1-2: Test methods – Method 2: Determination of arc protection class of

material and clothing by using a constrained and directed arc (box test)

Travaux sous tension – Vêtements de protection contre les dangers thermiques

d'un arc électrique –
Partie 1-2: Méthodes d’essai – Méthode 2: Détermination de la classe de

protection contre l’arc de matériaux et de vêtements au moyen d’un arc dirigé

et contraint (enceinte d'essai)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX U
ICS 13.220.40, 29.260, 29.260.99 ISBN 978-2-8322-1881-5

– 2 – IEC 61482-1-2:2014 © IEC 2014

CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and symbols. 6
3.1 Terms and definitions . 6
3.2 Symbols and units used in this document . 11
4 Principle of the test method . 11
4.1 Material box test procedure . 11
4.2 Garment box test procedure . 11
5 Significance and use of the test method . 12
6 Test apparatus . 12
6.1 Test apparatus and test box . 12
6.2 Material box test procedure . 15
6.2.1 Arrangement of the material box test procedure . 15
6.2.2 Test plate (panel) construction . 16
6.2.3 Sensor construction . 17
6.2.4 Sensor response . 17
6.3 Garment box test procedure . 17
6.3.1 Arrangement of the garment box test procedure . 17
6.3.2 Mannequin construction . 17
6.4 Electric supply and electrodes . 18
6.4.1 Test circuit . 18
6.4.2 Test circuit control . 18
6.4.3 Electrodes . 18
6.4.4 Fuse wire . 18
6.5 Electric test arc characteristics . 19
6.6 Measurement and data acquisition system . 19
7 Operator safety . 19
8 Specimen preparation . 20
8.1 Description of the test specimens . 20
8.1.1 Test specimens for material box test procedure . 20
8.1.2 Test specimens for garment box test procedure . 20
8.2 Pre-treatment by cleaning . 20
8.3 Pre-conditioning of the test specimens . 20
9 Calibration . 20
9.1 Data acquisition system pre-calibration . 20
9.2 Calorimeter calibration check . 20
9.3 Arc exposure calibration . 21
9.4 Calibration of the electric test circuit and testing . 21
9.5 Confirmation of test apparatus setting . 22
9.6 Preparing and conditioning of the box . 22
10 Apparatus care and maintenance . 22
10.1 Surface reconditioning of the sensors . 22
10.2 Care of test plate and mannequin . 23
10.3 Care of electrodes . 23

11 Test procedures . 23
11.1 Test parameters . 23
11.2 Number of tests . 23
11.3 Test conditions and initial temperature . 24
11.4 Specimen mounting . 24
11.4.1 Material box test procedure . 24
11.4.2 Garment box test procedure . 24
11.5 Specimen description . 24
12 Interpretation of results . 25
12.1 Heat transfer . 25
12.1.1 Determining time zero . 25
12.1.2 Plotting sensor response . 25
12.1.3 Incident energy E . 25
i
12.1.4 Sensor response versus Stoll curve . 25
12.2 Visual inspection . 25
12.3 Test result. 26
12.3.1 Acceptance criteria of material box test procedure . 26
12.3.2 Acceptance criteria of garment box test procedure . 26
13 Test report . 27
Annex A (informative) Precision of the test method . 28
Bibliography . 29

Figure 1 – Test box . 14
Figure 2 – Test set-up . 15
Figure 3 – Test plate with sensors (calorimeters in mounting boards) . 16

Table 1 – Test validity check range of direct exposure incident energy (permissible
direct exposure incident energy range) . 21
Table 2 – Test validity check range of arc energy (permissible arc energy range) . 22
Table 3 – Test parameters for Classes 1 and 2 . 23
Table 4 – Acceptance criteria for tests on materials . 26
Table 5 – Acceptance criteria for tests on garments . 26
Table A.1 – Repeatability and reproducibility values of test procedure . 28

– 4 – IEC 61482-1-2:2014 © IEC 2014

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LIVE WORKING – PROTECTIVE CLOTHING AGAINST
THE THERMAL HAZARDS OF AN ELECTRIC ARC –

Part 1-2: Test methods –
Method 2: Determination of arc protection class of material
and clothing by using a constrained and directed arc (box test)

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61482-1-2 has been prepared by IEC technical committee 78: Live
working.
This second edition cancels and replaces the first edition, published in 2007. This edition
constitutes a technical revision.
It includes the following significant technical changes with regard to the previous edition:
• new mean values of main control parameters arc energy and incident energy based on an
extended statistical database consisting of parameter values measured in four
laboratories;
• reduction of validity check ranges of main control parameters;

• determination of the incident energy by averaging the two sensor values of a test (instead
of considering each single sensor value);
• determination of the heat curves of transmitted incident energy and an amendment to the
heat flux acceptance criterion;
• information on precision (repeatability and reproducibility) of the test method;
• clarification of the scope;
• selection of the arc protection classes (test classes) by the amount of the arc energy and
incident energy instead of the short-circuit current;
• permitting electrode design without bores;
• recommendations of the heat resistance materials to be used for the box and for the test
plate;
• clarification of the conditions for cleaning and replacing the box;
• requirement for including in the test report the differences ∆E of the transmitted energy
i
values to the Stoll limit value at t and the information if the heat curves of transmitted
max
incident energy exceed the Stoll curve during the exposure time;
• preconditioning of the samples according to manufacturer’s instruction.
The text of this standard is based on the following documents:
FDIS Report on voting
78/1053/FDIS 78/1089/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this standard terms defined in Clause 3 appear in italics.
A list of all parts in the IEC 61482 series, published under the general title Live working –
Protective clothing against the thermal hazards of an electric arc, can be found on the IEC
website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 61482-1-2:2014 © IEC 2014

LIVE WORKING – PROTECTIVE CLOTHING AGAINST
THE THERMAL HAZARDS OF AN ELECTRIC ARC –

Part 1-2: Test methods –
Method 2: Determination of arc protection class of material
and clothing by using a constrained and directed arc (box test)

1 Scope
This part of IEC 61482 specifies procedures to test material and garments intended for use in
heat and flame-resistant clothing for workers if there is an electric arc hazard. A directed and
constrained electric arc in a test circuit is used to classify material and clothing in two defined
arc protection classes.
This International Standard is not dedicated toward measuring the arc rating values (ATPV ,
2 3
or EBT ). Procedures determining these arc rating values are prescribed in
ELIM
IEC 61482-1-1, using an open arc for testing.
Other effects than the thermal effects of an electric arc like noise, light emissions, pressure
rise, hot oil, electric shock, the consequences of physical and mental shock or toxic
influences are not covered by this standard.
Protective clothing for work intentionally using an electric arc, e.g. arc welding, plasma torch,
is not covered by this standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
ISO 9151:1995, Protective clothing against heat and flame – Determination of heat
transmission on exposure to flame
3 Terms, definitions and symbols
For the purposes of this document, the following terms, definitions and symbols apply.
3.1 Terms and definitions
3.1.1
arc current
I
arc
current actually flowing in the electric test circuit during arc duration (through the arc)
___________
ATPV = arc thermal performance value.
ELIM= incident energy limit
EBT= breakopen energy threshold

Note 1 to entry: Arc current is expressed in kA rms.
Note 2 to entry: The arc current flowing during arc duration fluctuates due to the non-linear arc impedance
stochastically varying with time.
3.1.2
arc duration
time duration of the arc
Note 1 to entry: Arc duration is expressed in ms.
3.1.3
arc energy
W
arc
electrical energy supplied to the arc and converted in the arc
Note 1 to entry: Arc energy is the sum of the instantaneous arc voltage values multiplied by the instantaneous arc
current values multiplied by the incremental time values during the arc duration.
Note 2 to entry: Arc energy is expressed in kJ or kW·s.
3.1.4
arc gap
distance between the arc electrodes
Note 1 to entry: Arc gap is expressed in mm.
3.1.5
arc protection class
category of arc thermal protection of material and protective clothing tested in the box test
(class 1 or class 2)
Note 1 to entry: The arc protection class is characterized by the test energy level of arc exposure (arc energy and
incident energy).
Note 2 to entry: Tested material and protective clothing show arc thermal protection at minimum up to the class
energy level. In general the actual exposure energy limit up to which the material and protective clothing provide
protection is higher.
3.1.6
arc thermal protection
degree of thermal protection offered against electric arc under specific arc testing conditions
Note 1 to entry: For materials, the arc thermal performance is obtained from the measurement of the transmitted
energy and by evaluation of other thermal parameters (burning time, hole formation, melting).
Note 2 to entry: For garments, the arc thermal performance is obtained by evaluation of thermal parameters
(burning time, hole formation, melting) and of the functioning of fasteners and accessories.
3.1.7
arc voltage
voltage across the arc
Note 1 to entry: Arc voltage is expressed in V.
3.1.8
burning time
after flame time
time for which a flaming of the test specimen is visible after the end of the electric arc
duration
Note 1 to entry: Burning time is expressed in s.

– 8 – IEC 61482-1-2:2014 © IEC 2014

3.1.9
calorimeter
assembly of a copper disc with attached thermocouple used for measuring the heat flux and
incident energy
3.1.10
charring
formation of carbonaceous residue as the result of pyrolysis or incomplete combustion
3.1.11
clothing
assembly of garments worn by workers
3.1.12
delta peak temperature
∆T
p
difference between the maximum temperature and the initial temperature of the sensor during
the test exposure time
Note 1 to entry: Delta peak temperature is expressed in °C.
Note 2 to entry: The symbol ∆T is used without index when testing with material; an additional index “0” is used
p
when testing without material for calibration (∆T ).
p0
3.1.13
direct exposure incident energy
E
i0
heat energy or incident energy emitted by the electric arc and received at a calorimeter
directly exposed to the arc without material influence
Note 1 to entry: Direct exposure incident energy is used for calibration.
2 2 2 4
Note 2 to entry: Direct exposure incident energy is expressed in kJ/m or kW·s/m (cal/cm ) .
3.1.14
dripping
material response evidenced by flowing of the fibre polymer
3.1.15
electric arc
self-maintained gas conduction for which most of the charge carriers are electrons supplied
by primary-electron emission
Note 1 to entry: During live working, the electric arc is generated by gas ionisation arising from an unintentional
electrical conducting connection or breakdown between live parts or a live part and the earth path of an electrical
installation or an electrical device. During testing, the electric arc is initiated by the blowing of a fuse wire.
[SOURCE: IEC 60050-121:1998, 121-13-12, modified – the Note 1 to entry has been added to
refer specifically to live working and arc testing.]
3.1.16
embrittlement
formation of a brittle residue as the result of pyrolysis or incomplete combustion
3.1.17
exposure time
total test time interval of observation and measurement
___________
4 2 2 2 2
Correlation: 1 cal/cm = 41,868 kJ/m ; 1 kJ/m = 0,023 885 cal/cm .

Note 1 to entry: Exposure time is expressed in s.
3.1.18
garment
single item of clothing which may consist of single or multiple layers
3.1.19
heat flux
thermal intensity of an electric arc indicated by the amount of energy transmitted per unit area
and time
Note 1 to entry: Heat flux is expressed in kW/m .
3.1.20
hole formation
existence of openings in the test specimen material with minimum 5 mm in any direction
3.1.21
ignition
initiation of flaming and combustion
3.1.22
incident energy
E
i
heat energy (total heat) received at a unit surface area as a result of an electric arc
Note 1 to entry: Incident energy is measured as a proportional peak temperature rise ∆T of a calorimeter sensor.
p
2 2 2
Note 2 to entry: Incident energy is expressed in kJ/m or kW·s/m (cal/cm ).
3.1.23
material
fabric or other substances of which the garment is made
Note 1 to entry: The material may consist of single or multiple layers.
3.1.24
material response
reaction of the material to an electric arc characterized by burning time (after flame), ignition,
hole formation, melting, dripping, charring, embrittlement, shrinkage and transmitted energy
3.1.25
melting
material response evidenced by softening and deformation
Note 1 to entry: Materials which melt are normally polymer(s).
3.1.26
prospective short-circuit current
predicted current flowing when the arc electrodes are connected by a conductor of negligible
impedance (short-circuit of supply)
Note 1 to entry: Prospective short-circuit current is expressed in kA rms.
Note 2 to entry: There is in general a difference between the actual arc current I and the test current I as
arc class
defined. The actual arc current flowing during the arc duration is smaller and fluctuates due to the non-linear arc
impedance stochastically varying with time. Reproducible test conditions may only be defined by means of the
prospective short-circuit current to be expected in case of impedance-less connected arc electrodes. This
prospective short-circuit current is, by the way, also a parameter which describes the practically interesting points
in the electrical systems or installations where arc exposure has to be considered.

– 10 – IEC 61482-1-2:2014 © IEC 2014

3.1.27
protective clothing
clothing which covers or replaces personal clothing, and which is designed to provide
protection against one or more hazards
[SOURCE: ISO 13688:2013, 3.5, modified – the definition has been modified to clarify it by
removing the unclear term “protector”]
3.1.28
sensor
assembly with a calorimeter and a non-conductive heat-resistant material in which the
calorimeter is mounted
3.1.29
shrinkage
material response evidenced by the reduction in specimen size
3.1.30
Stoll curve
an empirical predicted second-degree skin burn injury model defining a relationship between
the amount of thermal energy transferred to human tissue and the time of exposure
3.1.31
test current
I
class
prospective short-circuit current of the electric test circuit (predicted current)
Note 1 to entry: Test current is expressed in kA rms (symmetrical a.c. component).
3.1.32
test voltage
no-load a.c. voltage of the test circuit source at 50 Hz or 60 Hz
Note 1 to entry: Test voltage is expressed in V rms.
3.1.33
time to delta peak temperature
t
max
time from beginning of the initiation of the arc to the time the delta peak temperature is
reached
Note 1 to entry: Time to delta peak temperature is expressed in s.
3.1.34
transmitted energy
E
it
incident energy received at a calorimeter when testing material or clothing
Note 1 to entry: Transmitted energy is the fraction of the emitted incident energy which is transmitted through the
specimen.
2 2 2
Note 2 to entry: Transmitted energy is expressed in kJ/m or kW·s/m (cal/cm ).
3.1.35
X/R ratio
ratio of system inductive reactance to resistance
Note 1 to entry: The X/R ratio is proportional to the L/R ratio of time constant, and is, therefore, indicative of the
rate of decay of any d.c. offset. A large X/R ratio corresponds to a large time constant and a slow rate of decay.

3.2 Symbols and units used in this document
2 2 2
E incident energy kJ/m or kW·s/m (cal/cm )
i
2 2
1 cal/cm = 41,868 kJ/m ;
2 2
1 kJ/m = 0,023885 cal/cm
2 2 2
E direct exposure incident energy kJ/m or kW·s/m (cal/cm )
i0
2 2 2
E transmitted energy kJ/m or kW·s/m (cal/cm )
it
I arc current kA
arc
I test current (prospective short-circuit current) kA
class
t time to delta peak temperature s
max
T ambient temperature °C
a
T initial sensor temperature °C
W arc energy kJ, kW·s
arc
∆T delta peak temperature °C
p
delta peak temperature by calibration °C
∆T
p0
4 Principle of the test method
4.1 Material box test procedure
The box test method comprises two procedures: the material box test procedure and the
garment box test procedure.
The material box test procedure covered by this standard determines the behaviour of
materials when exposed to heat energy from electric arcs with specific characteristics.
With the material box test procedure the amount of heat energy transferred by the flat
material(s) is measured during and after exposure to a specified electric arc.
Material performance for this procedure is determined from the amount of heat transmitted
through the specimen(s) and other thermal parameters.
The heat flux of the exposure during the calibration shot and the heat flux transferred by the
test specimen(s) during a test shot are measured with copper calorimeters. The degree to
which the temperature of the calorimeters increases is a direct measure of the heat energy
received.
Heat transfer data is used to assess the occurrence of a second-degree burn using the Stoll
curve.
Material response shall be further described by recording the observed effects of the electric
arc exposure on the specimens.
4.2 Garment box test procedure
The garment box test procedure covered by this standard determines the behaviour of
garments when exposed to heat energy from electric arcs with specific characteristics.
Garment performance for this procedure is determined by evaluating the function of the
protective clothing after exposure to a specified electric arc, including all the garment
findings, sewing thread, fastenings and other accessories.
With the garment box test procedure, no heat flux will be measured.

– 12 – IEC 61482-1-2:2014 © IEC 2014

5 Significance and use of the test method
This test method is for testing material and garments of protective clothing used for
electrotechnical work if there is an electrical arc risk.
The test method permits to assess the arc thermal performance of materials (material box test
procedure) and garments (garment box test procedure) in terms of the energy level of the
selected protection class. The protection class energy level is represented by the level of the
arc energy and the corresponding level of the direct exposure incident energy according to
the test conditions.
NOTE 1 There are two protection classes: Class 1 represents a basic protection level, class 2 an increased
protection.
NOTE 2 In practice there can be situations with higher arc energy levels. Performing an electrical arc risk
assessment, the potential arc energy of an arc flash is determined for the specific equipment and network
conditions.
NOTE 3 This standard is for testing purposes. Guidance for the selection of the right protective clothing can be
found in IEC 61482-2 and in an ISSA Guideline [1] . Furthermore, there is a preliminary work of TC78 on a
technical report for correlating the results of arc test methods to electrotechnical applications in order to select the
proper electric arc protective equipment.
NOTE 4 Work continues to evaluate higher energy exposures.
With the box test set-up it is possible to evaluate materials and garments based on the use of
a directed and constrained electric arc under defined laboratory conditions. A practical
scenario concerning test set-up and test conditions, electrical and constructional parameters
is selected.
The heat energy transfer and impact of the test arc are due to radiation, convection by the hot
plasma and gas cloud, direct contact with the plasma cloud or parts of it, and hot molten
metal particles and splash.
The test box set-up is introduced to meet typical arc fault conditions and particularly to cover
actual arc exposure conditions in electrical equipment and switchgear, mainly in opened
compact equipment, e.g. service entrance boxes, cable distribution cabinets, distribution
substations or comparable installations where the electric arc is directed to the front of a
worker at the height of his breastbone.
NOTE 5 The test set-up configuration of this standard leads to high heat transmission. Other exposure conditions
such as vertical electrodes open-arc conditions are also covered by the test set-up.
The test set-ups maintain the specimen in a static vertical position and do not involve
movement except that resulting from the exposure.
The test method specifies a standard set of exposure conditions. Different exposure
conditions may produce more or less severe results. In addition to the standard set of
exposure conditions, other conditions representative of the expected hazard may be used.
6 Test apparatus
6.1 Test apparatus and test box
The test apparatus shall consist of the following elements:
– test box for both procedures;
___________
Numbers in square brackets refer to the Bibliography.

– two-sensor test plate for material box test procedure;
– mannequin for garment box test procedure;
– electric supply and electrode configuration;
– recorder;
– data acquisition system.
The test box arrangement (identical for both procedures) is shown in Figure 1.
The test box shall be of electrically and thermally non-conductive, heat resistant material.
If plaster is used, then plaster material which gives a smooth and solid surface shall be used.
TM
NOTE Besides others, the use of Keraquick moulding compound, a ceramic powder for relief casting, has
shown suitable results.
___________
TM
Keraquick is the trade name of a product supplied by KnorrPrandell GmbH, 96215 Lichtenfels, Germany. This
information is given for the convenience of users of this standard and does not constitute an endorsement by
IEC of the product named. Equivalent products may be used if they can be shown to lead to the same results.

– 14 – IEC 61482-1-2:2014 © IEC 2014

Dimensions in millimetres
Front view
IEC
Cut A profile
Key
1 box, non-conductive heat resistant material (e.g. plaster)
insulating plate, thickness > 15
electrode ∅ 25 ± 0,1 (aluminum)
4 electrode ∅ 25 ± 0,1 (copper)
Figure 1 – Test box
6.2 Material box test procedure
6.2.1 Arrangement of the material box test procedure
The material box test procedure is used to measure and find material response to an arc
exposure when tested in a flat configuration. A quantitative measurement of the arc thermal
performance by means of the heat flux or energy transmitted through the material is made.
The arrangement is shown in Figure 2.
The distance from electrode (centre line) to test plate (surface) shall be 300 mm ± 5 mm.
The gap between electrodes shall be 30 mm ± 1 mm (arc gap).
Dimensions in millimetres
R
IEC
Key
test plate with specimen (400 × 400, thickness >10 ) or test mannequin (torso)
2 cable connector
3 test box
connecting cable (R > 1 000)
5 horizontal centre line
Figure 2 – Test set-up
– 16 – IEC 61482-1-2:2014 © IEC 2014

6.2.2 Test plate (panel) construction
The test plate construction is shown in Figure 3.
The test plate shall be of non-conductive heat resistant material (e.g. Marinite A, Monolux
TM
500, asbestosfree transite board, oven insulation, phenolic resin PF CP 201 ).
Size: (400 ± 10) mm × (400 ± 10) mm
Thickness: minimum 10 mm
Sensors: sensor with calorimeters according to 5.2 of ISO 9151:1995 with
thermocouples type T
number: 2
configuration: in the test plate, see Figure 3.
Dimensions in millimetres
IEC
Key
1 test plate (see also Figure 2)
2 horizontal centre line
3 centre line parallel to the arc axis
4 sensor (calorimeter in mounting board)
Figure 3 – Test plate with sensors
(calorimeters in mounting boards)
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TM
7 Marinite A, Monolux 500 and phenolic resin PF CP 201 are examples of suitable products available
commercially. This information is given for the convenience of users of this standard and does not constitute an
endorsement by IEC of the product named. Equivalent products may be used if they can be shown to lead to
the same results.
6.2.3 Sensor construction
The sensor consists of a calorimeter embedded in an insulating board. The sensor diameter is
90 mm ± 5 mm (see Figure 3). The calorimeter consists of a 18 g ± 1 g copper disc of
40 mm ± 0,1 mm in diameter, thickness of 1,6 mm ± 0,1 mm, a purity of at least 99 % and of a
copper-constantan thermocouple T type. The disc shall be accurately weighted before
assembly. The calorimeter shall be constructed from grade copper.
The copper-constantan wire thermocouple (type T) shall be mounted with the constantan wire
in the copper disc centre and the copper wire at any distance outside the disc centre. The
disc of the calorimeter shall be embedded in an insulating board. It shall be mounted flush
with the surface of this mounting board. The surface area of the copper disc intended for heat
receiving shall be covered by a thin layer of optical-black high temperature paint with an
emissivity > 0,9.
6.2.4 Sensor response
The conversion of the sensor response in the form of the temperature rise in °C to heat
energy (incident energy) in units of kJ/m is to be done by multiplying the delta temperature
values by the constant factor 5,52 kJ/m °C.
NOTE 1 The constant factor (sensor constant) is based on an average value for the copper thermal capacity C
p
equal to 0,385 J/g°C (80°C) in the tested temperature range, multiplied by the calorimeter copper plate mass of
18 g (resulting from a diameter of 40 mm and a thickness of 1,6 mm) and divided by the plate cross sectional area
of 12,56 cm .
NOTE 2 Another way to consider the temperature dependency of copper thermal capacity C is to use the
p
correction described in IEC 61482-1-1.
6.3 Garment box test procedure
6.3.1 Arrangement of the garment box test procedure
Instead of flat panels, a mannequin shall be employed for the garment box test procedure.
The procedure is used to test the function of the protective clothing after an arc exposure
including all the garment finding
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