IEC 61482-1-2:2014

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)

IEC 61482-1-2:2014 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, ELIM, or EBT). Procedures determining these arc rating values are prescribed in 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. This second edition cancels and replaces the first edition, published in 2007. This edition constitutes a technical revision which 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;
- clarification of the scope;
- and selection of the arc protection classes (test classes) by the amount of the arc energy and incident energy instead of the short-circuit current.

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)

L'IEC 61482-1-2:2014 spécifie des procédures d'essai des matériaux et des articles d'habillement destinés à être utilisés dans les vêtements résistant à la chaleur et à la flamme pour les travailleurs, en cas de danger d'arc (de défaut) électrique. Dans un circuit d'essai, un arc électrique dirigé et contraint permet de classer les matériaux et les vêtements dans deux classes de protection contre les arcs définies. Cette Norme Internationale n'est pas destinée à mesurer les valeurs de performance de l'arc (ATPV, ELIM, ou EBT). Les procédures déterminant les valeurs de performance thermique de l'arc sont présentées dans l'IEC 61482-1-1. Elles utilisent un arc à l'air libre pour les essais. D'autres effets que les effets thermiques d'un arc électrique tel que le bruit, les émissions de lumière, la montée de pression, l'huile chaude, les chocs électriques, les conséquences des chocs physiques et mentaux ou les influences toxiques ne sont pas couvert par cette norme. Les vêtements de protection destinés au travail intentionnel avec un arc électrique, par exemple soudure l'arc, torche au plasma, ne sont pas couvert par cette norme. Cette deuxième édition annule et remplace la première édition parue en 2007. Cette édition constitue une révision technique qui inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- nouvelles valeurs moyennes des paramètres de commande énergie d'arc et énergie incidente selon une base de données statistique étendue des valeurs de paramètre mesurées dans quatre laboratoires;
- réduction des plages de contrôle de validité des principaux paramètres de commande;
- détermination de l'énergie incidente par calcul de la moyenne de deux valeurs de capteur d'un essai (au lieu de considérer chaque valeur unique de capteur);
- détermination des courbes thermiques de l'énergie incidente émise et un amendement au critère d'acceptation de flux thermique;
- clarification du domaine d'application;
- et sélection des classes de protection contre l'arc (classes d'essai) par la quantité d'énergie d'arc et d'énergie incidente à la place du courant de court-circuit.

General Information

• Status: Published
• Publication Date: 08-Oct-2014
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 13.220.40 - Ignitability and burning behaviour of materials and products
• ICS: 29.260.99 - Other electrical equipment for working in special conditions
• Technical Committee: TC 78 - Live working
• Current Stage: PPUB - Publication issued
• Start Date: 09-Oct-2014
• Completion Date: 09-Oct-2014

Standards Content (sample)

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)
IEC 61482-1-2:2014-10(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
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

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 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

---------------------- Page: 4 ----------------------
IEC 61482-1-2:2014 © IEC 2014 – 3 –

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

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

---------------------- Page: 5 ----------------------
– 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

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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;
---------------------- Page: 6 ----------------------
IEC 61482-1-2:2014 © IEC 2014 – 5 –

• 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

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.
---------------------- Page: 7 ----------------------
– 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
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
---------------------- Page: 8 ----------------------
IEC 61482-1-2:2014 © IEC 2014 – 7 –
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
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.
---------------------- Page: 9 ----------------------
– 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

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

when testing without material for calibration (∆T ).
3.1.13
direct exposure incident energy

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 .
---------------------- Page: 10 ----------------------
IEC 61482-1-2:2014 © IEC 2014 – 9 –
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 dire

...