Safeguards againts accidentally caused candle flame ignition for audio/video, communication and information technology equipment

IEC/TS 62441:2011 Introduces safeguards to reduce the likelihood of room flash-over as a result of accidental ignition of exterior housings of audio/video and information communication technology products likely to be used in the home, caused by a candle flame. This second edition of IEC 62441 cancels and replaces the first edition published in 2006 and constitutes a technical revision. This edition includes the following technical changes with respect to the previous edition:
- acceptance of wood with a minimum thickness as equivalent to V-1;
- interpretation information regarding vertical surfaces.

Mesures de protection contre l'embrasement accidentel dû à une flamme de bougie dans les équipements audio/vidéo, des technologies de la communication et de l'information

La CEI/TS 62441:2011 introduit des mesures de protection destinées à réduire les risques d'embrasement éclair d'une pièce dû à une flamme de bougie, résultant de l'embrasement accidentel de l'habillage extérieur des appareils audio/vidéo, des appareils de technologies de l'information et de la communication, utilisés généralement en milieu résidentiel. Cette deuxième édition de la CEI 62441 annule et remplace la première édition parue en 2006 et constitue une révision technique. Cette édition comprend les changements suivants par rapport à l'édition précédente:
- acceptation du bois avec une épaisseur minimum équivalente à V-1;
- information sur l'interprétation concernant les surfaces verticales.

General Information

Status
Published
Publication Date
09-Feb-2011
Current Stage
PPUB - Publication issued
Start Date
10-Feb-2011
Completion Date
10-Feb-2011
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IEC/TS 62441
Edition 2.0 2011-02
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
colour
inside
Safeguards against accidentally caused candle flame ignition
for audio/video, communication and information technology equipment
Mesures de protection contre l’embrasement accidentel dû à une flamme de
bougie dans les équipements audio/video, des technologies de la
communication et de l'information
IEC/TS 62441:2011
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC/TS 62441
Edition 2.0 2011-02
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
colour
inside
Safeguards against accidentally caused candle flame ignition
for audio/video, communication and information technology equipment
Mesures de protection contre l’embrasement accidentel dû à une flamme de
bougie dans les équipements audio/video, des technologies de la
communication et de l'information
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX L
ICS 35.260; 97.020 ISBN 978-2-88912-364-3
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – TS 62441  IEC:2011
CONTENTS

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

1 Scope ............................................................................................................................... 6

2 Normative references ....................................................................................................... 6

3 Terms and definitions ....................................................................................................... 6

4 Warning for users ............................................................................................................. 7

5 Control of fire growth ........................................................................................................ 8

5.1 General ................................................................................................................... 8

5.2 Determination of candle flame accessible areas ...................................................... 8

5.3 Test methodology .................................................................................................... 9

5.3.1 Conditioning ................................................................................................ 9

5.3.2 Positioning the individual item ..................................................................... 9

5.3.3 Ignition source ........................................................................................... 10

5.4 Test for sustained flaming ..................................................................................... 10

Bibliography .......................................................................................................................... 11

Figure 1 – Examples of candle flame accessible areas ........................................................... 9

Figure 2 – Positioning of the needle flame burner ................................................................. 10

---------------------- Page: 4 ----------------------
TS 62441  IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFEGUARDS AGAINST ACCIDENTALLY
CAUSED CANDLE FLAME IGNITION
FOR AUDIO/VIDEO, COMMUNICATION
AND INFORMATION TECHNOLOGY EQUIPMENT
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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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.

The main task of IEC technical committees is to prepare International Standards. In

exceptional circumstances, a technical committee may propose the publication of a technical

specification when

• the required support cannot be obtained for the publication of an International Standard,

despite repeated efforts, or

• The subject is still under technical development or where, for any other reason, there is

the future but no immediate possibility of an agreement on an International Standard.

Technical specifications are subject to review within three years of publication to decide

whether they can be transformed into International Standards.

IEC 62441, which is a technical specification, has been prepared by IEC technical committee

108: Safety of electronic equipment within the field of audio/video, information technology and

communication technology.
---------------------- Page: 5 ----------------------
– 4 – TS 62441  IEC:2011

This second edition of IEC 62441 cancels and replaces the first edition published in 2006 and

constitutes a technical revision. This edition includes the following technical changes with

respect to the previous edition:
– acceptance of wood with a minimum thickness as equivalent to V-1;
– interpretation information regarding vertical surfaces.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
108/391/DTS 108/412/RVC

Full information on the voting for the approval of this technical specification 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.

The following print types are used:
– requirements proper and normative annexes: in roman type;
– compliance statements and test specifications: in italic type;
– notes/explanatory matter: in small roman type;
– terms that are defined in Clause 3: bold.

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
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates

that it contains colours which are considered to be useful for the correct

understanding of its contents. Users should therefore print this document using a

colour printer.
---------------------- Page: 6 ----------------------
TS 62441  IEC:2011 – 5 –
INTRODUCTION

The first version of this technical specification was discussed at the TC108 plenary meeting in

Matsue, Japan in October 2008. It was decided to extend the TS for another three year period

and to implement some changes as previously agreed in several TC108 meetings. The text of

this technical specification is based on the outcome of these discussions.

In line with SMB decision 135/20 and document AC/22/2009, it is anticipated that the next

step for this document would be a proposal for publication as an International Standard,

taking into account any further developments regarding the improvement of these
requirements.

It should be noted that the Fire Team of the HBSDT (Hazard based standard development

team) developed requirements on a Heat Release Rate Performance Test and recommended

a peak Heat Release Rate (pHRR) value of 50 KW for equipment covered by the standard. It

also generated test data for the specific pre-selection criteria for equipment, such as

keyboards, that have fuels that are predominantly horizontal in their construction.

Development testing that had been conducted included assessment of products that were

difficult to ignite with a candle and that passed preliminary pHRR testing with significant

margin. However, these products commonly use fuels that may not pass
1) the flammability rating,
2) the material weight exemption, or
3) the sustained ignition testing.

These additional requirements and test methods did not give the same level of reproducibility

that would be desired for inclusion as normative requirements in a standard, and are therefore

not currently included in this technical specification. It should be noted that additional work is

being undertaken to improve on the pHRR test procedure so that better reproducibility can be

attained.
---------------------- Page: 7 ----------------------
– 6 – TS 62441  IEC:2011
SAFEGUARDS AGAINST ACCIDENTALLY
CAUSED CANDLE FLAME IGNITION
FOR AUDIO/VIDEO, COMMUNICATION
AND INFORMATION TECHNOLOGY EQUIPMENT
1 Scope

This technical specification introduces safeguards to reduce the likelihood of room flash-over

as a result of accidental ignition of exterior housings of audio/video and information

communication technology products likely to be used in the home, caused by a candle flame.

NOTE According to AC/22/2009 and SMB decision 135/20, this technical specification should currently only be

used for television sets. It can be used for other products only if a risk assessment indicates problems with these

products.
2 Normative references

The following referenced documents are indispensable for the application 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.

IEC 60695-11-5, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method –

Apparatus, confirmatory test arrangement and guidance

IEC 60695-11-10, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical

flame test methods

IEC 60695-11-20, Fire hazard testing – Part 11-20: Test flames – 500 W flame test methods

3 Terms and definitions
3.1
combustible material
organic material, capable of combustion by a candle flame

NOTE 1 Metal or ceramic are examples of materials that are not combustible by a candle flame.

NOTE 2 All plastic materials are considered combustible by a candle flame, regardless of flammability

classification.
3.2
flammability classification of materials
classification of the burning and extinguishing behaviour of a material

NOTE 1 Material classes are defined in 3.2.1 to 3.2.4. Where a certain class of material is required, a material

with a better classification is always acceptable.

NOTE 2 When applying the requirements in this technical specification, a material of 5VA class material is

regarded as better than 5VB class material, 5VB class material better than V-0 class material and V-0 class

material better than V-1 class material (see 5.1).

NOTE 3 When applying the requirements in this technical specification, V-2 class material or HB class material is

considered less than V-1 class material (see 5.1). For further details regarding these flame classifications, see

IEC 60695-11-10.
---------------------- Page: 8 ----------------------
TS 62441  IEC:2011 – 7 –
3.2.1
V-0 class material

material tested in the thinnest significant thickness used and classified V-0 according to

IEC 60695-11-10
3.2.2
V-1 class material

material tested in the thinnest significant thickness used and classified V-1 according to

IEC 60695-11-10
3.2.3
5VA class material

material tested in the thinnest significant thickness used and classified 5VA according to

IEC 60695-11-20
3.2.4
5VB class material

material tested in the thinnest significant thickness used and classified 5VB according to

IEC 60695-11-20
3.3
individual item

equipment or a part of the equipment, with its own exterior housing, that is not required to be

in physical contact with another equipment or part of the other equipment for its normal

operation

NOTE An individual item may be electrically connected to other equipment and may or may not contain its own

power source. Examples include keyboards, display units, speakers, etc.
3.4
candle flame accessible area

an area of combustible material on the exterior surface of an individual item to which the

simulated candle flame is applied
NOTE See 5.2 for the criteria.
4 Warning for users
If the individual item has an outer housing having a mass of more than 300 g of

combustible material, of which at least part is within a candle flame accessible area, users

shall be informed about the risks associated with the burning of candles in the user

instructions, available with the equipment, or on a warning label on the equipment.

If a symbol is used, it shall be in accordance with the example shown below (currently

IEC 60417-Pr10-040) and it shall have a minimum height of 10 mm.
NOTE The colours of ISO 3864 do not apply to the symbol.

If text is used, it shall have the following or similar wording, with a minimum letter height of

3 mm:
---------------------- Page: 9 ----------------------
– 8 – TS 62441  IEC:2011
WARNING
To prevent the spread of fire, keep candles or other open flames
away from this product at all times.
Compliance is checked by inspection.
5 Control of fire growth
5.1 General

An individual item, if accidentally subjected to a candle flame, shall reduce the likelihood of

spread of fire to adjacent items by limiting the fire growth.

An individual item having a candle flame accessible area is considered to comply if it

meets the requirements of either a), b), or c) below:

a) the total mass of the combustible materials located at the outer surface does not exceed

300 g; or

b) the combustible material used in candle flame accessible areas is made of V-1 class

material; or

NOTE 1 Application of the test flame in a horizontal position (see Figure 2) results in a portion of the flame

extending above the centre-line application point, which makes it necessary to consider the areas immediately

above the centre-line with respect to their flame class properties or their combustibility [see also 5.1c) below].

c) the combustible materials used in candle flame accessible areas do not exhibit flaming

for more than 3 min as determined by the test of 5.4.
Individual parts
– located in a candle flame accessible area, and
– made of combustible material rated less than V-1 class material
are exempt from b) and c) above provided that

– the mass of combustible material rated less than V-1 class material of each individual

part does not exceed 25 g, and

– the total mass for all such individual parts does not exceed 10 % of the total mass of the

combustible material, with a limit of 300 g, located at the exterior surface of the

individual item.

NOTE 2 Examples of such individual parts are knobs, switches, covers, and dial faces.

When determining the 300 g mass of the exterior enclosure or the mass of the individual part,

only the mass between the outermost surface and a plane that is in line with the inner surface

of the exterior enclosure needs to be taken into account.

Wood and wood-based material with a thickness of at least 6 mm is considered to fulfill the

V-1 class material requirement.

NOTE 3 It is recommended that the quantity of environmentally unfriendly flame retardant materials should be

kept as low as possible.

Compliance is checked by inspection, measurement and, if necessary, by the test of 5.4.

5.2 Determination of candle flame accessible areas

Candle flame accessible areas are considered to be the following exterior surfaces of an

individual item:
---------------------- Page: 10 ----------------------
TS 62441  IEC:2011 – 9 –

– surfaces that are vertical to or overhanging the supporting surface and are located

between 10 mm and 150 mm directly above the supporting surface (see Figures 1a and

1b ); and

– the bottom of the individual item, unless it rests directly on the supporting surface or is

within 10 mm of the supporting surface in its normal position of use.

NOTE 1 The term vertical does not mean a perfectly vertical position. It should be interpreted as any surface that

can be touched by the flame of a candle of 150 mm height and 20 mm diameter while the candle is still touching

the supporting surface. A typical candle used in the home is assumed to be 20 mm diameter.

When determining the candle flame accessible areas, doors, drawers and user removable

parts are closed or placed in the intended positions.
150 mm
10 mm
IEC 2243/06
IEC 2244/06
Figure 1a – Equipment illustrating Figure 1b – Equipment illustrating
straight vertical sides a raised or stepped portion
Figure 1 – Examples of candle flame accessible areas

NOTE 2 The identified cross-hatched areas give the general principle for the application areas of the test flame. A

practical approach should be used to determine the candle flame accessible areas. In general, top surfaces of

equipment are not considered, however, vertical surfaces having a height of greater than 10 mm that are adjacent to

large horizontal surfaces of the individual item itself, such as a raised or stepped portion of an external enclosure,

may also need to be considered.
5.3 Test methodology
5.3.1 Conditioning

The individual item is conditioned for a minimum of 24 h at 23 °C ± 2 °C and 50 % ± 5 %

relative humidity. Once removed from the conditioning chamber, the individual item is tested

within 1 h. The individual item shall be tested in a laboratory atmosphere of 15 °C to 35 °C

and 45 % to 75 % relative humidity.
5.3.2 Positioning the individual item
Individual items are tested separately.
The individual item is not energized during the test.
The individual item is tested without consumable materials and media.

The individual item is placed on a smooth, flat non-combustible supporting surface. The

supporting surface shall be of sufficient size to accept the placement of the individual item

within the boundaries of the surface and to accept any potential collapse of the individual

item during the test. The supporting surface shall be a single piece of material without any

joints.
---------------------- Page: 11 ----------------------
– 10 – TS 62441  IEC:2011
The supporting surface shall be cleaned of any residue before each test.
5.3.3 Ignition source

The needle burner and the 12 mm test flame as specified in IEC 60695-11-5 are used.

5.4 Test for sustained flaming

Following the conditioning and applying the methodology of 5.3, the tip of the burner tube

shall be positioned at a distance of 5 mm ± 0,5 mm from the candle flame accessible area

(see Figure 2), with the burner tube in a horizontal position (± 5º). The centre-line of the

burner shall be positioned within the candle flame accessible area. The test flame shall

remain stationary for 3 min even if the surface melts or shrinks away from the flame. If any

flaming does not exceed 3 min after the removal of test flame, including flaming of materials

that may have dripped from the individual item, the test flame shall be moved to another

candle flame accessible area and the procedure repeated until each relevant surface within

the candle flame accessible area has been tested.

NOTE Relevant surfaces are considered to be those with different characteristics, such as shape, thickness or

openings.

If the flaming time of each test does not exceed 3 min, the individual item is considered to

comply with 5.1.

During the test, the individual item is placed in any position that can be expected during

normal use.
Test specimen
5 mm ± 0,5 mm
10 mm to 150 mm
Supporting surface
IEC 2245/06
Figure 2 – Positioning of the needle flame burner
---------------------- Page: 12 ----------------------
TS 62441  IEC:2011 – 11 –
Bibliography
IEC 60417, Graphical symbols for use on equipment
ISO 3864 (all parts), Graphical symbols – Safety colours and safety signs
___________
---------------------- Page: 13 ----------------------
– 12 – TS 62441  CEI:2011
SOMMAIRE

AVANT-PROPOS .................................................................................................................. 13

INTRODUCTION ................................................................................................................... 15

1 Domaine d’application .................................................................................................... 16

2 Références normatives ................................................................................................... 16

3 Termes et définitions ...................................................................................................... 16

4 Avertissement à destination des utilisateurs ................................................................... 17

5 Contrôle de la progression du feu ................................................................................... 18

5.1 Généralités ............................................................................................................ 18

5.2 Détermination des zones accessibles aux flammes de bougie ............................... 19

5.3 Méthodologie d’essai ............................................................................................. 20

5.3.1 Conditionnement ....................................................................................... 20

5.3.2 Positionnement de l’élément individuel ...................................................... 20

5.3.3 Source d’allumage ..................................................................................... 20

5.4 Essai avec des flammes soutenues ....................................................................... 20

Bibliographie ......................................................................................................................... 22

Figure 1 – Exemples de zones accessibles aux flammes de bougie ...................................... 19

Figure 2 – Positionnement du brûleur aiguille........................................................................ 21

---------------------- Page: 14 ----------------------
TS 62441  CEI:2011 – 13 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
MESURES DE PROTECTION CONTRE L’EMBRASEMENT
ACCIDENTEL DÛ À UNE FLAMME DE BOUGIE
DANS LES ÉQUIPEMENTS AUDIO/VIDEO,
DES TECHNOLOGIES DE LA COMMUNICATION
ET DE L'INFORMATION
AVANT-PROPOS

1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisa

...

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