IEC 60335-2-96:2024

IEC 60335-2-96 ®
Edition 3.0 2024-10
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances – Safety –
Part 2-96: Particular requirements for flexible sheet heating elements for room
heating
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IEC 60335-2-96 ®
Edition 3.0 2024-10
COMMENTED VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances – Safety –
Part 2-96: Particular requirements for flexible sheet heating elements for room
heating
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 97.100.10, 13.120 ISBN 978-2-8322-0050-6
– 2 – IEC 60335-2-96:2024 CMV © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 General requirement . 10
5 General conditions for the tests . 10
6 Classification . 11
7 Marking and instructions . 11
8 Protection against access to live parts . 16
9 Starting of motor-operated appliances . 17
10 Power input and current . 17
11 Heating . 17
12 Void Charging of metal-ion batteries . 21
13 Leakage current and electric strength at operating temperature . 21
14 Transient overvoltages . 22
15 Moisture resistance . 22
16 Leakage current and electric strength . 22
17 Overload protection of transformers and associated circuits . 23
18 Endurance . 23
19 Abnormal operation . 26
20 Stability and mechanical hazards . 26
21 Mechanical strength . 26
22 Construction . 28
23 Internal wiring . 30
24 Components . 30
25 Supply connection and external flexible cords . 30
26 Terminals for external conductors . 31
27 Provision for earthing . 31
28 Screws and connections . 31
29 Clearances, creepage distances and solid insulation . 31
30 Resistance to heat and fire . 32
31 Resistance to rusting . 32
32 Radiation, toxicity and similar hazards . 32
Annexes . 46
Annex AA (informative) Summary of installation instructions . 47
Bibliography . 50
List of comments . 51
Figure 101 – Arrangement for testing heating units in timber ceilings . 33
Figure 102 – Arrangement for testing modular heating units . 34
Figure 103 – Arrangement for testing heating units in timber floors . 35

Figure 104 – Arrangement for testing heating units above timber floors . 36
Figure 105 – Arrangement for testing heating units below concrete . 37
Figure 107 – Arrangement for testing heating units in timber floors and ceilings in
combination . 39
Figure 108 – Arrangement for testing heating units in timber walls . 40
Figure 109 – Arrangement for testing heating units in both sides of timber wall
applications . 41
Figure 110 – Arrangement for testing heating units intended to be installed in a wall of
concrete or similar materials . 42
Figure 111 – Arrangement for testing heating units against wall of concrete or similar
materials . 43
Figure 112 – Jig for locating the contact needle . 44
Figure 113 – Arrangement for measuring capacitive currents . 45
Table 101 – Temperature rise limits for surfaces . 21
Table AA.1 – Summary of installation instructions . 48

– 4 – IEC 60335-2-96:2024 CMV © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-96: Particular requirements for flexible
sheet heating elements for room heating

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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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shall not be held responsible for identifying any or all such patent rights.
This commented version (CMV) of the official standard IEC 60335-2-96:2024 edition 3.0
allows the user to identify the changes made to the previous IEC 60335-2-96:20019
edition 2.0. Furthermore, comments from IEC TC 61 experts are provided to explain the
reasons of the most relevant changes, or to clarify any part of the content.
A vertical bar appears in the margin wherever a change has been made. Additions are in
green text, deletions are in strikethrough red text. Experts' comments are identified by a
blue-background number. Mouse over a number to display a pop-up note with the
comment.
This publication contains the CMV and the official standard. The full list of comments is
available at the end of the CMV.

IEC 60335-2-96 has been prepared by IEC technical committee 61: Safety of household and
similar electrical appliances. It is an International Standard.
This third edition cancels and replaces the second edition published in 2019. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) alignment with IEC 60335-1:2020;
b) conversion of some notes to normative text (Clause 1, 5.2, 7.12.101);
c) correction to reinstate the touch current limit in 22.105.
The text of this International Standard is based on the following documents:
Draft Report on voting
61/7279/FDIS 61/7304/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts of the IEC 60335 series, under the general title: Household and similar
electrical appliances – Safety, can be found on the IEC website.
This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and its
amendments unless that edition precludes it; in that case, the latest edition that does not
preclude it is used. It was established on the basis of the sixth edition (2020) of that standard.
NOTE 1 When "Part 1" is mentioned in this standard, it refers to IEC 60335-1.
This part 2 supplements or modifies the corresponding clauses in IEC 60335-1, so as to convert
that publication into the IEC standard: Particular requirements for flexible sheet heating
elements for room heating.
When a particular subclause of Part 1 is not mentioned in this part 2, that subclause applies as
far as is reasonable. When this standard states "addition", "modification" or "replacement", the
relevant text in Part 1 is to be adapted accordingly.
NOTE 2 The following numbering system is used:
– subclauses, tables and figures that are numbered starting from 101 are additional to those in Part 1;
– unless notes are in a new subclause or involve notes in Part 1, they are numbered starting from 101, including
those in a replaced clause or subclause;
– additional annexes are lettered AA, BB, etc.
NOTE 3 The following print types are used:
– requirements: in roman type;
– test specifications: in italic type;
– notes: in small roman type.
– 6 – IEC 60335-2-96:2024 CMV © IEC 2024
Words in bold in the text are defined in Clause 3. When a definition concerns an adjective, the adjective and the
associated noun are also in bold.
The following additional differences exist in the countries indicated below.
– 1: Flexible sheet heating elements that are cut on site are not allowed (France).
– 7.12.1 c): The instructions in timber floors shall state that the heating unit is to be covered
with additional insulation, be supplied through an isolating transformer, or be class II
(Sweden).
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations can need a transitional period following publication of a new, amended or revised IEC publication in
which to make products in accordance with the new requirements and to equip themselves for conducting new or
revised tests.
It is the recommendation of the committee that the content of this publication be adopted for implementation nationally
not earlier than 12 months or later than 36 months from the date of publication.

IMPORTANT – The "colour inside" logo on the cover page of this document 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.

INTRODUCTION
It has been assumed in the drafting of this International Standard that the execution of its
provisions is entrusted to appropriately qualified and experienced persons.
Guidance documents concerning the application of the safety requirements for appliances can
be accessed via TC 61 supporting documents on the IEC website
https://www.iec.ch/tc61/supportingdocuments
This information is given for the convenience of users of this International Standard and does
not constitute a replacement for the normative text in this standard.
This standard recognizes the internationally accepted level of protection against hazards such
as electrical, mechanical, thermal, fire and radiation of appliances when operated as in normal
use taking into account the manufacturer's instructions. It also covers abnormal situations that
can be expected in practice and takes into account the way in which electromagnetic
phenomena can affect the safe operation of appliances.
This standard takes into account the requirements of IEC 60364 as far as possible so that there
is compatibility with the wiring rules when the appliance is connected to the supply mains.
However, national wiring rules may can differ.
If an appliance within the scope of this standard also incorporates functions that are covered
by another part 2 of IEC 60335, the relevant part 2 is applied to each function separately, as
far as is reasonable. If applicable, the influence of one function on the other is taken into
account.
When a part 2 standard does not include additional requirements to cover hazards dealt with in
Part 1, Part 1 applies.
NOTE 1 This means that the technical committees responsible for the part 2 standards have determined that it is
not necessary to specify particular requirements for the appliance in question over and above the general
requirements.
This standard is a product family standard dealing with the safety of appliances and takes
precedence over horizontal and generic standards covering the same subject.
NOTE 2 Horizontal and generic standards Horizontal publications, basic safety publications and group safety
publications covering a hazard are not applicable since they have been taken into consideration when developing
the general and particular requirements for the IEC 60335 series of standards. For example, in the case of
temperature requirements for surfaces on many appliances, generic standards, such as ISO 13732-1 for hot surfaces,
are not applicable in addition to Part 1 or part 2 standards. 1
An appliance that complies with the text of this standard will not necessarily be considered to
comply with the safety principles of the standard if, when examined and tested, it is found to
have other features which impair the level of safety covered by these requirements.
An appliance employing materials or having forms of construction differing from those detailed
in the requirements of this standard may be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, may be considered to comply with the
standard.
NOTE 3 Standards dealing with non-safety aspects of household appliances are:
– IEC standards published by TC 59 concerning methods of measuring performance;
– CISPR 11, CISPR 14-1 and relevant IEC 61000-3 series standards concerning electromagnetic emissions;
– CISPR 14-2 concerning electromagnetic immunity;
– IEC standards published by TC 111 concerning environmental matters. 2

– 8 – IEC 60335-2-96:2024 CMV © IEC 2024
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-96: Particular requirements for flexible
sheet heating elements for room heating

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with the safety of flexible sheet heating elements intended to
be incorporated into floors and walls below 1,2 m and above 2,3 m and in ceilings, their rated
voltage being not more than 250 V for single-phase installations and 480 V for other
installations including direct current (DC) supplied appliances. 3
Flexible sheet heating elements are converted into heating units that are incorporated in the
building in accordance with the instructions after which the required level of protection against
hazards is achieved.
NOTE 101 Attention is drawn to the fact that
– in many countries, different wiring rules apply;
– for heating units intended to be used in vehicles or on-board ships or aircraft, additional
requirements can be necessary;
– in many countries, additional requirements are specified by the national authorities for fire
protection, the national authorities for building regulations, the national health authorities,
the national authorities responsible for the protection of labour and similar authorities.
NOTE 102 This standard does not apply to
– heating units intended exclusively for industrial purposes;
– heating units intended to be used in locations where special conditions prevail, such as
the presence of a corrosive or explosive atmosphere (dust, vapour or gas);
– blankets, pads, clothing and similar flexible heating appliances (IEC 60335-2-17);
– foot warmers and heating mats (IEC 60335-2-81);
– heated carpets and for heating units for room heating installed under removable floor
coverings (IEC 60335-2-106);
– flexible sheet heating elements incorporated in other appliances.
2 Normative references
This clause of Part 1 is applicable except as follows.
Addition:
IEC 60364-7-701:2006, Low-voltage electrical installations – Part 7-701: Requirements for
special installations or locations – Locations containing a bath or shower
IEC 60884-1:20022022, Plugs and socket-outlets for household and similar purposes – Part 1:
General requirements
IEC 60884-1:2002/AMD1:2006
IEC 60884-1:2002/AMD2:2013
ISO 3864-1, Graphical symbols – Safety colours and safety signs – Part 1: Design principles
for safety signs and safety markings
3 Terms and definitions
This clause of Part 1 is applicable except as follows.
3.1 Definitions relating to physical characteristics
Replacement:
3.1.9 Modification: 4
normal operation
Replace the first paragraph with the following:
operation of the heating unit after incorporation into the building in accordance with the
instructions.
Flexible sheet heating elements, the current of which can vary depending on the length of the
flexible sheet heating elements and those that can supply other flexible sheet heating
elements are loaded so that the current marked on the flexible sheet heating elements flows
through the heating unit.
Heating units for storage heating applications are charged for 75 % of the rated charging
period.
3.1.101
rated charging period
longest uninterrupted charging period assigned to the heating unit by the manufacturer
3.2 Definitions relating to means of connection
3.2.1 Replacement:
supply leads
set of wires intended for connecting the appliance to fixed wiring
3.5 Definitions relating to types of appliances
3.5.4 Addition:
Note 101 to entry: Heating units are considered to be fixed appliances.
3.5.101
flexible sheet heating element
heating element consisting of sheets of electrical insulation laminated with electrical resistance
material, or a base material on which electrically insulated heating wires are fixed
Note 1 to entry: This definition does not preclude other methods of combining the insulation and resistance
materials.
___________
There exists a consolidated edition 3.2:2013 that includes edition 3:2002, its Amendment 1:2006 and Amendment
2:2013.
– 10 – IEC 60335-2-96:2024 CMV © IEC 2024
3.5.102
heating unit
flexible sheet heating element equipped with means of connection to the supply and with
insulation surrounding live parts
Note 1 to entry: The heating unit can be partly or completely prefabricated.
3.5.103
modular heating unit
prefabricated assembly consisting of a heating unit and other materials to form a rigid
construction for mounting on a ceiling
3.5.104
storage heating application
use of heating units to heat thermal accumulating material
Note 1 to entry: The heat is discharged naturally, the heat output being varied by adjusting the energy input.
3.6 Definitions relating to parts of an appliance
3.6.101
electrode
conductive part incorporated in a flexible sheet heating element for supplying the heating
material
4 General requirement
This clause of Part 1 is applicable.
5 General conditions for the tests
This clause of Part 1 is applicable except as follows.
5.2 Replacement:
In general, eight samples are required for the tests.
The tests of 13.3 and of Clause 15 and Clause 16 are carried out on one sample.
The tests of 18.101 and of Clause 30 are carried out on one sample.
The test of 21.102 is carried out on two samples. One of these samples is also used for the test
of 22.101.
The test of 22.103 is carried out on one sample.
The remaining tests are carried out on the sixth sample. The other two samples are required
for incorporating into the test arrangement to create the necessary thermal environment.
NOTE 101 Additional samples can be necessary if tests have to be repeated.
Nine samples of modular heating units are necessary for the tests of 11.2.102.
Additional samples are necessary if the tests of 18.102 are carried out.
Additional samples can be necessary for testing different sizes of heating units.

The test of 22.105 is carried out on the same sample as that used for the test of 13.2.
Two samples of the additional layer of material, of sufficient a size necessary to cover the
heating unit, are required if the test of 21.104 is carried out.
NOTE 101 Additional samples can be necessary if tests have to be repeated or for testing different sizes of heating
units.
5.3 Addition:
The test of 22.105 is carried out after the test of 13.2.
5.6 Addition:
Thermostats sensitive to room air temperature or outdoor air temperature are short circuited.
However, the thermostat is not short circuited if it can be set so that it does not cycle.
5.10 Addition:
However, for flexible sheet heating elements that are cut on site, the tests are carried out
after connecting the supply leads and protecting the edges in accordance with the instructions.
5.101 Heating units intended to be installed in walls above a height of 2,3 m are subjected
to the tests for installation in ceilings.
6 Classification
This clause of Part 1 is applicable except as follows.
6.1 Addition:
It is not necessary to classify heating units need not be classified. However, if a heating unit
is classified, the relevant requirements apply.
6.2 Addition:
Heating units for installation in concrete or similar materials shall be at least IPX7.
Other heating units shall be at least IPX1.
7 Marking and instructions
This clause of Part 1 is applicable except as follows.
7.1 Modification:
Instead of the marking of rated power input or rated current the following applies:
– heating units shall be marked with their rated power input;
– flexible sheet heating elements without connection between adjacent elements shall be
individually marked with their rated power input;
– other flexible sheet heating elements shall be marked with their rated power input per
metre length.
Flexible sheet heating elements shall be marked with their maximum current if

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– the current can vary depending on the length of the flexible sheet heating element;
– other flexible sheet heating elements can be supplied through them.
Addition:
Flexible sheet heating elements shall be marked with:
– the indication of orientation, unless heating units are symmetrical;
– the intended installation (ceilings, walls between 0,2 m and 1,2 m and/or above 2,3 m, or
floors);
– the heating mode (direct heating or storage heating), unless intended for both modes.
If the heating unit is only intended for application in floors of concrete or similar materials, it
shall be marked with the symbol for installation in concrete or similar materials.
The marking shall be repeated at least once every 0,5 m of the flexible sheet heating element
or on every section that can be cut to form a heating unit.
Flexible sheet heating elements that can be cut on site and have to be cut at specified places
shall be marked appropriately.
Appliances with separate controls, without a control, or with detachable controls shall be
marked with the reference number or by other means of identification of the control.
7.6 Addition:
[symbol IEC 60417-6447
heating, direct ceiling heating
(2021-01)]
[symbol IEC 60417-6446
heating, direct floor heating
(2021-01)]
[symbol IEC 60417-6448
heating, floor storage heating
(2021-01)]
[symbol IEC 60417-6445
wall heating, wall
(2021-01)]
[symbol IEC 60417-6449 heating, installation in concrete
(2021-01)] or similar materials

These symbols are information signs and, except for the colours, the rules of ISO 3864-1 apply.

7.12.1 Addition:
Instructions shall be provided. They shall include
a) explanation of the marking and symbols, if necessary;
b) information for incorporating the heating units into the building, in particular the following:
• precautions to be taken to avoid damage during installation, such as dropping sharp
objects or stepping on the heating unit, or careless pouring of concrete;
• dimensions and distances to be taken into account;
• a statement that the heating units have to be separated from other heat sources such
as luminaires and chimneys;
• description of the fixing areas of the heating unit and the separate screen, if applicable;
• guidance on how to avoid air gaps between the flexible sheet heating element and the
screed of concrete floors;
• guidance on how to avoid damage to a flexible sheet heating element and its
terminations in timber constructions due to relative movement after installation;
• the lowest ambient temperature at which heating units may be installed are
recommended for installation;
• the minimum radius for bending the flexible sheet heating element, if applicable;
• a statement that heating units shall are not cross to be installed across expansion joints
of the building or structure;
• a statement to ensure that attachment of room fittings does not restrict heat emission
from heated areas.
Except for modular heating units, the instructions shall include the following:
• precautions to be taken to avoid creasing the flexible sheet heating element;
• a statement that the heating unit is not to be installed on irregular surfaces;
• a description of the intended orientation and a statement that the heating unit is to be
installed in this way (for heating units having non-symmetric construction);
c) a statement that the installation is to be in accordance with the national wiring rules. The
substance of the following information shall be included national wiring rules can apply for
the installation including the following:
• a statement that the heating units are to be supplied through a residual current device
(RCD) having a rated residual operating current not exceeding 30 mA. The RCD shall
not be of the time delayed type. Alternatively, except for installations in floors
surrounding swimming pools or walls below a height of 2,3 m, they may be supplied
through an isolating transformer. This statement is not required for class III heating
units and for applications in
– timber floors provided that the instructions for installation state that there is to be an
air gap between the heating unit and the floor;
– timber ceilings;
– floors of concrete or similar materials in dry locations (dry locations are areas outside
zone 3 as defined in IEC 60364-7-701) as long as the basic insulation and
additional electrical insulation each withstand the electric strength test of 16.3 for
reinforced insulation;
• how to connect heating units to the supply, giving the cross-sectional area of the leads,
if applicable;
• how to interconnect the heating units, giving the cross-sectional area of the leads, if
applicable;
• a statement that heating units shall be installed to avoid increasing the ambient
temperature of any existing electrical installation;

– 14 – IEC 60335-2-96:2024 CMV © IEC 2024
d) the maximum current allowed to flow through one heating unit when other units are supplied
through it or when the current can vary depending on its length;
e) list of controls, unless they are incorporated into the heating unit;
f) the maximum thermal resistance between the heating unit and the room;
g) the type of covering materials that are allowed to be used in conjunction with the heating
units with a statement that the advice of the manufacturer is to be requested before
materials other than those recommended are used; the thickness of covering materials,
which for floors shall be at least 5 mm;
h) characteristics of the thermal insulation that is to be inserted between separate heating
units installed to heat a floor and the ceiling below it;
i) characteristics of the thermal insulation that is to be inserted between separate heating
units installed to heat both sides of a wall;
j) specification of any adhesive to be used;
k) a statement that a label is to be fixed adjacent to the distribution board and that it has to
contain the locations of the heating units;
l) if the heating units are installed in a suspended ceiling, or are accessible from the roof
space, a statement that a label giving this information is to be fixed to the access point of
the ceiling;
m) in applications in timber floors, a statement indicating that heating units having basic
insulation only shall be covered by additional electrical insulation or supplied through an
isolating transformer.
NOTE 101 A summary of particular installation requirements for different applications is given in informative
Annex AA.
7.12.101 The instructions for applications in floors of concrete or similar materials, including
concrete or similar materials laid on a timber floor, or under tiles shall state that
a) a grid is to be installed above the heating unit. The grid is to
• be protected against corrosion but not electrically insulated;
• be electrically and mechanically equivalent to a steel grid having a mesh not more than
50 mm × 50 mm and a wire diameter of 1 mm, unless the grid covers
– class II heating units;
– heating units installed with additional electrical insulation;
• fully cover the heating unit including the fixing areas. It may can cover several heating
units;
• be connected to earth;
• be fitted with terminals suitable for the connection of two conductors each having a
nominal cross-sectional area of 2,5 mm ;
• be checked for electrical continuity during installation.
The grid is not required for
• class III heating units;
• class II heating units supplied through an isolating transformer;
• class II heating units that are installed in dry locations (dry locations are areas outside
zone 3 as defined in IEC 60364-7-701) and are supplied through a residual current
device (RCD);
• heating units installed in dry locations (dry locations are areas outside zone 3 as
defined in IEC 60364-7-701) if the basic insulation and additional electrical insulation
each withstand the electric strength test of 16.3 of reinforced insulation;
• heating units incorporating a metallic shield or braid having a resistance per unit length
equivalent to that of 0,5 mm copper wire;

b) when the heating units have been positioned, they must be covered with an additional layer
of material for mechanical protection. If the heating units are placed on concrete, a similar
layer is to be inserted between the heating unit and the concrete. Adjacent layers are to
overlap and be fixed to each other. The layer is to extend up each wall to the surface level
of the screed. These statements are not required if
• screened insulated heating wires are covered with a sheath complying with 21.103;
• the additional electrical insulation complies with the test of 21.102;
c) when heating units having basic insulation only, other than those supplied at safety
extra-low voltage, are provided with additional electrical insulation, this additional
insulation is to be placed directly on the heating unit;
d) class II heating units are to be installed at a distance of at least 30 mm from conductive
parts of the building, such as water pipes.
NOTE These instructions apply to applications where the concrete or similar material is laid on a timber floor.
7.12.102 The instructions for applications in metallic ceilings or metallic floors for heating
units with basic insulation only, other than those supplied at safety extra-low voltage, shall
state that
a) the flexible sheet heating element is to be fully covered by the ceiling or floor;
b) the metallic parts of the ceiling or floor are to be earthed. The instructions shall state that
they have to be fitted with terminals suitable for the connection of two conductors each
having a nominal cross-sectional area of 2,5 mm and explain how the connection to the
earthing terminal is to be made to ensure a low resistance. The statements regarding the
need for earthing are not required if it is stated that a layer of additional electrical insulation
is to be installed between the heating unit and the ceiling. If this insulation is not provided,
the name of the manufacturer and reference of the insulation shall be given.
7.12.103 The instructions for applications on floors where the heating units are to be covered
by tiles shall state that the heating units are to be covered by additional electrical insulation,
unless the heating units are class I, class II or class III.
7.12.104 The instructions for flexible sheet heating elements that can be cut on site shall
state that this work is only to be carried out by persons authorized by the manufacturer and
shall give information on how to
– cut the flexible sheet heating elements;
– protect the edges of the flexible sheet heating elements;
– connect the supply leads and to the interconnection leads and insulate the connections.
7.12.105 The instructions for heating units for storage heating applications shall specify
the rated charging period.
7.12.106 Unless heating units
– incorporate a metallic shield or braid having a resistance per unit length equivalent to that
of 0,5 mm copper wire; or
– are of class III; or
– consist of a base material on which metallically screened electrically insulated heating wires
are fixed and are for application in walls below a height of 1,2 m,
their instructions shall state that the heating units shall be of the type constructed with an
electrical conductive screen. The heating unit shall be installed so that the screen is towards
the covering material.
The instructions for heating units which are for application in walls below a height of 1,2 m and
with a separate electrical conductive screen shall state that the screen shall be placed between
the covering material and the heating unit.

– 16 – IEC 60335-2-96:2024 CMV © IEC 2024
The instructions for heating units which are for application in walls, shall state that the heating
unit shall be installed:
– between 0,2 m and 1,2 m above the floor; or
– above 2,3 m above the floor.
The instructions for heating units which are for application in walls, shall include the substance
of the following:
– the screen is to be connected to the earthing conductor of the fixed installation;
– if the heating unit is installed in an internal wall with the distance between the wall materials
less than 50 mm, the heating unit shall be installed so that the screen is towards the wall
covering material on both sides of the heating unit.
The instructions for heating units with detachable protection circuit shall give instructions
for their installation.
7.14 Modification:
The test with petroleum spirit is not carried out.
Addition:
If symbols are used relating to the intended installation or heating mode, the superimposed
rectangle shall have a height of at least 15 mm.
7.15 Modification:
Only the requirements for switches and controls are applicable.
7.101 A label that contains sufficient space for the locations of the heating units to be listed
by the installer shall be provided for each installation giving
– the name, tradem
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