IEC 60335-2-66:2025

IEC 60335-2-66 ®
Edition 3.0 2025-02
REDLINE VERSION
INTERNATIONAL
STANDARD
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters

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IEC 60335-2-66 ®
Edition 3.0 2025-02
REDLINE VERSION
INTERNATIONAL
STANDARD
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 97.100.10 ISBN 978-2-8327-0281-9

– 2 – IEC 60335-2-66:2025 RLV © IEC 2025
CONTENTS
FOREWORD . 3
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 General requirement . 8
5 General conditions for the tests . 8
6 Classification . 9
7 Marking and instructions . 9
8 Protection against access to live parts . 10
9 Starting of motor-operated appliances . 10
10 Power input and current . 10
11 Heating . 10
12 Void Charging of metal-ion batteries . 11
13 Leakage current and electric strength at operating temperature . 11
14 Transient overvoltages . 11
15 Moisture resistance . 11
16 Leakage current and electric strength . 11
17 Overload protection of transformers and associated circuits . 12
18 Endurance . 12
19 Abnormal operation . 12
20 Stability and mechanical hazards . 12
21 Mechanical strength . 12
22 Construction . 13
23 Internal wiring . 13
24 Components . 13
25 Supply connection and external flexible cords . 14
26 Terminals for external conductors . 15
27 Provision for earthing . 15
28 Screws and connections . 15
29 Clearances, creepage distances and solid insulation . 15
30 Resistance to heat and fire . 15
31 Resistance to rusting . 15
32 Radiation, toxicity and similar hazards . 15
Annexes . 17
Bibliography . 18

Figure 101 – Wood block . 16

Table 12 – Pull force and torque . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

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 this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
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the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 60335-2-66:2002+AMD1:2008+AMD2:2011 CSV. A
vertical bar appears in the margin wherever a change has been made. Additions are in
green text, deletions are in strikethrough red text.

– 4 – IEC 60335-2-66:2025 RLV © IEC 2025
IEC 60335-2-66 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 2002, Amendment 1:
2008 and Amendment 2:2011. 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, 19.4, 22.101);
c) clarification of requirements for remote operation (22.40, 22.49, 22.51).
The text of this International Standard is based on the following documents:
Draft Report on voting
61/7249/CDV 61/7356/RVC
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 water-bed heaters.
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.
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 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.
– 6 – IEC 60335-2-66:2025 RLV © IEC 2025
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.
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 that 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.

HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with the safety of electric water-bed heaters and their associated
control units, for household and similar purposes, their rated voltage being not more
than 250 V, including direct current (DC) supplied appliances.
Appliances not intended for normal household use, but that nevertheless may can be a source
of danger to the public, such as appliances intended to be used in hotels, are within the scope
of this standard.
As far as is practicable, this standard deals with the common hazards presented by appliances
that are encountered by all persons in and around the home. However, in general, it does not
take into account
– persons (including children) whose
• physical, sensory or mental capabilities; or
• lack of experience and knowledge
prevents them from using the appliance safely without supervision or instruction;
– children playing with the appliance.
NOTE 101 Attention is drawn to the fact that
– for appliances intended to be used in vehicles or on board ships or in aircraft, additional
requirements may can be necessary;
– in many countries, additional requirements are specified by the national health authorities,
the national authorities responsible for the protection of labour, the national water supply
authorities and similar authorities.
NOTE 102 This standard does not apply to appliances
– for medical purposes (IEC 60601 series);
– intended for immersion in water during use.
2 Normative references
This clause of Part 1 is applicable except as follows.
Addition:
ISO 2439, Flexible cellular polymeric materials – Determination of hardness (indentation
technique)
– 8 – IEC 60335-2-66:2025 RLV © IEC 2025
3 Terms and definitions
This clause of Part 1 is applicable except as follows.
3.1 Definitions relating to physical characteristics
3.1.9 Modification:
Replace the first paragraph with the following:
operation of the appliance after the heater has been installed under a water mattress, taking
into account the installation instructions
Note 101 to entry: See 5.10 for additional details of the appliance installation for normal operation.
3.5 Definitions relating to types of appliances
3.5.101
water-bed heater
appliance incorporating a heating element within an enclosure and intended for use under a
water mattress
Note 1 to entry: The appliance may can be contained in an envelope of the mattress.
Note 2 to entry: The appliance may can incorporate a thermostat having a sensing element that has to be is
positioned during installation.
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.
5.3 Addition:
The test of 21.101 is carried out immediately after the test of Clause 11.
5.10 Addition:
For normal operation, the appliance is supported by a wooden base that is consistent with the
size of the mattress. The top of the base consists of plywood approximately 13 mm thick and is
supported 150 mm above the floor by pinewood boards approximately 20 mm thick. The boards
are assembled to form a rectangular framework that includes a longitudinal and two transverse
members to produce six approximately equal sections.
The wooden base is completely covered by a sheet of open-cell polyether approximately 25 mm
thick. The polyether has the following composition:
+2
– cell count: 18 per cm;
+10 %
– specific mass: 30 kg/m ;
– hardness: 120 N to 170 N at 40 % impression, measured according to ISO 2439.
NOTE 101 This polyether sheet is omitted if the instructions state that the heater is unsuitable
for use on a soft support.
NOTE 102 Additional material is placed on the polyether sheet if this is stated in the instructions.
The heater, together with any control, is positioned on the polyether sheet. A piece of the bottom
layer of water mattress material, having dimensions 100 mm × 200 mm, is folded to form a
crease 50 mm × 200 mm. It is placed on the upper surface of the heater, parallel to the shortest
side and approximately in the centre of the longest side.
The mattress is placed over the heater, filled with water and completely covered by a similar
another piece of polyether sheet approximately 36 mm thick.
6 Classification
This clause of Part 1 is applicable except as follows.
6.1 Addition:
The rated voltage of class III appliances shall not exceed 24 V.
6.2 Addition:
Parts of the appliance, other than those of class III, that are intended to be placed under the
water mattress shall be at least IPX7.
7 Marking and instructions
This clause of Part 1 is applicable except as follows.
7.1 Addition:
The appliance shall be marked with the substance of the following:
– read the instructions carefully;
– check that the heater, the mattress and any envelope are laid flat and without folds before
filling the mattress with water;
– place the heater centrally under the mattress so that it does not project from the sides of
the mattress enclosure;
– the support under the heater is to be flat, continuous and without sharp edges;
– use only to heat water-beds;
– this side up, if applicable.
The appliance shall be marked with the model or type reference of a detachable control unit,
if applicable, intended for use with the appliance.
7.12 Addition:
The instructions shall include the substance of the following:
– the heater is only to be used with the type of detachable control unit that is marked on the
appliance, if applicable;
– the appliance is not intended for use in hospitals;
– the appliance is intended only to heat water-beds;
– sharp objects such as needles and pins must not be inserted in the appliance;
– bedding is not to come into contact with the heater.

– 10 – IEC 60335-2-66:2025 RLV © IEC 2025
The instructions for appliances other than those with a polarized plug shall describe the
orientation of the plug in the socket-outlet of class II appliances provided with a metal screen
to minimize the capacitive leakage current and the electrostatic field. The means of checking
the orientation shall be given specified.
NOTE 101 This does not apply to appliances having a polarized plug.
7.12.1 Addition:
The installation instructions shall include the substance of the following:
– the details of the installation of the heater and its control. In particular, details shall be given
regarding the correct positioning and installation of any temperature sensing element of the
control unit, to ensure that it does not easily slip out of position;
– the minimum dimensions of the water mattress and the minimum depth of water with which
it is to be filled;
– details of any additional supporting material required if the heater is installed on a soft
support, or a statement that the heater is unsuitable for such installation.
7.101 Detachable control units shall be marked with:
– rated voltage or rated voltage range in volts;
– symbol for nature of supply, unless the rated frequency is marked;
– name, trade mark or identification mark of the manufacturer or responsible vendor;
– model or type reference;
– identification of the relevant water-bed heater.
Compliance is checked by inspection.
8 Protection against access to live parts
This clause of Part 1 is applicable.
9 Starting of motor-operated appliances
This clause of Part 1 is not applicable.
10 Power input and current
This clause of Part 1 is applicable.
11 Heating
This clause of Part 1 is applicable except as follows.
11.2 Replacement:
The appliance is installed as specified for normal operation.
11.3 Addition:
The temperature rise of the surface of the water-bed heater and the surface temperature of
the mattress are determined by means of fine-wire thermocouples attached to oxidized copper
or brass plates measuring 65 mm × 65 mm × 0,5 mm.

11.4 Addition:
Thermostats are short-circuited if their sensing elements are not fixed in relation to the heater
after installation.
NOTE 101 Sensing elements are not considered to be fixed if they are positioned outside the enclosure of the
heater and without provision for fixing.
11.7 Modification:
Replace the first paragraph with the following:
The appliance is operated until steady conditions are established.
11.8 Addition:
The temperature rise of the surface of the water-bed heater shall not exceed 35 K except under
the folded material where the limit is 60 K.
11.101 The appliance shall operate without risk of heat-stroke to the user.
Compliance is checked by the following test.
The appliance is operated as specified in 11.1 to 11.7 except that thermostats are not short-
circuited. Controls are set in the lowest position.
The temperature of the upper surface of the water mattress shall not exceed 37 °C.
12 Void Charging of metal-ion batteries
This clause of Part 1 is applicable.
13 Leakage current and electric strength at operating temperature
This clause of Part 1 is applicable except as follows.
13.2 ModificationAddition:
The leakage current of class II appliances provided with a metal screen connected to live
parts shall not exceed 0,25 mA when the selector switch is in one position and 0,75 mA in the
other position.
14 Transient overvoltages
This clause of Part 1 is applicable.
15 Moisture resistance
This clause of Part 1 is applicable.
16 Leakage current and electric strength
This clause of Part 1 is applicable.

– 12 – IEC 60335-2-66:2025 RLV © IEC 2025
17 Overload protection of transformers and associated circuits
This clause of Part 1 is applicable.
18 Endurance
This clause of Part 1 is not applicable.
19 Abnormal operation
This clause of Part 1 is applicable except as follows.
19.2 Addition:
The test is carried out without the folded water mattress material.
The water mattress is empty.
19.4 Addition:
NOTE 101 This test is not carried out when the thermostat is short-circuited during the test of
Clause 11.
19.13 Addition:
The temperature rise of the surface of the water-bed heater shall not exceed 100 K.
The tests shall not affect impair the degree of protection of the appliance against harmful
ingress of water.
19.101 The appliance is operated under the conditions of Clause 11 but without the folded
water mattress material. The water-bed heater is positioned so that it extends outside the
waterbed envelope by 10 cm along its longest side and it is supplied at rated power input.
The temperature rise of the surface of the water-bed heater that extends beyond the mattress
enclosure shall not exceed 65 K but a first overshoot up to 95 K is allowed.
20 Stability and mechanical hazards
This clause of Part 1 is applicable.
21 Mechanical strength
This clause of Part 1 is applicable except as follows.
21.101 Appliances provided with a flexible support for the heater shall withstand the
mechanical stresses that the heater may can be subjected to during normal use.
Compliance is checked by the following test.
The appliance is operated as specified in Clause 11 but without the covering sheet of polyether.

The water mattress is subjected to a downward force of 950 N ± 40 N by means of the wood
block shown in Figure 101 that is positioned in the most unfavourable place. The force is applied
25 000 times at a rate of approximately 30 times per minute.
During the test, the power input shall not deviate from the power input measured at the start of
the test by more than +5 % and –10 %.
After the test, the heater shall not be damaged to such an extent that compliance with this
standard is impaired.
22 Construction
This clause of Part 1 is applicable except as follows.
22.40 Addition:
These appliances are not considered to be appliances that could give rise to a hazard when
operated continuously, automatically or remotely.
22.49 Not applicable.
22.51 Not applicable.
22.101 Class II appliances having a metal screen connected to live parts and without a
polarized plug shall incorporate a means to indicate that the plug has been inserted in the
socket outlet so that the leakage current is minimum minimized.
Compliance is checked by inspection and by manual test.
NOTE 1 This requirement does not apply to appliances having a polarized plug.
NOTE 2 The indicating means may can require a manual action. A light-emitting diode that glows when a surface
is touched is an example of a device that can be used.
22.102 Class I appliances having an earthed metal screen shall incorporate supplementary
insulation between the screen and the accessible surfaces.
Compliance is checked by inspection.
23 Internal wiring
This clause of Part 1 is applicable except as follows.
23.5 Addition:
Natural rubber shall not be used for the insulation of internal wiring.
24 Components
This clause of Part 1 is applicable except as follows.
24.1.4 Modification:
The number of cycles of operation for voltage-maintained non-self-resetting thermal cut-outs
is increased to 10 000.
– 14 – IEC 60335-2-66:2025 RLV © IEC 2025
24.2 Modification:
Delete "switches, automatic controls," from the first dashed item.
Addition:
Appliances may be fitted with switches and control units in flexible cords.
24.101 Thermal cut-outs shall not be self-resetting thermal cut-outs.
Compliance is checked by inspection.
25 Supply connection and external flexible cords
This clause of Part 1 is applicable except as follows.
25.5 Addition:
Type Z attachment is allowed.
25.7 Modification:
Light polyvinyl chloride sheathed cords are allowed regardless of the mass of the appliance.
Delete "for appliances having a mass not exceeding 3 kg" from the first bullet under the third
and fourth dashed items.
25.15 Modification:
Instead of marking the cord at a distance of 20 mm, the cord is marked as close as possible to
the cord anchorage.
Instead of the pull force and torque specified in Table 12, the following applies:
– cord anchorage of the interconnection cord:
• pull force: 100 N;
• torque: 0,1 Nm
– cord anchorage of the supply cord:
• pull force: 60 N;
• torque: 0,1 Nm.
In the fourth paragraph, replace "at a distance of approximately 20 mm from the cord
anchorage" with "at the cord anchorage".
Replace Table 12 with the following:
Table 12 – Pull force and torque
Cord usage Pull force Torque
N Nm
Interconnection cords 100 0,1
Supply cords 60 0,1
25.23 Addition:
The insulation of interconnection cords shall be at least equivalent to that of ordinary polyvinyl
chloride sheathed flexible cord (code designation 60227 IEC 53).
26 Terminals for external conductors
This clause of Part 1 is applicable.
27 Provision for earthing
This clause of Part 1 is applicable.
28 Screws and connections
This clause of Part 1 is applicable.
29 Clearances, creepage distances and solid insulation
This clause of Part 1 is applicable except as follows.
29.3 Addition:
If the insulation is in more than one layer, it shall not be accessible after installation of the
heater.
30 Resistance to heat and fire
This clause of Part 1 is applicable except as follows.
30.1 Addition:
The test is not applied to the enclosure of the heater.
30.2.2 Not applicable.
31 Resistance to rusting
This clause of Part 1 is applicable.
32 Radiation, toxicity and similar hazards
This clause of Part 1 is applicable.

– 16 – IEC 60335-2-66:2025 RLV © IEC 2025
Dimensions in millimetres
+
Key
A point of application of the load
Figure 101 – Wood block
Annexes
The annexes of Part 1 are applicable.

– 18 – IEC 60335-2-66:2025 RLV © IEC 2025
Bibliography
The Bibliography of Part 1 is applicable except as follows.
Addition:
ISO 13732-1, Ergonomics of the thermal environment – Methods for the assessment of human
responses to contact with surfaces – Part 1: Hot surfaces
IEC 60601 (all parts), Medical electrical equipment

___________
IEC 60335-2-66 ®
Edition 3.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters

Appareils électrodomestiques et analogues – Sécurité –
Partie 2-66: Exigences particulières pour les dispositifs de chauffage pour
matelas à eau
– 2 – IEC 60335-2-66:2025 © IEC 2025
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 General requirement . 7
5 General conditions for the tests . 7
6 Classification . 8
7 Marking and instructions . 8
8 Protection against access to live parts . 9
9 Starting of motor-operated appliances . 9
10 Power input and current . 9
11 Heating . 9
12 Charging of metal-ion batteries . 10
13 Leakage current and electric strength at operating temperature . 10
14 Transient overvoltages . 10
15 Moisture resistance . 10
16 Leakage current and electric strength . 10
17 Overload protection of transformers and associated circuits . 11
18 Endurance . 11
19 Abnormal operation . 11
20 Stability and mechanical hazards . 11
21 Mechanical strength . 11
22 Construction . 12
23 Internal wiring . 12
24 Components . 12
25 Supply connection and external flexible cords . 13
26 Terminals for external conductors . 13
27 Provision for earthing . 13
28 Screws and connections . 14
29 Clearances, creepage distances and solid insulation . 14
30 Resistance to heat and fire . 14
31 Resistance to rusting . 14
32 Radiation, toxicity and similar hazards . 14
Annexes . 16
Bibliography . 17

Figure 101 – Wood block . 15

Table 12 – Pull force and torque . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

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 this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its tec
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