IEC 60601-2-35:2020

IEC 60601-2-35 ®
Edition 2.0 2020-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Medical electrical equipment –
Part 2-35: Particular requirements for the basic safety and essential performance
of heating devices using blankets, pads or mattresses and intended for heating
in medical use
Appareils électromédicaux –
Partie 2-35: Exigences particulières pour la sécurité de base et les performances
essentielles des dispositifs de réchauffage utilisant des couvertures, des
coussins ou des matelas et destinés au réchauffage des patients en usage
médical
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IEC 60601-2-35 ®
Edition 2.0 2020-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Medical electrical equipment –

Part 2-35: Particular requirements for the basic safety and essential

performance of heating devices using blankets, pads or mattresses and

intended for heating in medical use

Appareils électromédicaux –
Partie 2-35: Exigences particulières pour la sécurité de base et les performances

essentielles des dispositifs de réchauffage utilisant des couvertures, des

coussins ou des matelas et destinés au réchauffage des patients en usage

médical
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 11.040.01; 11.140 ISBN 978-2-8322-1015-8

– 2 – IEC 60601-2-35:2020 © IEC 2020
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
201.1 Scope, object and related standards . 8
201.2 Normative references . 10
201.3 Terms and definitions. 10
201.4 General requirements . 13
201.5 General requirements for testing ME EQUIPMENT . 14
201.6 Classification of ME EQUIPMENT and ME SYSTEMS . 14
201.7 ME EQUIPMENT identification, marking and documents . 14
201.8 Protection against electrical HAZARDS from ME EQUIPMENT . 18
201.9 Protection against MECHANICAL HAZARDS of ME EQUIPMENT and ME SYSTEMS . 24
201.10 Protection against unwanted and excessive radiation HAZARDS . 26
201.11 Protection against excessive temperatures and other HAZARDS . 26
201.12 Accuracy of controls and instruments and protection against hazardous
outputs . 28
201.13 HAZARDOUS SITUATIONS and fault conditions for ME EQUIPMENT . 33
201.14 PROGRAMMABLE ELECTRICAL MEDICAL SYSTEMS (PEMS) . 38
201.15 Construction of ME EQUIPMENT . 38
201.16 ME SYSTEMS . 42
201.17 Electromagnetic compatibility of ME EQUIPMENT and ME SYSTEMS . 42
202 ELECTROMAGNETIC DISTURBANCES – Requirements and tests . 43
208 General requirements, tests and guidance for ALARM SYSTEMS IN MEDICAL
ELECTRICAL EQUIPMENT and MEDICAL ELECTRICAL SYSTEMS . 43
210 * Requirements for the development of PHYSIOLOGIC CLOSED-LOOP CONTROLLERS . 43
Annexes . 44
Annex D (informative) Symbols on marking . 44
Annex AA (informative) Particular guidance and rationale . 45
Annex BB (normative) Determination of the LAGGING MATERIAL . 57
Annex CC (normative) * Determination of heat transfer towards the PATIENT . 58
Annex DD (normative) * Determination of heat transfer away from the PATIENT . 60
Annex EE (normative) CONDITIONS OF ADEQUATE HEAT DISCHARGE . 61
Annex FF (normative) Test procedure for maximum CONTACT SURFACE TEMPERATURE
for FORCED AIR DEVICES . 62
Annex GG (normative) Test procedure for maximum CONTACT SURFACE TEMPERATURE
for FORCED AIR DEVICES under SINGLE FAULT CONDITION. 64
Annex HH (normative) Safety test procedure for average CONTACT SURFACE
TEMPERATURE for FORCED AIR DEVICES . 65
Bibliography . 67
Index of defined terms used in this document . 69

Figure 201.101 – Positioning of temperature sensors on the contact surface of the
heated area of a HEATING DEVICE (see 201.12.4.101 and 201.12.4.105) . 11

Figure 201.102 – Example of the positioning of temperature sensors on the contact
surface of the heated areas of a HEATING DEVICE having more than one separately
heated area . 12
Figure 201.103 – Apparatus for the spark ignition test . 22
Figure 201.104 – Ramp for the impact test on PADS . 24
Figure 201.105 – Partial covering conditions . 26
Figure 201.106 – Method of folding BLANKETS . 35
Figure 201.107 – Examples of folds . 37
Figure 201.108 – Positions of a BLANKET for the RUCK-RESISTANCE test. 42
Figure AA.1 – Illustration of the main requirements of this document . 45
Figure HH.1 – Sensor locations – Average CONTACT SURFACE TEMPERATURE . 66

Table 201.101 – * Additional ESSENTIAL PERFORMANCE requirements . 14
Table 201.102 – Temperature limits in dependency to time . 39

– 4 – IEC 60601-2-35:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-35: Particular requirements for the basic safety
and essential performance of heating devices using blankets,
pads or mattresses and intended for heating in medical use

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
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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 60601-2-35 has been prepared by IEC technical committee 62D:
Electromedical equipment, of IEC technical committee 62: Electrical equipment in medical
practice.
This second edition cancels and replaces IEC 80601-2-35 published in 2009 and
Amendment 1:2016.
The text of this particular standard is based on the following documents:
FDIS Report on voting
62D/1765/FDIS 62D/1777/RVD
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this document, the following print types are used:
– requirements and definitions: roman type;
– test specifications: italic type;
– informative material appearing outside of tables, such as notes, examples and references: in smaller type.
Normative text of tables is also in a smaller type;
– TERMS DEFINED IN CLAUSE 3 OF THE GENERAL STANDARD, IN THIS PARTICULAR STANDARD OR AS
NOTED: SMALL CAPITALS.
In referring to the structure of this document, the term
– "clause" means one of the seventeen numbered divisions within the table of contents,
inclusive of all subdivisions (e.g. Clause 7 includes subclauses 7.1, 7.2, etc.);
– "subclause" means a numbered subdivision of a clause (e.g. 7.1, 7.2 and 7.2.1 are all
subclauses of Clause 7).
References to clauses within this document are preceded by the term "Clause" followed by the
clause number. References to subclauses within this particular standard are by number only.
In this document, the conjunctive "or" is used as an "inclusive or" so a statement is true if any
combination of the conditions is true.
The verbal forms used in this document conform to usage described in Clause 7 of the ISO/IEC
Directives, Part 2. For the purposes of this document, the auxiliary verb:
– "shall" means that compliance with a requirement or a test is mandatory for compliance with
this document;
– "should" means that compliance with a requirement or a test is recommended but is not
mandatory for compliance with this document;
– "may" is used to describe a permissible way to achieve compliance with a requirement or
test.
An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title
indicates that there is guidance or rationale related to that item in Annex AA.
A list of all parts of the 60601 International Standard, published under the general title Medical
electrical equipment, can be found on the IEC website.

– 6 – IEC 60601-2-35:2020 © IEC 2020
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
NOTE The attention of users of this document is drawn to the fact that equipment manufacturers and testing
organizations may 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 committees that the content of this publication be adopted for
implementation nationally not earlier than 3 years from the date of publication.

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 publication using a colour printer.

INTRODUCTION
The minimum safety requirements specified in this particular standard are considered to provide
for a practical degree of safety in the operation for HEATING DEVICES using BLANKETS, PADS or
MATTRESSES and intended for heating in medical use.
While K (degree Kelvin) is the recognized unit and symbol for absolute temperature and
temperature difference, °C has been used throughout this document because all measurements
are commonly made using equipment marked with the Celsius temperature scale.

– 8 – IEC 60601-2-35:2020 © IEC 2020
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-35: Particular requirements for the basic safety
and essential performance of heating devices using blankets,
pads or mattresses and intended for heating in medical use

201.1 Scope, object and related standards
Clause 1 of the general standard applies, except as follows:
201.1.1 * Scope
Replacement:
This part of 60601 International Standard applies to the BASIC SAFETY and ESSENTIAL
PERFORMANCE of HEATING DEVICES using BLANKETS, PADS or MATTRESSES in medical use, also
referred to as ME EQUIPMENT. HEATING DEVICES intended to prewarm a bed are included in the
scope of this document.
If a clause or subclause is specifically intended to be applicable to ME EQUIPMENT only, or to
ME SYSTEMS only, the title and content of that clause or subclause will say so. If that is not the
case, the clause or subclause applies both to ME EQUIPMENT and to ME SYSTEMS, as relevant.
If a clause or subclause is specifically intended to be applicable to a specifically defined type
of ME EQUIPMENT, as is the case with FORCED AIR DEVICES, then the title and content of that
clause or subclause will say so. If that is not the case, the clause or subclause applies both to
ME EQUIPMENT and to ME SYSTEMS, as relevant.
HAZARDS inherent in the intended physiological function of ME EQUIPMENT or ME SYSTEMS within
the scope of this document are not covered by specific requirements in this document, except
in 7.2.13 and 8.4.1 of the general standard.
NOTE See also 4.2 of the general standard.
This document does not apply to:
– HEATING DEVICES intended for physiotherapy;
– INFANT RADIANT WARMERS; for information, see IEC 60601-2-21 [1] ;
– INFANT INCUBATORS; for information, see IEC 60601-2-19 [2];
– INFANT TRANSPORT INCUBATORS, for information, see IEC 60601-2-20 [3];
– cooling devices.
_____________
The general standard is IEC 60601-1:2005 and IEC 60601-1:2005/AMD1:2012, Medical electrical equipment –
Part 1: General requirements for basic safety and essential performance.
Figures in square brackets refer to the Bibliography.

201.1.2 Object
Replacement:
The object of this particular standard is to establish particular BASIC SAFETY and ESSENTIAL
PERFORMANCE requirements, which minimize HAZARDS to PATIENTS, and OPERATORS for HEATING
DEVICES using BLANKETS, PADS or MATTRESSES and intended for heating in medical use and to
specify tests for demonstrating compliance with these requirements.
201.1.3 Collateral standards
Addition:
This particular standard refers to those applicable collateral standards that are listed in Clause
2 of the general standard and Clause 201.2 of this particular standard.
IEC 60601-1-2:2014, IEC 60601-1-8:2006 and IEC 60601-1-8:2006/AMD1:2012, and
IEC 60601-1-10:2007 and IEC 60601-1-10:2007/AMD1:2013 apply as modified in Articles 202,
208 and 210 respectively. IEC 60601-1-3 does not apply. All other published collateral
standards in the IEC 60601-1 series apply as published.
201.1.4 Particular standards
Replacement:
In the IEC 60601 series, particular standards may modify, replace or delete requirements
contained in the general standard and collateral standards as appropriate for the particular
ME EQUIPMENT under consideration, and may add other BASIC SAFETY and ESSENTIAL
PERFORMANCE requirements.
A requirement of a particular standard takes priority over the general standard.
For brevity, IEC 60601-1:2005 and IEC 60601-1:2005/AMD1:2012 are referred to in this
particular standard as the general standard. Collateral standards are referred to by their
document number.
The numbering of clauses and subclauses of this document corresponds to that of the general
standard with the prefix "201" (e.g. 201.1 in this document addresses the content of Clause 1
of the general standard) or applicable collateral standard with the prefix "20x" where x is the
final digit(s) of the collateral standard document number (e.g. 202.4 in this document addresses
the content of Clause 4 of the IEC 60601-1-2 collateral standard, 203.4 in this document
addresses the content of Clause 4 of the IEC 60601-1-3 collateral standard, etc.). The changes
to the text of the general standard and applicable collateral standards are specified by the use
of the following words:
"Replacement" means that the clause or subclause of the general standard or applicable
collateral standard is replaced completely by the text of this particular standard.
"Addition" means that the text of this particular standard is additional to the requirements of the
general standard or applicable collateral standard.
"Amendment" means that the clause or subclause of the general standard or applicable
collateral standard is amended as indicated by the text of this particular standard.

– 10 – IEC 60601-2-35:2020 © IEC 2020
Subclauses, figures or tables which are additional to those of the general standard are
numbered starting from 201.101. However due to the fact that definitions in the general standard
are numbered 3.1 through 3.147, additional definitions in this document are numbered
beginning from 201.3.201. Additional annexes are lettered AA, BB, etc., and additional items
aa), bb), etc.
Subclauses, figures or tables which are additional to those of a collateral standard are
numbered starting from 20x, where "x" is the number of the collateral standard, e.g. 202 for
IEC 60601-1-2, 203 for IEC 60601-1-3, etc.
The term "this document" is used to make reference to the general standard, any applicable
collateral standards and this particular standard taken together.
Where there is no corresponding clause or subclause in this particular standard, the clause or
subclause of the general standard or applicable collateral standard, although possibly not
relevant, applies without modification; where it is intended that any part of the general standard
or applicable collateral standard, although possibly relevant, is not to be applied, a statement
to that effect is given in this particular standard.
201.2 Normative references
NOTE Informative references are listed in the Bibliography.
Clause 2 of the general standard applies, except as follows:
Addition:
IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60601-1:2005/AMD1:2012
IEC 60601-1-10:2007, Medical electrical equipment – Part 1-10: General requirements for basic
safety and essential performance – Collateral Standard: Requirements for the development of
physiologic closed-loop controllers
IEC 60601-1-10:2007/AMD1:2013
Replacement:
IEC 60384-14:2013, Fixed capacitors for use in electronic equipment – Part 14: Sectional
specification – Fixed capacitors for electromagnetic interference suppression and connection
to the supply mains
IEC 60384-14:2013/AMD1:2016
IEC 60601-1-2:2014, Medical electrical equipment – Part 1-2: General requirements for basic
safety and essential performance – Collateral standard: Electromagnetic disturbances –
Requirements and tests
201.3 Terms and definitions
For the purposes of this document, the terms and definitions specified in IEC 60601-1:2005 and
IEC 60601-1:2005/AMD1:2012, and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE An index of defined terms used in this document is found beginning on page 69.
Addition:
201.3.201.1
BLANKET
APPLIED PART of HEATING DEVICE, which can be folded, for use
under or over a PATIENT
201.3.201.2
BLANKET
APPLIED PART of HEATING DEVICE intended to be used with a CONTROLLER
PATIENT
to transfer thermal energy to all or part of the body of a
201.3.202
CONDITIONS OF ADEQUATE HEAT DISCHARGE
conditions achieved when a HEATING DEVICE is supported and covered as specified in Annex EE
201.3.203.1
CONTACT SURFACE TEMPERATURE
FORCED AIR DEVICES> temperature T at the reference point of the heated APPLIED
R
PART
Note 1 to entry: See Figures 201.101 and 201.102.
Note 2 to entry: The CONTACT SURFACE TEMPERATURE for FORCED AIR DEVICES is measured by the test methods
described in Annexes FF, GG and HH.

Key
T CONTACT SURFACE TEMPERATURE reference point on the contact surface
R
Some HEATING DEVICES may have unheated areas shown in the following figures as:
Figure 201.101 – Positioning of temperature sensors on the contact surface
of the heated area of a HEATING DEVICE
(see 201.12.4.101 and 201.12.4.105)

– 12 – IEC 60601-2-35:2020 © IEC 2020

The temperature at the centre point of any one of the heated areas closest to the centre of the HEATING DEVICE (in the
example shown above 2, 3, 6, or 7) is treated as T .
R
Figure 201.102 – Example of the positioning of temperature sensors
on the contact surface of the heated areas of a HEATING DEVICE having
more than one separately heated area
201.3.203.2
CONTACT SURFACE TEMPERATURE
< FORCED AIR DEVICES> temperature resulting from the heat transferred to a target surface by
APPLIED PART
the
201.3.204
CONTROLLER
part of a HEATING DEVICE intended to supply and control thermal energy to a BLANKET, PAD or
MATTRESS
Note 1 to entry: This includes the HOSE, if present.
201.3.205
FORCED AIR DEVICE
HEATING DEVICE that uses air as the heat transfer medium to warm a PATIENT and is comprised
of a CONTROLLER and a BLANKET
201.3.206
FREE HOSING
hazardous practice or condition of using the CONTROLLER without a BLANKET
201.3.207
HEATING DEVICE
ME EQUIPMENT intended to supply heat to the whole or part of the body of a PATIENT by means
of heated BLANKETS, PADS, or MATTRESSES
201.3.208
HIGH HEAT TRANSFER
thermal characteristic of a HEATING DEVICE as determined according to Annex CC or Annex DD
201.3.209
HOSE
component of the CONTROLLER that is the conduit for the heat transfer medium to and/or from
the BLANKET, PAD or MATTRESS
201.3.210
INFANT
PATIENT up to the age of three months and with a weight less than 10 kg
201.3.211
LAGGING MATERIAL
polyurethane or polystyrene insulation material used in the test methods of this specification to
assist in the determination of temperature
Note 1 to entry: Specifications for LAGGING MATERIAL are given in Annexes BB and FF.
201.3.212
LOW HEAT TRANSFER
thermal characteristic of a HEATING DEVICE as determined according to Annex CC or Annex DD
201.3.213
MATTRESS
APPLIED PART of a HEATING DEVICE, which provides resilient support to the whole body of a
PATIENT
201.3.214
NOZZLE
end of the HOSE that connects to the BLANKET, PAD or MATTRESS
201.3.215
OVER-BLANKET
BLANKET designed to be used over a PATIENT
201.3.216
PAD
APPLIED PART of HEATING DEVICE, which can be bent but not folded
201.3.217
RUCK
unintended fold in a normally even surface
201.3.218
RUCK-RESISTANT BLANKET
BLANKET having a construction such that RUCKING of the flexible part is unlikely
201.3.219
UNDER-BLANKET
BLANKET designed to be used under a PATIENT
201.4 General requirements
Clause 4 of the general standard applies except as follows:
201.4.3 ESSENTIAL PERFORMANCE
Addition:
201.4.3.101 Additional requirements for ESSENTIAL PERFORMANCE
Additional ESSENTIAL PERFORMANCE requirements are found in the subclauses listed in
Table 201.101.
– 14 – IEC 60601-2-35:2020 © IEC 2020
Table 201.101 – * Additional ESSENTIAL PERFORMANCE requirements
Requirement Subclause
ESSENTIAL PERFORMANCE requirement 1 201.12.4.104 or generation of a TECHNICAL ALARM
CONDITION in compliance with 201.12.3.102

201.4.5 Alternative RISK CONTROL measures or test methods for me equipment or me
systems
Addition:
This particular standard specifies safety requirements for HEATING DEVICES using BLANKETS,
PADS or MATTRESSES, but alternate methods of compliance with a specific clause or subclause
by demonstrating equivalent safety will not be judged non-compliant if the MANUFACTURER has
demonstrated in his RISK MANAGEMENT FILE that the RISKS presented by the HAZARDS are of an
acceptable level when weighed against the benefits of treatment using the device.
Additional subclause:
201.4.101 Combination of equipment
For equipment which combines several heat sources, the safety requirements of other relevant
particular standards shall be considered. Further, the safety requirements of this particular
standard shall be fulfilled with the combination of the other equipment, which is approved by
the MANUFACTURER as stated in the instructions for use according to Clause 16 of the general
standard (ME SYSTEMS).
201.5 General requirements for testing ME EQUIPMENT
Clause 5 of the general standard applies.
201.6 Classification of ME EQUIPMENT and ME SYSTEMS
Clause 6 of the general standard applies, except as follows:
201.6.2 Protection against electric shock
Replacement of the last paragraph with the following new paragraph:
HEATING DEVICES shall have TYPE BF APPLIED PARTS or TYPE CF APPLIED PARTS.
201.7 ME EQUIPMENT identification, marking and documents
Clause 7 of the general standard applies, except as follows:

201.7.2.1 Minimum requirements for marking on ME EQUIPMENT and on
interchangeable parts
Addition:
201.7.2.1.101 * Additional minimum requirements for marking on ME EQUIPMENT and on
interchangeable parts
201.7.2.1.101.1 HEATING DEVICES (other than for FORCED AIR DEVICES)
A HEATING DEVICE shall be marked as follows:
NORMAL USE, whether:
a) to indicate how it is intended to be positioned in
– over the PATIENT;
PATIENT;
– under the
– directly in contact with the PATIENT;
PATIENT by an intermediate layer, or layers (for example by a water-
– separated from the
bed, other type of MATTRESS, or bedclothes);
– it has to be used flat (that is without creases), or whether it can be wrapped around the
PATIENT;
b) to warn against possible HAZARDOUS SITUATIONS from penetration by sharp objects;
c) to warn against possible HAZARDOUS SITUATIONS from folding or methods of storage, other
MANUFACTURER;
than those specified by the
d) to warn against the possibility of a HAZARDOUS SITUATION if a partial covering is caused by
pillows or other items having good thermal insulation being laid over part of the HEATING
DEVICE;
e) to specify, in the case of liquid-filled MATTRESSES intended to be used above a PAD, the
minimum amount of liquid to which the MATTRESS should be filled, and a warning that if this
minimum amount is not present a PATIENT could suffer a burn;
f) to specify, in the case of a HEATING DEVICE supplied or controlled by an external unit, that
the HEATING DEVICE shall only be used with the external unit specified by the MANUFACTURER
of the HEATING DEVICE.
201.7.2.1.101.2 CONTROLLERS
A CONTROLLER for FORCED AIR DEVICES shall be marked as follows.
HOSE shall be marked within 15 cm of the NOZZLE to caution that the NOZZLE needs to
a) The
be connected to a BLANKET. The following statement and the safety sign ISO 7010-M002
(see IEC 60601-1:2005, Table D.2, safety sign 10) shall accompany the "no FREE HOSING"
safety sign shown in Annex D of this particular standard:
"CAUTION! HOSE NOZZLE SHALL be connected to a compatible forced air BLANKET or thermal
injury may occur."
b) A caution that allowing the HOSE to contact the PATIENT can lead to thermal injury, if
appropriate.
c) A warning against using the device distal to arterial cross clamping and that non-observance
can lead to thermal injury.
201.7.2.1.101.3 * Temperature sensors
A temperature sensor which is designed to be attached to or inserted into a PATIENT shall have
its intended use identified clearly and unambiguously on or adjacent to the sensor.

– 16 – IEC 60601-2-35:2020 © IEC 2020
201.7.2.1.101.4 APPLIED PARTS (for other than FORCED AIR DEVICES) with a large
unheated border
For an APPLIED PART having an unheated border wider than 30 mm around the heated area, and
where the requirements of 201.12.4.101 are not satisfied, the outer boundary of the heated area
shall be marked on both sides of the APPLIED PART.
201.7.4.2 Control devices
Addition:
201.7.4.2.101 Additional requirements for control devices
NOTE See also 201.12.
Where provided, on ME EQUIPMENT other than FORCED AIR DEVICES, a control for setting the
CONTACT SURFACE TEMPERATURE of a HEATING DEVICE shall indicate the temperature in intervals
not greater than 1 °C (see also 201.12.1.101).
For FORCED AIR DEVICES, each heated temperature control position shall be marked in
degrees C. Such marking shall be CLEARLY LEGIBLE.
201.7.9.2.2 Warning and safety notices
Addition:
201.7.9.2.2.101 Additional requirements for warning and safety notices
The instructions for use shall additionally contain the following:
a) a strong recommendation that the surface of the HEATING DEVICE should be checked for
freedom from mechanical damage prior to each application;
b) an indication for the use of parts of HEATING DEVICES which are intended to be used together;
c) statements, details and warnings on the use of the HEATING DEVICE in combination with other
heat sources, if applicable;
d) a warning statement that the use of materials of good thermal conductivity, such as water,
gel and similar substances, with the HEATING DEVICE not switched on can decrease the
temperature of the body of a PATIENT;
e) a warning statement regarding the RISK of electrical shock, burns or electromagnetic
interference with use of high frequency (HF) surgical instruments or endocardial catheters
while a HEATING DEVICE is in use, if applicable;
f) a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
g) a statement that means for drainage of liquid from a liquid-filled HEATING DEVICE is required
(see also 201.11.6.5.101);
h) a warning that a means for retaining a PATIENT either on or under a HEATING DEVICE may
need to be used and that the means for retaining a PATIENT should not block the fluid
pathways of the HEATING DEVICE;
i) a warning that warming transdermal medications (patches) can increase drug delivery,
resulting in possible HARM to the PATIENT;
j) a statement that the HEATING DEVICE contains an ALARM SYSTEM with an interruption of power
supply/SUPPLY MAINS ALARM CONDITION;
k) for CONTROLLERS for FORCED AIR DEVICES, the following warning statements:
– a caution that the HOSE, if allowed to contact the PATIENT, can lead to thermal injury, if
appropriate;
– a description of system operating modes and PATIENT conditions where the HEATING
DEVICE can be safely used;
– a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
– * a statement that the HOSE NOZZLE needs to be connected to a BLANKET. The following
statement shall accompany the "no FREE HOSING" safety sign shown in Annex D:
"CAUTION! HOSE NOZZLE SHALL be connected to a compatible forced air BLANKET or
thermal injury may occur."
201.7.9.2.9 Operating instructions
Addition:
201.7.9.2.9.101 Additional requirements for start-up PROCEDURE
The instructions for use shall include a method for testing the function of the ALARM SYSTEM for
each of the ALARM CONDITIONS specified in this document, if not performed automatically during
start up.
201.7.9.2.9.102 Additional requirements for operating instructions
The following shall appear in the instructions for use:
a) the approximate time required for the CONTACT SURFACE TEMPERATURE to heat up from
23 °C ± 2 °C to 37 °C, when operated under CONDITIONS OF ADEQUATE HEAT DISCHARGE as
specified in Annex EE;
ALARM SYSTEM.
b) a description of how and when to verify the functionality of the
201.7.9.2.9.103 Additional requirements for operating instructions for BLANKETS
The instructions for use for BLANKETS shall contain the following:
a) a description of system operating modes and PATIENT conditions where the system can be
safely used;
b) a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
c) an indication of how the BLANKET is to be positioned during NORMAL USE, for example:
i) over the PATIENT,
ii) under the PATIENT,
iii) directly in contact with the PATIENT,
iv) separated from the PATIENT by an intermediate layer, or layers, of material,
v) whether it has to be used flat (without creases),
vi) whether it can be wrapped around the PATIENT;
d) *a statement identifying which CONTROLLER(S) can be used safely with the BLANKET. The
description shall include, as applicable, the CONTROLLER model number, revision level,
product version, options or any other element that could affect the safety of the combination;
e) *a warning against using the device distal to arterial cross clamping;
NOTE BLANKETS can be used proximal to the clamped artery without any additional RISK.
f) a warning describing the possible HAZARD of using the device with ischemic limbs.
201.7.9.2.9.104 Additional requirements for operating instructions for temperature
sensors
The instructions for use for temperature sensors required for temperature control, which are
designed to be attached to, or inserted into, a PATIENT shall have their intended use identified.

– 18 – IEC 60601-2-35:2020 © IEC 2020
201.7.9.2.13 Maintenance
Addition:
201.7.9.2.13.101 Additional requirements for maintenance
The following shall appear in the documentation:
– particulars of any necessary calibration procedure(s);
– information as to how to confirm that the independent THERMAL CUT-OUT is operational.
201.8 Protection against electrical HAZARDS from ME EQUIPMENT
Clause 8 of the general standard applies, except as follows:
201.8.1 * Fundamental rule of protection against electric shock
Addition to item b):
– contact between a PATIENT and the heat-transfer fluid caused by a leak from a fluid-filled
MATTRESS;
– * perforation of a liquid-filled MATTRESS heated by circulation of liquid from a remote unit;
– perforation of the ENCLOSURE of a HEATING DEVICE separated from the SUPPLY MAINS by a
transformer (see 15.5 of the general standard).
201.8.5.1.2 MEANS OF PATIENT PROTECTION (MOPP)
Addition:
201.8.5.1.2.101 * Additional requirements for MEANS OF PATIENT PROTECTION (MOPP)
The electrical circuit within the APPLIED PART shall be isolated from earth by at least one MOPP
and from MAINS by at least two MOPP. Where a transformer is used to achieve this isolation, it
need not meet 15.5.3.
Compliance is checked by inspection of the HEATING DEVICES and examination of the circuit
diagram.
201.8.7.4.7 Measurement of the PATIENT LEAKAGE CURRENT
Addition:
PATIENT LEAKAGE
201.8.7.4.7.101 Additional requirements for measurement of the
CURRENT
APPLIED PART consisting of a surface of insulating material is tested using metal foil as
An
mentioned in 8.7.4.7 of the general standard:
a) for an APPLIED PART large enough for a PATIENT not to be in contact with the whole surface
of the APPLIED PART, foil of area 100 cm × 30 cm shall be used; or
b) for an APPLIED PART whose area is less than 100 cm × 30 cm, the whole APPLIED PART shall
be covered by foil.
For a liquid-filled MATTRESS heated
...

IEC 60601-2-35 ®
Edition 2.1 2023-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Medical electrical equipment –
Part 2-35: Particular requirements for the basic safety and essential performance
of heating devices using blankets, pads or mattresses and intended for heating
in medical use
Appareils électromédicaux –
Partie 2-35 : Exigences particulières pour la sécurité de base et les
performances essentielles des dispositifs de réchauffage utilisant des
couvertures, des coussins ou des matelas et destinés au réchauffage des
patients en usage médical
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IEC 60601-2-35 ®
Edition 2.1 2023-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Medical electrical equipment –
Part 2-35: Particular requirements for the basic safety and essential performance
of heating devices using blankets, pads or mattresses and intended for heating
in medical use
Appareils électromédicaux –
Partie 2-35 : Exigences particulières pour la sécurité de base et les
performances essentielles des dispositifs de réchauffage utilisant des
couvertures, des coussins ou des matelas et destinés au réchauffage des
patients en usage médical
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 11.040, 11.140.01 ISBN 978-2-8322-8119-2

IEC 60601-2-35 ®
Edition 2.1 2023-12
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Medical electrical equipment –
Part 2-35: Particular requirements for the basic safety and essential performance
of heating devices using blankets, pads or mattresses and intended for heating
in medical use
Appareils électromédicaux –
Partie 2-35 : Exigences particulières pour la sécurité de base et les
performances essentielles des dispositifs de réchauffage utilisant des
couvertures, des coussins ou des matelas et destinés au réchauffage des
patients en usage médical
– 2 – IEC 60601-2-35:2020+AMD1:2023 CSV
© IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
INTRODUCTION to Amendment 1 . 7
201.1 Scope, object and related standards . 8
201.2 Normative references . 10
201.3 Terms and definitions. 10
201.4 General requirements . 13
201.5 General requirements for testing ME EQUIPMENT . 14
201.6 Classification of ME EQUIPMENT and ME SYSTEMS . 14
201.7 ME EQUIPMENT identification, marking and documents . 14
201.8 Protection against electrical HAZARDS from ME EQUIPMENT . 18
201.9 Protection against MECHANICAL HAZARDS of ME EQUIPMENT and ME SYSTEMS . 24
201.10 Protection against unwanted and excessive radiation HAZARDS . 26
201.11 Protection against excessive temperatures and other HAZARDS . 26
201.12 Accuracy of controls and instruments and protection against hazardous
outputs . 28
201.13 HAZARDOUS SITUATIONS and fault conditions for ME EQUIPMENT . 33
201.14 PROGRAMMABLE ELECTRICAL MEDICAL SYSTEMS (PEMS) . 38
201.15 Construction of ME EQUIPMENT . 38
201.16 ME SYSTEMS . 42
201.17 Electromagnetic compatibility of ME EQUIPMENT and ME SYSTEMS . 42
202 ELECTROMAGNETIC DISTURBANCES – Requirements and tests . 43
208 General requirements, tests and guidance for ALARM SYSTEMS IN MEDICAL
ELECTRICAL EQUIPMENT and MEDICAL ELECTRICAL SYSTEMS. 43
210 * Requirements for the development of PHYSIOLOGIC CLOSED-LOOP CONTROLLERS . 43
Annexes . 44
Annex D (informative) Symbols on marking . 44
Annex AA (informative) Particular guidance and rationale . 45
Annex BB (normative) Determination of the LAGGING MATERIAL . 57
Annex CC (normative) * Determination of heat transfer towards the PATIENT . 58
Annex DD (normative) * Determination of heat transfer away from the PATIENT . 60
Annex EE (normative) CONDITIONS OF ADEQUATE HEAT DISCHARGE . 61
Annex FF (normative) Test procedure for maximum CONTACT SURFACE TEMPERATURE
for FORCED AIR DEVICES . 62
Annex GG (normative) Test procedure for maximum CONTACT SURFACE TEMPERATURE
for FORCED AIR DEVICES under SINGLE FAULT CONDITION. 64
Annex HH (normative) Safety test procedure for average CONTACT SURFACE
TEMPERATURE for FORCED AIR DEVICES . 65
Bibliography . 67
Index of defined terms used in this document . 69

Figure 201.101 – Positioning of temperature sensors on the contact surface of the
heated area of a HEATING DEVICE (see 201.12.4.101 and 201.12.4.105) . 11

© IEC 2023
Figure 201.102 – Example of the positioning of temperature sensors on the contact
surface of the heated areas of a HEATING DEVICE having more than one separately
heated area . 12
Figure 201.103 – Apparatus for the spark ignition test . 22
Figure 201.104 – Ramp for the impact test on PADS . 24
Figure 201.105 – Partial covering conditions . 26
Figure 201.106 – Method of folding BLANKETS . 35
Figure 201.107 – Examples of folds . 37
Figure 201.108 – Positions of a BLANKET for the RUCK-RESISTANCE RUCK resistance test . 42
Figure AA.1 – Illustration of the main requirements of this document . 45
Figure HH.1 – Sensor locations – Average CONTACT SURFACE TEMPERATURE . 66

Table 201.101 – * Additional ESSENTIAL PERFORMANCE requirements . 14
Table 201.102 – Temperature limits in dependency to time . 39

– 4 – IEC 60601-2-35:2020+AMD1:2023 CSV
© IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-35: Particular requirements for the basic safety
and essential performance of heating devices using blankets,
pads or mattresses and intended for heating in medical use

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,
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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
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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.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60601-2-35 edition 2.1 contains the second edition (2020-09) [documents
62D/1765/FDIS and 62D/1777/RVD] and its amendment 1 (2023-12) [documents
62D/2088/FDIS and 62D/2108/RVD].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red
text. A separate Final version with all changes accepted is available in this publication.

© IEC 2023
International Standard IEC 60601-2-35 has been prepared by IEC technical committee 62D:
Electromedical equipment, of IEC technical committee 62: Electrical equipment in medical
practice.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this document, the following print types are used:
– requirements and definitions: roman type;
– test specifications: italic type;
– informative material appearing outside of tables, such as notes, examples and references: in smaller type.
Normative text of tables is also in a smaller type;
– TERMS DEFINED IN CLAUSE 3 OF THE GENERAL STANDARD, IN THIS PARTICULAR STANDARD OR AS
NOTED: SMALL CAPITALS.
In referring to the structure of this document, the term
– "clause" means one of the seventeen numbered divisions within the table of contents,
inclusive of all subdivisions (e.g. Clause 7 includes subclauses 7.1, 7.2, etc.);
– "subclause" means a numbered subdivision of a clause (e.g. 7.1, 7.2 and 7.2.1 are all
subclauses of Clause 7).
References to clauses within this document are preceded by the term "Clause" followed by the
clause number. References to subclauses within this particular standard are by number only.
In this document, the conjunctive "or" is used as an "inclusive or" so a statement is true if any
combination of the conditions is true.
The verbal forms used in this document conform to usage described in Clause 7 of the ISO/IEC
Directives, Part 2. For the purposes of this document, the auxiliary verb:
– "shall" means that compliance with a requirement or a test is mandatory for compliance with
this document;
– "should" means that compliance with a requirement or a test is recommended but is not
mandatory for compliance with this document;
– "may" is used to describe a permissible way to achieve compliance with a requirement or
test.
An asterisk (*) as the first character of a title or at the beginning of a paragraph or table title
indicates that there is guidance or rationale related to that item in Annex AA.
A list of all parts of the 60601 International Standard, published under the general title Medical
electrical equipment, can be found on the IEC website.

– 6 – IEC 60601-2-35:2020+AMD1:2023 CSV
© IEC 2023
The committee has decided that the contents of this document and its amendment 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 The attention of users of this document is drawn to the fact that equipment manufacturers and testing
organizations may 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 committees that the content of this publication be adopted for
implementation nationally not earlier than 3 years from the date of publication.

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 publication using a colour printer.

© IEC 2023
INTRODUCTION
The minimum safety requirements specified in this particular standard are considered to provide
for a practical degree of safety in the operation for HEATING DEVICES using BLANKETS, PADS or
MATTRESSES and intended for heating in medical use.
While K (degree Kelvin) is the recognized unit and symbol for absolute temperature and
temperature difference, °C has been used throughout this document because all measurements
are commonly made using equipment marked with the Celsius temperature scale.

INTRODUCTION to Amendment 1
At the October 2019 meeting of IEC SC 62D in Shanghai, China, the subcommittee discussed
the need for administrative/technical changes to most 62D standards after completion of the
amendment projects within the IEC 60601-1 series. Those projects were all completed and the
amendments published in 2020.
The full list of IEC SC 62D documents that will be amended or revised can be found within the
IEC document 62D/1792/DC. The results and comments on the DC can be found within
62D/1808/INF. The review report for this amendment is 62D/1815/RR.

– 8 – IEC 60601-2-35:2020+AMD1:2023 CSV
© IEC 2023
MEDICAL ELECTRICAL EQUIPMENT –

Part 2-35: Particular requirements for the basic safety
and essential performance of heating devices using blankets,
pads or mattresses and intended for heating in medical use

201.1 Scope, object and related standards
Clause 1 of the general standard applies, except as follows:
201.1.1 * Scope
Replacement:
This part of 60601 International Standard applies to the BASIC SAFETY and ESSENTIAL
PERFORMANCE of HEATING DEVICES using BLANKETS, PADS or MATTRESSES in medical use, also
referred to as ME EQUIPMENT. HEATING DEVICES intended to prewarm a bed are included in the
scope of this document.
If a clause or subclause is specifically intended to be applicable to ME EQUIPMENT only, or to
ME SYSTEMS only, the title and content of that clause or subclause will say so. If that is not the
case, the clause or subclause applies both to ME EQUIPMENT and to ME SYSTEMS, as relevant.
If a clause or subclause is specifically intended to be applicable to a specifically defined type
of ME EQUIPMENT, as is the case with FORCED AIR DEVICES, then the title and content of that
clause or subclause will say so. If that is not the case, the clause or subclause applies both to
ME EQUIPMENT and to ME SYSTEMS, as relevant.
HAZARDS inherent in the intended physiological function of ME EQUIPMENT or ME SYSTEMS within
the scope of this document are not covered by specific requirements in this document, except
in 7.2.13 and 8.4.1 of the general standard.
NOTE See also 4.2 of the general standard.
This document does not apply to:
– HEATING DEVICES intended for physiotherapy;
– INFANT RADIANT WARMERS; for information, see IEC 60601-2-21 [1] ;
– INFANT INCUBATORS; for information, see IEC 60601-2-19 [2];
– INFANT TRANSPORT INCUBATORS, for information, see IEC 60601-2-20 [3];
– cooling devices.
_____________
The general standard is IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and IEC 60601‑1:2005/AMD2:2020,
Medical electrical equipment – Part 1: General requirements for basic safety and essential performance.
Figures in square brackets refer to the Bibliography.

© IEC 2023
201.1.2 Object
Replacement:
The object of this particular standard is to establish particular BASIC SAFETY and ESSENTIAL
PERFORMANCE requirements, which minimize HAZARDS to PATIENTS, and OPERATORS for HEATING
DEVICES using BLANKETS, PADS or MATTRESSES and intended for heating in medical use and to
specify tests for demonstrating compliance with these requirements.
201.1.3 Collateral standards
Addition:
This particular standard refers to those applicable collateral standards that are listed in Clause
2 of the general standard and Clause 201.2 of this particular standard.
IEC 60601-1-2:2014 and IEC 60601‑1‑2:2014/AMD1:2020, IEC 60601-1-8:2006, IEC 60601-1-
8:2006/AMD1:2012 and IEC 60601‑1‑8:2006/AMD2:2020, IEC 60601-1-10:2007, IEC 60601-1-
10:2007/AMD1:2013 and IEC 60601‑1‑10:2007/AMD2:2020 apply as modified in Articles 202,
208 and 210 respectively. IEC 60601-1-3 does not apply. All other published collateral
standards in the IEC 60601-1 series apply as published.
201.1.4 Particular standards
Replacement:
In the IEC 60601 series, particular standards may modify, replace or delete requirements
contained in the general standard and collateral standards as appropriate for the particular
ME EQUIPMENT under consideration, and may add other BASIC SAFETY and ESSENTIAL
PERFORMANCE requirements.
A requirement of a particular standard takes priority over the general standard.
For brevity, IEC 60601-1:2005, IEC 60601-1:2005/AMD1:2012 and
IEC 60601‑1:2005/AMD2:2020 are referred to in this particular standard as the general
standard. Collateral standards are referred to by their document number.
The numbering of clauses and subclauses of this document corresponds to that of the general
standard with the prefix "201" (e.g. 201.1 in this document addresses the content of Clause 1
of the general standard) or applicable collateral standard with the prefix "20x" where x is the
final digit(s) of the collateral standard document number (e.g. 202.4 in this document addresses
the content of Clause 4 of the IEC 60601-1-2 collateral standard, 203.4 in this document
addresses the content of Clause 4 of the IEC 60601-1-3 collateral standard, etc.). The changes
to the text of the general standard and applicable collateral standards are specified by the use
of the following words:
"Replacement" means that the clause or subclause of the general standard or applicable
collateral standard is replaced completely by the text of this particular standard.
"Addition" means that the text of this particular standard is additional to the requirements of the
general standard or applicable collateral standard.
"Amendment" means that the clause or subclause of the general standard or applicable
collateral standard is amended as indicated by the text of this particular standard.

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Subclauses, figures or tables which are additional to those of the general standard are
numbered starting from 201.101. However due to the fact that definitions in the general standard
are numbered 3.1 through 3.147, additional definitions in this document are numbered
beginning from 201.3.201. Additional annexes are lettered AA, BB, etc., and additional items
aa), bb), etc.
Subclauses, figures or tables which are additional to those of a collateral standard are
numbered starting from 20x, where "x" is the number of the collateral standard, e.g. 202 for
IEC 60601-1-2, 203 for IEC 60601-1-3, etc.
The term "this document" is used to make reference to the general standard, any applicable
collateral standards and this particular standard taken together.
Where there is no corresponding clause or subclause in this particular standard, the clause or
subclause of the general standard or applicable collateral standard, although possibly not
relevant, applies without modification; where it is intended that any part of the general standard
or applicable collateral standard, although possibly relevant, is not to be applied, a statement
to that effect is given in this particular standard.
201.2 Normative references
NOTE Informative references are listed in the Bibliography.
Clause 2 of the general standard applies, except as follows:
Addition:
IEC 60601-1:2005, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60601-1:2005/AMD1:2012
IEC 60601-1:2005/AMD2:2020
IEC 60601-1-10:2007, Medical electrical equipment – Part 1-10: General requirements for basic
safety and essential performance – Collateral Standard: Requirements for the development of
physiologic closed-loop controllers
IEC 60601-1-10:2007/AMD1:2013
IEC 60601-1-10:2007/AMD2:2020
Replacement:
IEC 60384-14:2013, Fixed capacitors for use in electronic equipment – Part 14: Sectional
specification – Fixed capacitors for electromagnetic interference suppression and connection
to the supply mains
IEC 60384-14:2013/AMD1:2016
IEC 60601-1-2:2014, Medical electrical equipment – Part 1-2: General requirements for basic
safety and essential performance – Collateral standard: Electromagnetic disturbances –
Requirements and tests
IEC 60601-1-2:2014/AMD1:2020
201.3 Terms and definitions
For the purposes of this document, the terms and definitions specified in IEC 60601-1:2005,
IEC 60601-1:2005/AMD1:2012 and IEC 60601‑1:2005/AMD2:2020 and the following apply.

© IEC 2023
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE An index of defined terms used in this document is found beginning on page 69.
Addition:
201.3.201.1
BLANKET
APPLIED PART of HEATING DEVICE, which can be folded, for use
under or over a PATIENT
201.3.201.2
BLANKET
APPLIED PART of HEATING DEVICE intended to be used with a CONTROLLER
PATIENT
to transfer thermal energy to all or part of the body of a
201.3.202
CONDITIONS OF ADEQUATE HEAT DISCHARGE
conditions achieved when a HEATING DEVICE is supported and covered as specified in Annex EE
201.3.203.1
CONTACT SURFACE TEMPERATURE
FORCED AIR DEVICES> temperature T at the reference point of the heated APPLIED
R
PART
Note 1 to entry: See Figures 201.101 and 201.102.
Note 2 to entry: The CONTACT SURFACE TEMPERATURE for FORCED AIR DEVICES is measured by the test methods
described in Annexes FF, GG and HH.

Key
T CONTACT SURFACE TEMPERATURE reference point on the contact surface
R
Some HEATING DEVICES may have unheated areas shown in the following figures as:
Figure 201.101 – Positioning of temperature sensors on the contact surface
of the heated area of a HEATING DEVICE
(see 201.12.4.101 and 201.12.4.105)

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The temperature at the centre point of any one of the heated areas closest to the centre of the HEATING DEVICE (in the
example shown above 2, 3, 6, or 7) is treated as T .
R
Figure 201.102 – Example of the positioning of temperature sensors
on the contact surface of the heated areas of a HEATING DEVICE having
more than one separately heated area
201.3.203.2
CONTACT SURFACE TEMPERATURE
< FORCED AIR DEVICES> temperature resulting from the heat transferred to a target surface by
APPLIED PART
the
201.3.204
CONTROLLER
part of a HEATING DEVICE intended to supply and control thermal energy to a BLANKET, PAD or
MATTRESS
Note 1 to entry: This includes the HOSE, if present.
201.3.205
FORCED AIR DEVICE
HEATING DEVICE that uses air as the heat transfer medium to warm a PATIENT and is comprised
of a CONTROLLER and a BLANKET
201.3.206
FREE HOSING
hazardous practice or condition of using the CONTROLLER without a BLANKET
201.3.207
HEATING DEVICE
ME EQUIPMENT intended to supply heat to the whole or part of the body of a PATIENT by means
of heated BLANKETS, PADS, or MATTRESSES
201.3.208
HIGH HEAT TRANSFER
thermal characteristic of a HEATING DEVICE as determined according to Annex CC or Annex DD
201.3.209
HOSE
component of the CONTROLLER that is the conduit for the heat transfer medium to and/or from
the BLANKET, PAD or MATTRESS
© IEC 2023
201.3.210
INFANT
PATIENT up to the age of three months and with a weight less than 10 kg
201.3.211
LAGGING MATERIAL
polyurethane or polystyrene insulation material used in the test methods of this specification to
assist in the determination of temperature
Note 1 to entry: Specifications for LAGGING MATERIAL are given in Annexes BB and FF.
201.3.212
LOW HEAT TRANSFER
thermal characteristic of a HEATING DEVICE as determined according to Annex CC or Annex DD
201.3.213
MATTRESS
APPLIED PART of a HEATING DEVICE, which provides resilient support to the whole body of a
PATIENT
201.3.214
NOZZLE
end of the HOSE that connects to the BLANKET, PAD or MATTRESS
201.3.215
OVER-BLANKET
BLANKET designed to be used over a PATIENT
201.3.216
PAD
APPLIED PART of HEATING DEVICE, which can be bent but not folded
201.3.217
RUCK
unintended fold in a normally even surface
201.3.218
RUCK-RESISTANT BLANKET
BLANKET having a construction such that RUCKING of the flexible part is unlikely
201.3.219
UNDER-BLANKET
BLANKET designed to be used under a PATIENT
201.4 General requirements
Clause 4 of the general standard applies except as follows:
201.4.3 ESSENTIAL PERFORMANCE
Addition:
201.4.3.101 Additional requirements for ESSENTIAL PERFORMANCE
Additional ESSENTIAL PERFORMANCE requirements are found in the subclauses listed in
Table 201.101.
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Table 201.101 – * Additional ESSENTIAL PERFORMANCE requirements
Requirement Subclause
ESSENTIAL PERFORMANCE requirement 1 201.12.4.104 or generation of a TECHNICAL ALARM
CONDITION in compliance with 201.12.3.102

201.4.5 Alternative RISK CONTROL measures or test methods for me equipment or me
systems
Addition:
This particular standard specifies safety requirements for HEATING DEVICES using BLANKETS,
PADS or MATTRESSES, but alternate methods of compliance with a specific clause or subclause
by demonstrating equivalent safety will not be judged non-compliant if the MANUFACTURER has
demonstrated in his RISK MANAGEMENT FILE that the RISKS presented by the HAZARDS are of an
acceptable level when weighed against the benefits of treatment using the device.
Additional subclause:
201.4.101 Combination of equipment
For equipment which combines several heat sources, the safety requirements of other relevant
particular standards shall be considered. Further, the safety requirements of this particular
standard shall be fulfilled with the combination of the other equipment, which is approved by
the MANUFACTURER as stated in the instructions for use according to Clause 16 of the general
standard (ME SYSTEMS).
201.5 General requirements for testing ME EQUIPMENT
Clause 5 of the general standard applies.
201.6 Classification of ME EQUIPMENT and ME SYSTEMS
Clause 6 of the general standard applies, except as follows:
201.6.2 Protection against electric shock
Replacement of the last paragraph with the following new paragraph:
HEATING DEVICES shall have TYPE BF APPLIED PARTS or TYPE CF APPLIED PARTS.
201.7 ME EQUIPMENT identification, marking and documents
Clause 7 of the general standard applies, except as follows:

© IEC 2023
201.7.2.1 Minimum requirements for marking on ME EQUIPMENT and on
interchangeable parts
Addition:
201.7.2.1.101 * Additional minimum requirements for marking on ME EQUIPMENT and on
interchangeable parts
201.7.2.1.101.1 HEATING DEVICES (other than for FORCED AIR DEVICES)
A HEATING DEVICE shall be marked as follows:
NORMAL USE, whether:
a) to indicate how it is intended to be positioned in
– over the PATIENT;
PATIENT;
– under the
– directly in contact with the PATIENT;
PATIENT by an intermediate layer, or layers (for example by a water-
– separated from the
bed, other type of MATTRESS, or bedclothes);
– it has to be used flat (that is without creases), or whether it can be wrapped around the
PATIENT;
b) to warn against possible HAZARDOUS SITUATIONS from penetration by sharp objects;
c) to warn against possible HAZARDOUS SITUATIONS from folding or methods of storage, other
MANUFACTURER;
than those specified by the
d) to warn against the possibility of a HAZARDOUS SITUATION if a partial covering is caused by
pillows or other items having good thermal insulation being laid over part of the HEATING
DEVICE;
e) to specify, in the case of liquid-filled MATTRESSES intended to be used above a PAD, the
minimum amount of liquid to which the MATTRESS should be filled, and a warning that if this
minimum amount is not present a PATIENT could suffer a burn;
f) to specify, in the case of a HEATING DEVICE supplied or controlled by an external unit, that
the HEATING DEVICE shall only be used with the external unit specified by the MANUFACTURER
of the HEATING DEVICE.
201.7.2.1.101.2 CONTROLLERS
A CONTROLLER for FORCED AIR DEVICES shall be marked as follows.
HOSE shall be marked within 15 cm of the NOZZLE to caution that the NOZZLE needs to
a) The
be connected to a BLANKET. The following statement and The safety sign ISO 7010-M002
(see IEC 60601-1:2005, Table D.2, safety sign 10) shall accompany the "NO FREE
HOSING" safety sign shown in Annex D of this particular standard:.
"CAUTION! HOSE NOZZLE SHALL be connected to a compatible forced air BLANKET or thermal
injury may occur."
b) A caution that allowing the HOSE to contact the PATIENT can lead to thermal injury, if
appropriate.
c) A warning against using the device distal to arterial cross clamping and that non-observance
can lead to thermal injury.
201.7.2.1.101.3 * Temperature sensors
A temperature sensor which is designed to be attached to or inserted into a PATIENT shall have
its intended use identified clearly and unambiguously on or adjacent to the sensor.

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201.7.2.1.101.4 APPLIED PARTS (for other than FORCED AIR DEVICES) with a large
unheated border
For an APPLIED PART having an unheated border wider than 30 mm around the heated area, and
where the requirements of 201.12.4.101 are not satisfied, the outer boundary of the heated area
shall be marked on both sides of the APPLIED PART.
201.7.4.2 Control devices
Addition:
201.7.4.2.101 Additional requirements for control devices
NOTE See also 201.12.
Where provided, on ME EQUIPMENT other than FORCED AIR DEVICES, a control for setting the
CONTACT SURFACE TEMPERATURE of a HEATING DEVICE shall indicate the temperature in intervals
not greater than 1 °C (see also 201.12.1.101).
For FORCED AIR DEVICES, each heated temperature control position shall be marked in
degrees °C. Such marking shall be CLEARLY LEGIBLE.
201.7.9.2.2 Warning and safety notices
Addition:
201.7.9.2.2.101 Additional requirements for warning and safety notices
The instructions for use shall additionally contain the following:
a) a strong recommendation that the surface of the HEATING DEVICE should be checked for
freedom from mechanical damage prior to each application;
b) an indication for the use of parts of HEATING DEVICES which are intended to be used together;
c) statements, details and warnings on the use of the HEATING DEVICE in combination with other
heat sources, if applicable;
d) a warning statement that the use of materials of good thermal conductivity, such as water,
gel and similar substances, with the HEATING DEVICE not switched on can decrease the
temperature of the body of a PATIENT;
e) a warning statement regarding the RISK of electrical shock, burns or electromagnetic
interference with use of high frequency (HF) surgical instruments or endocardial catheters
while a HEATING DEVICE is in use, if applicable;
f) a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
g) a statement that means for drainage of liquid from a liquid-filled HEATING DEVICE is required
(see also 201.11.6.5.101);
h) a warning that a means for retaining a PATIENT either on or under a HEATING DEVICE may
need to be used and that the means for retaining a PATIENT should not block the fluid
pathways of the HEATING DEVICE;
i) a warning that warming transdermal medications (patches) can increase drug delivery,
resulting in possible HARM to the PATIENT;
j) a statement that the HEATING DEVICE contains an ALARM SYSTEM with an interruption of power
supply/SUPPLY MAINS ALARM CONDITION;
k) for CONTROLLERS for FORCED AIR DEVICES, the following warning statements:
– a caution that the HOSE, if allowed to contact the PATIENT, can lead to thermal injury, if
appropriate;
© IEC 2023
– a description of system operating modes and PATIENT conditions where the HEATING
DEVICE can be safely used;
– a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
– * a statement that the HOSE NOZZLE needs to be connected to a BLANKET. The following
statement shall accompany the "no FREE HOSING" safety sign shown in Annex D:
"CAUTION! HOSE NOZZLE SHALL be connected to a compatible forced air BLANKET or
thermal injury may occur."
201.7.9.2.9 Operating instructions
Addition:
201.7.9.2.9.101 Additional requirements for start-up PROCEDURE
The instructions for use shall include a method for testing the function of the ALARM SYSTEM for
each of the ALARM CONDITIONS specified in this document, if not performed automatically during
start up.
201.7.9.2.9.102 Additional requirements for operating instructions
The following shall appear in the instructions for use:
a) the approximate time required for the CONTACT SURFACE TEMPERATURE to heat up from
23 °C ± 2 °C to 37 °C, when operated under CONDITIONS OF ADEQUATE HEAT DISCHARGE as
specified in Annex EE;
ALARM SYSTEM.
b) a description of how and when to verify the functionality of the
201.7.9.2.9.103 Additional requirements for operating instructions for BLANKETS
The instructions for use for BLANKETS shall contain the following:
a) a description of system operating modes and PATIENT conditions where the system can be
safely used;
b) a statement that the OPERATOR should monitor the temperature of the PATIENT at regular
intervals;
c) an indication of how the BLANKET is to be positioned during NORMAL USE, for example:
i) over the PATIENT,
ii) under the PATIENT,
iii) directly in contact with the PATIENT,
iv) separated from the PATIENT by an intermediate layer, or layers, of material,
v) whether it has to be used flat (without creases),
vi) whether it can be wrapped around the PATIENT;
d) *a statement identifying which CONTROLLER(S) can be used safely with the BLANKET. The
description shall include, as applicable, the CONTROLLER model number, revision level,
product version, options or any other element that could affect the safety of the combination;
e) *a warning against using the device distal to arterial cross clamping;
NOTE BLANKETS can be used proximal to the clamped artery without any additional RISK.
f) a warning describing the possible HAZARD of using the device with ischemic limbs.
201.7.9.2.9.104 Additional requirements for operating instructions for temperature
sensors
The instructions for use for temperature sensors required for temperature control, which are
designed to be attached to, or inserted into, a PATIENT shall have
...