IEC 63203-406-1:2021

Wearable electronic devices and technologies - Part 406-1: Test method for measuring surface temperature of wrist-worn wearable electronic devices while in contact with human skin

IEC 63203-406-1:2021 defines the terms, definitions, symbols, configurations, and test methods to be used to specify the standard measurement conditions and methods for determining the contact-surface temperature of wrist-worn wearable electronic devices intended to be worn directly on a human wrist and that can be worn continuously during use. The conditions of the test do not consider perfusion and results are therefore considered conservatively. The temperature increase is induced by the thermal energy of wearable electronic devices during operation. This document gives the general procedure for the test method applicable to various wrist-worn wearable electronic devices for use by ordinary persons which in the context of this document is a healthy human adult.

Technologies et dispositifs électroniques prêts-à-porter - Partie 406-1: Méthode d’essai pour le mesurage de la température de surface des dispositifs électroniques prêts-à-porter placés au poignet au contact de la peau humaine

L‘IEC 63203-406-1:2021 définit les termes, les définitions, les symboles, les configurations et les méthodes d'essai à utiliser pour spécifier les conditions de mesure normalisées et les méthodes de détermination de la température à la surface de contact des dispositifs électroniques prêts-à-porter placés au poignet, destinés à être portés directement sur le poignet humain et qui peuvent être portés de manière continue pendant leur utilisation. Les conditions de l’essai ne prennent pas en considération la diffusion et les résultats sont par conséquent considérés avec prudence. L'augmentation de la température est induite par l'énergie thermique des dispositifs électroniques prêts-à-porter pendant leur fonctionnement. Le présent document donne la procédure générale pour la méthode d'essai applicable à divers dispositifs électroniques prêts-à-porter placés au poignet et destinés à être utilisés par des personnes ordinaires qui, dans le contexte de ce document, sont des adultes humains en bonne santé.

General Information

• Status: Published
• Publication Date: 15-Dec-2021
• ICS: 31.020 - Electronic components in general
• Technical Committee: TC 124 - Wearable electronic devices and technologies
• Drafting Committee: WG 4 - TC 124/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 16-Dec-2021
• Completion Date: 14-Jan-2022

Standards Content (Sample)

IEC 63203-406-1 ®
Edition 1.0 2021-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Wearable electronic devices and technologies –
Part 406-1: Test method for measuring surface temperature of wrist-worn
wearable electronic devices while in contact with human skin

Technologies et dispositifs électroniques prêts-à-porter –
Partie 406-1: Méthode d’essai pour le mesurage de la température de surface
des dispositifs électroniques prêts-à-porter placés au poignet au contact de la
peau humaine
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IEC 63203-406-1 ®
Edition 1.0 2021-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Wearable electronic devices and technologies –

Part 406-1: Test method for measuring surface temperature of wrist-worn

wearable electronic devices while in contact with human skin

Technologies et dispositifs électroniques prêts-à-porter –

Partie 406-1: Méthode d’essai pour le mesurage de la température de surface

des dispositifs électroniques prêts-à-porter placés au poignet au contact de la

peau humaine
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.020 ISBN 978-2-8322-1061-5

– 2 – IEC 63203-406-1:2021 © IEC 2021
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test conditions and test setup . 7
4.1 Environmental conditions . 7
4.2 Human skin-imitating fixture . 7
4.2.1 General . 7
4.2.2 Structure of the human skin-imitating fixture . 7
4.2.3 Monitoring skin-imitating temperature and heater control . 7
4.3 Stabilization time . 7
4.4 Test setup . 8
4.4.1 General . 8
4.4.2 Placement of device under test (DUT) . 8
4.4.3 Thermocouple placement . 9
4.4.4 Device operating conditions . 9
5 Test method . 9
6 Test report . 10
Annex A (informative) Low-temperature burn caused by wearable electronic devices. 11
A.1 General . 11
A.2 Low-temperature burn threshold . 11
Annex B (informative) Human skin-imitating fixture . 12
B.1 General structure . 12
B.2 Heater for imitating skin temperature . 12
Annex C (informative) Device operation scenario for the temperature test . 14
C.1 Normal operating condition scenario . 14
C.2 Abnormal operating condition scenario . 14
Bibliography . 15

Figure 1 – Test setup for evaluating the contact-surface temperature of a wearable
electronic device . 8
Figure B.1 – Structure of human skin-imitating fixture . 12
Figure B.2 – Minimum size of cover, heater, and the position of thermocouple to
monitor skin-imitating temperature . 13
Figure C.1 – Working period and duty cycle under device operating conditions . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
WEARABLE ELECTRONIC DEVICES AND TECHNOLOGIES –

Part 406-1: Test method for measuring surface temperature of wrist-worn
wearable electronic devices while in contact with human skin

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
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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.
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 63203-406-1 has been prepared by technical committee 124: Wearable electronic devices
and technologies. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
124/161/FDIS 124/168/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

– 4 – IEC 63203-406-1:2021 © IEC 2021
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/standardsdev/publications.
A list of all parts in the IEC 63203 series, published under the general title Wearable electronic
devices and technologies, can be found on the IEC website.
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,
• replaced by a revised edition, or
• amended.
WEARABLE ELECTRONIC DEVICES AND TECHNOLOGIES –

Part 406-1: Test method for measuring surface temperature of wrist-worn
wearable electronic devices while in contact with human skin

1 Scope
This part of IEC 63203 defines the terms, definitions, symbols, configurations, and test methods
to be used to specify the standard measurement conditions and methods for determining the
contact-surface temperature of wrist-worn wearable electronic devices intended to be worn
directly on a human wrist and that can be worn continuously during use. The conditions of the
test do not consider perfusion and results are therefore considered conservatively. The
temperature increase is induced by the thermal energy of wearable electronic devices during
operation. This document gives the general procedure for the test method applicable to various
wrist-worn wearable electronic devices for use by ordinary persons which in the context of this
document is a healthy human adult.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62368-1:2018, Audio/video, information and communication technology equipment – Part 1:
Safety requirements
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply:
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• ISO Online browsing platform: Available at http://www.iso.org/obp
• IEC Electropedia: Available at http://www.electropedia.org/
3.1
ambient temperature
average temperature of air or another medium in the vicinity of a wearable electronic device
Note 1 to entry: During the measurement of the ambient temperature the measuring instrument/probe should be
shielded from draughts and radiant heating.
[SOURCE: IEC 60050-816:2004, 826-10-03, modified – In the definition, "the equipment" has
been replaced with "a wearable electronic device".]

– 6 – IEC 63203-406-1:2021 © IEC 2021
3.2
human skin-imitating fixture
test fixture with thermal conductivity similar to that of human skin including internal heater to
imitate the temperature of human skin and its thermal conduction properties, as well as
providing a surface on which the device is placed during the measurement
Note 1 to entry: The human skin-imitating fixture consists of a support equipped with a heater and cover material.
3.3
skin-imitating temperature
temperature on the surface of a human skin-imitating fixture that is controlled by heater to
emulate the skin temperature of the human body
3.4
skin-contact surface
surface of the wearable electronic device that is physically in contact with the skin of the human
body
3.5
contact-surface temperature
temperature of the skin-contact surface of the wearable electronic device
Note 1 to entry: Only that part of the device which may have an elevated temperature and is in contact with the skin
shall be considered. It may not be necessary to measure the temperature of passive fixing devices, for example non-
metallic wrist bands, outside the thermal footprint of the electronic device.
3.6
normal operating condition
mode of operation that represents as closely as possible the range of normal use that can
reasonably be expected
[SOURCE: IEC 62368-1:2018, 3.3.7.4, modified – Notes to entry have been omitted.]
3.7
abnormal operating condition
temporary operating condition that is not a normal operating condition and is not a single fault
condition of the equipment itself
[SOURCE: IEC 62368-1:2018, 3.3.7.1, modified – Notes to entry have been omitted.]
3.8
single fault condition
condition of equipment with a fault under normal operating condition of a single safeguard (but
not a reinforced safeguard) or of a single component or a device
[SOURCE: IEC 62368-1:2018, 3.3.7.9, modified – Note to entry has been omitted.]
3.9
burn threshold
surface temperature defining the boundary between no burn and a superficial partial thickness
burn caused by contact of the skin with a hot surface for a specified contact period
[SOURCE: IEC GUIDE 117:2010, 3.3]

4 Test conditions and test setup
4.1 Environmental conditions
The measurements shall be carried out under the following normal environmental conditions.
• Ambient temperature: 25 °C ± 5 °C,
• Relative humidity: 25 % RH to 85 % RH,
• Atmospheric pressure: 86 kPa to 106 kPa.
4.2 Human skin-imitating fixture
4.2.1 General
A human skin-imitating fixture shall be used when measuring the contact surface temperature
of a wearable electronic device. This fixture shall imitate the thermal conduction property of the
human skin and the temperature of the surface of the human skin.
4.2.2 Structure of the human skin-imitating fixture
The human skin-imitating fixture shall be equipped with a heater, and the skin temperature shall
be imitated by the operation of the heater. The heater shall be covered with a material which
imitates the thickness and thermal conductivity of human skin. The wearable electronic device
shall be attached to the cover by the method specified by the manufacturer. All of the skin-
contact surfaces shall be in contact with the heated area of the fixture. Other detailed
descriptions about the structure can be defined as described in Annex B.
4.2.3 Monitoring skin-imitating temperature and heater control
A surface-mount-type thermocouple (TC 1) with adhesive tape made from a
low-thermal-conductivity material (λ < 0,5 W/m K) shall be attached to the surface of the cover
of the fixture, a small distance away from the device under test (DUT). The thermocouple wire
shall be no more than 0,26 mm in diameter and the measurement accuracy shall be within
±1,0 °C. The position of the thermocouple is shown in Figure 1 and Figure B.2. By monitoring
the temperature with TC 1, the heater shall be controlled to maintain a skin-imitating
temperature of 32,5 °C ± 0,5 °C in normal environmental conditions. This is to ensure that the
test is conducted under the appropriate operating conditions. A proportional-integral-derivative
(PID) controller can be used to control the heater.
NOTE The temperature of human skin can vary with the ambient temperature, the part of the human body and the
condition of the skin. The temperature of human skin is normally in the range of 30 °C to 35 °C.
Considerations should be given to the thermal mass and the heat flux of the device under test
with respect to the applicability of the human skin-imitating fixture. It should be noted that the
human skin-imitating fixture is considered as a conservative method in assessing thermal burn
injuries as it does not consider perfusion/sweating or blood circulation of the body.
4.3 Stabilization time
The measurements shall be carried out after a sufficient stabilization time has elapsed. The
first state stabilization time (step in Clause 5, list item c)) is defined as the time taken for the
test chamber temperature to stabilize at the required ambient temperature ±1,0 °C. The second
state stabilization time (step in Clause 5, list item e)) is defined as the time taken for the fixture
surface to stabilize at the required contact-surface temperature ±1,0 °C.

– 8 – IEC 63203-406-1:2021 © IEC 2021
4.4 Test setup
4.4.1 General
Figure 1 shows the test setup for measuring the electrical characteristics of a device being
tested. To measure the contact surface temperature of a wearable electronic device and the
ambient temperature, the device shall be mounted on a human skin-imitating fixture and
thermocouples for temperature measurements shall be set at appropriate positions.

Key
1 controller/driver
2 temperature controlled environment chamber
3 temperature/humidity controller
4 computer for recording
5 thermometer
6 heater controller
7 support table
8 human skin-imitating fixture
9 device under test
10 thermocouple 1 (TC 1)
11 thermocouple 2 (TC 2)
12 thermocouple 3 (TC 3)
Figure 1 – Test setup for evaluating the contact-surface
temperature of a wearable electronic device
4.4.2 Placement of device under test (DUT)
The device being tested shall be positioned on the human skin-imitating fixture in the geometric
centre of the chamber by adjusting the position of the human skin-imitating fixture. The human
skin-imitating fixture may be placed on a support table to adjust the position of the device under
test. Any support table shall be made from a low thermal conductivity material (λ < 0,5 W/mK).
The positioning of the device on the human skin-imitating fixture shall follow, where provided,
the method specified by the manufacturer to attach the device on the human body. The device
shall be attached to ensure firm contact with no significant separation from the human
skin-imitating fixture. There shall be no structures above the device being tested which may
disturb the convection air flow. There shall be no significant external air movement sources
affecting the device being tested, such as fan-forced air movement or ambient air movement.

4.4.3 Thermocouple placement
Thermocouple TC 2 for measuring the contact-surface temperature shall be positioned at the
hottest point of the skin-contact surface. The hottest point is defined as the region with the
highest temperature on the skin-contact surface of the wearable electronic device. This point
has the shortest thermal path from the heat source inside the wearable electronic device to the
contact-surface and can be determined by obtaining a thermographic mapping image of the
skin-contact surface using infrared imaging by operating the wearable electronic device before
placement on the human skin-imitating fixture. Thermocouple TC 3 for measuring the ambient
temperature shall be positioned inside the test chamber such that disturbance of the convection
air flow is avoided.
4.4.4 Device operating conditions
The normal operating conditions, abnormal operating conditions, and single fault conditions
shall be set according to methods defined in IEC 62368-1:2018, Annex B when measuring the
contact-surface temperature during device operation. The device operating mode may be set
according to its functions. Further guidance is given in Annex C. An external power source to
operate the DUT may be used instead of an internal power source such as a battery inside the
device if the heat from the internal power source is negligible.
NOTE IEC 62368-1 defines only the test temperature and thermal criteria for skin burn without providing detailed
test conditions. In this document, test conditions considering human skin and detailed measurement setup for the
precise temperature measurement are defined to prevent low-temperature skin burn during long periods of contact
with wearable electronic devices. See Annex A.
5 Test method
The procedure for testing a wearable electronic device is performed as follows.
a) The human skin-imitating fixture is placed inside the test chamber.
b) Thermocouples are placed:
– inside the test chamber for ambient temperature measurement (TC 3);
– on the surface of the human skin-imitating fixture as indicated in Figure B.2 and
connected to the heater controller for skin-imitating temperature control (TC 1); and
– on the DUT for contact-surface temperature measurement (TC 2).
c) The test chamber ambient temperature and humidity shall reach stabilization before
continuing (first state stabilization time). The chamber temperature should be set at 25,0 °C
+0 °C, −5 °C according to IEC GUIDE 117:2010, 3.7.
d) The heater of the human skin-imitating fixture is set such that the skin-imitating temperature
is maintained within the designated temperature range.
e) The human skin-imitating fixture shall reach stabilization before continuing (second state
stabilization time).
f) The DUT with the attached thermocouple is placed on the human skin-imitating fixture.
g) The operating conditions of the DUT are set. The device may be using an internal or external
power source.
h) The contact-surface temperature measurements start by operating the DUT.
i) The measurements end when the contact-surface temperature reaches its maximum stable
value within 1,0 °C in 20 min.
j) Repeat steps from list items g) to i) according to each operating condition.

– 10 – IEC 63203-406-1:2021 © IEC 2021
6 Test report
Alongside the measured maximum contact surface temperature, the report shall include the
following information:
a) identification (number and date) of this document;
b) identification and details of the test lab;
c) identification and details of the sample and manufacturer;
d) environmental conditions during the test execution;
e) test scenario;
f) device position conditions;
g) any deviations from the conditions or procedures described in this document;
h) date of test;
i) other remarks and observations.

Annex A
(informative)
Low-temperature burn caused by wearable electronic devices
A.1 General
When a wearable electronic device is being worn directly on the human body for a prolonged
period, proteins in the human skin can get damaged, even when the skin remains in contact
with a wearable electronic device at a raised temperature that is lower than the value at which
a human being would experience pain. Low-temperature burn caused by a wearable electronic
device can occur during continuous operation and during direct long-term contact with the
human skin. To determine whether a wearable electronic device meets the conditions under
which low-temperature burn is prevented, the contact surface temperature of a wearable
electronic device during operation can be measured.
This document specifies conditions under which contact-surface temperature is measured to
ensure that the contact-surface temperature of the device is below a temperature which can
cause burns to human skin, taking into consideration the device use conditions and the effect
of human skin temperature.
This document does not specify temperature limits. Temperature limits are specified in other
documents, such as IEC 62368-1. Temperature limits from IEC 62368-1 are based on an
ambient temperature of 25 °C.
A.2 Low-temperature burn threshold
For devices with substantial thermal mass and an infinite heat flux, the low-temperature burn
threshold is specified as being at 43 °C according to IEC Guide 117 if the contact time exceeds
8 h. The skin-contact temperature of a wearable electronic device should be maintained below
the limits specified in end product standards, for example, TS1 (43 °C to 48 ºC) in
IEC 62368-1:2018, 9.3 to prevent low-temperature skin burn in normal operation conditions. If
a wearable electronic device is worn for less than 8 h, the burn threshold temperature may be
determined by the criteria of ASTM C1055, Figure 1, or further guidance is available in
IEC 62368-1.
– 12 – IEC 63203-406-1:2021 © IEC 2021
Annex B
(informative)
Human skin-imitating fixture
B.1 General structure
The human skin-imitating fixture consists of a support with a heater, a heat spreader and a
cover. Figure B.1 shows the general structure of the human skin-imitating fixture. The support
consists of, for instance, flame-retardant and heat-resistant polymers with a film-type heater on
a surface controlled by an external controller. The support should be a low thermal conductivity
material (λ < 0,5 W/mK). The support and entire fixture generally will have a rounded shape,
simulating the shape of a human wrist as shown in Figure B.1. A model or replica of the human
wrist on which the wearable electronic device is intended to be worn may also be used as a
support if its thermal conductivity is less than 0,5 W/mK.
NOTE The thermal conductivity of the human body is mainly less than 0,5 W/mK except for bones, for which it is
0,63 W/mK.
Key
1 support
2 heater
3 heat spreader
4 cover
5 device under test
NOTE Figure B.1 intends to show the general structure of the fixture.
Figure B.1 – Structure of human skin-imitating fixture

B.2 Heater for imitating skin temperature
A film-type heater consists of, for instance, a resistive heating element such as metal foil inside
polyimide film. The cover material should be a material with low thermal conductivity
(λ < 0,5 W/mK), and having elasticity sufficient to have a firm surface contact against the DUT
with thermocouple (TC 2) placed between them, consisting of, for instance, silicone rubber
(polysiloxane). The thickness of the cover imitating the human skin should be 2,0 mm ± 0,1 mm.
A heat spreader with good thermal conductivity, such as a copper plate or graphite sheet, should
be placed between the film type heater and the cover, to achieve an even temperature
distribution over the complete contact area.

NOTE The human skin is composed of the epidermis, dermis, and hypodermis. The thickness of the skin varies with
the parts of the body and normally ranges from 0,5 mm around the eyelids to 2,0 mm on the back except for the
palms and soles where the thickness is over 4,0 mm.
The dimensions of the heating area and the cover should be at least 12 times larger than the
size of the skin-contact surface as defined in Figure B.2. The skin-contact surface does not
include the accessory to secure the wearable electronic device on the human body. The cover,
heater and heat spreader may be rounded to conform to the shape of the support. Thermocouple
TC 1 should be positioned to avoid thermal interference from the DUT. It should be placed at a
distance of Lx, the size of the skin-contact surface, measured from the edges of the skin-contact
surface in x direction.
Key
1 length of the skin contact surface in X-direction (Lx)
2 length of the skin contact surface in Y-direction (Ly)
3 thermocouple (TC 1)
4 heater, heat spreader, cover
5 support
6 skin-contact surface of wearable electronic device
7 minimum Lx
8 minimum Ly
Figure B.2 – Minimum size of cover, heater, and the position
of thermocouple to monitor skin-imitating temperature

– 14 – IEC 63203-406-1:2021 © IEC 2021
Annex C
(informative)
Device operation scenario for the temperature test
C.1 Normal operating condition scenario
The normal operating condition scenario is the condition of the test system simulating use on
the body by a person. A battery or an external power supply may power the device to simulate
the normal operating condition scenario. The power and duty cycle may be set according to the
normal operating condition scenario as shown in Figure C.1.

Key
1 power (W)
2 working period (s)
3 duty cycle (s)
Figure C.1 – Working period and duty cycle under device operating conditions
C.2 Abnormal operating condition scenario
An abnormal operating condition may arise as a result of improper use of the wearable
electronic device. Abnormal operating conditions may be tested by adjusting power level,
working period and duty cycle to simulate the worse conditions considered by the manufacturer.

Bibliography
IEC Guide 117:2010, Electrotechnical equipment – Temperatures of touchable hot surfaces
ASTM C1055, Standard Guide for Heated System Surface Conditions That Produce Contact
Burn Injuries
th
HAN, AQ., Thermal management and safety regulation of smart watches, Proceedings of 15
IEEE ITHERM Conference, 2016, p. 939-944
LEE, Y., HWANG, K., Skin thickness of Korean adults, Surgical and Radiologic Anatomy, 24(3),
2002, p. 183-189 (2002)
HOLMES KR., Thermal properties [viewed 2018-10-19], Available at
http://users.ece.utexas.edu /~valvano/research/Thermal.pdf.

___________
– 16 – IEC 63203-406-1:2021 © IEC 2021
SOMMAIRE
AVANT-PROPOS . 17
1 Domaine d’application . 19
2 Références normatives . 19
3 Termes et définitions . 19
4 Conditions d'essai et configuration d’essai . 21
4.1 Conditions d’environnement . 21
4.2 Dispositif imitant la peau humaine . 21
4.2.1 Généralités . 21
4.2.2 Structure du dispositif imitant la peau humaine . 21
4.2.3 Surveillance de la température imitant la peau et contrôle de l’appareil
de chauffage . 21
4.3 Temps de stabilisation . 21
4.4 Configuration d'essai . 22
4.4.1 Généralités . 22
4.4.2 Placement du dispositif en essai (DUT) . 22
4.4.3 Placement des thermocouples . 23
4.4.4 Conditions de fonctionnement du dispositif . 23
5 Méthode d’essai . 23
6 Rapport d’essai . 24
Annexe A (informative) Brûlures à basse température dues à des dispositifs
électroniques prêts-à-porter . 25
A.1 Généralités . 25
A.2 Seuil de brûlure à basse température . 25
Annexe B (informative) Dispositif imitant la peau humaine . 26
B.1 Structure générale . 26
B.2 Appareil de chauffage pour la température imitant la peau . 26
Annexe C (informative) Scénario de fonctionnement du dispositif pour l’essai de
température . 28
C.1 Scénario en condition normale de fonctionnement . 28
C.2 Scénario en conditions anormales de fonctionnement . 28
Bibliographie . 29

Figure 1 – Configuration d’essai pour évaluer la température à la surface de contact
d'un dispositif électronique prêt-à-porter . 22
Figure B.1 – Structure du dispositif imitant la peau humaine . 26
Figure B.2 – Taille minimale du couvercle, appareil de chauffage et position
du thermocouple pour surveiller la température imitant la peau . 27
Figure C.1 – Durée de fonctionnement et cycle de service en conditions de
fonctionnement du dispositif . 28

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
TECHNOLOGIES ET DISPOSITIFS ÉLECTRONIQUES PRÊTS-À-PORTER –

Partie 406-1: Méthode d’essai pour le mesurage de la température de
surface des dispositifs électroniques prêts-à-porter placés au poignet au
contact de la peau humaine
AVANT-PROPOS
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brevets.
L'IEC 63203-406-1 a été établie par le comité d'études 124 de l'IEC: Technologies et
...