EN ISO 13732-1:2008

SLOVENSKI STANDARD
01-december-2008
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SIST EN ISO 13732-1:2007
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Ergonomics of the thermal environment - Methods for the assessment of human
responses to contact with surfaces - Part 1: Hot surfaces (ISO 13732-1:2006)
Ergonomie der thermischen Umgebung - Bewertungsverfahren für menschliche
Reaktionen bei Kontakt mit Oberflächen - Teil 1: Heiße Oberflächen (ISO 13732-1:2006)
Ergonomie des ambiances thermiques - Méthodes d'évaluation de la réponse humaine
au contact avec des surfaces - Partie 1: Surfaces chaudes (ISO 13732-1:2006)
Ta slovenski standard je istoveten z: EN ISO 13732-1:2008
ICS:
13.180 Ergonomija Ergonomics
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 13732-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2008
ICS 13.180 Supersedes EN ISO 13732-1:2006
English Version
Ergonomics of the thermal environment - Methods for the
assessment of human responses to contact with surfaces - Part
1: Hot surfaces (ISO 13732-1:2006)
Ergonomie des ambiances thermiques - Méthodes
d'évaluation de la réponse humaine au contact avec des
surfaces - Partie 1: Surfaces chaudes (ISO 13732-1:2006)
This European Standard was approved by CEN on 25 August 2008.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13732-1:2008: E
worldwide for CEN national Members.

Contents Page
Foreword.3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC .4
Annex ZB (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC .5

Foreword
The text of ISO 13732-1:2006 has been prepared by Technical Committee ISO/TC 159 “Ergonomics” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 13732-1:2008 by
Technical Committee CEN/TC 122 “Ergonomics” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by March 2009, and conflicting national standards shall be withdrawn at
the latest by December 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 13732-1:2006.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EC Directive(s).
For relationship with EC Directive(s), see informative Annexes ZA and ZB, which are integral part of this
document.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 13732-1:2006 has been approved by CEN as a EN ISO 13732-1:2008 without any
modification.
Annex ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 98/37/EC on machinery, amended by 98/79/EC.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard given in Table ZA.1 confers, within the limits of the scope of this standard, a
presumption of conformity with the relevant Essential Requirements of that Directive and associated EFTA
regulations.
Table ZA.1 — Correspondence between this European Standard and Directive 98/37/EC,
amended by 98/79/EC
Clause(s)/sub-clause(s) of this EN Essential Requirements (ERs) Qualifying remarks/Notes
of Directive 98/37/EC, amended
by 98/79/EC
3, 4, 5.2 to 5.7, and Annex B
1.5.5 -
WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling within
the scope of this standard.
Annex ZB
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 2006/42/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide a means of conforming to Essential Requirements of the
New Approach Directive 2006/42/EC on machinery.
Once this standard is cited in the Official Journal of the European Communities under that Directive and has
been implemented as a national standard in at least one Member State, compliance with the normative
clauses of this standard given in Table ZB.1 confers, within the limits of the scope of this standard, a
presumption of conformity with the relevant Essential Requirements of that Directive and associated EFTA
regulations.
Table ZB.1 — Correspondence between this European Standard and Directive 2006/42/EC
Clause(s)/sub-clause(s) of this EN Essential Requirements (ERs) Qualifying remarks/Notes
of Directive 2006/42/EC
All clauses Annex I: 1.1.6, 1.5.5, 1.7.2 -

WARNING — Other requirements and other EU Directives may be applicable to the product(s) falling within
the scope of this standard.
INTERNATIONAL ISO
STANDARD 13732-1
First edition
2006-09-01
Ergonomics of the thermal
environment — Methods for the
assessment of human responses to
contact with surfaces —
Part 1:
Hot surfaces
Ergonomie des ambiances thermiques — Méthodes d'évaluation de la
réponse humaine au contact avec des surfaces —
Partie 1: Surfaces chaudes
Reference number
ISO 13732-1:2006(E)
©
ISO 2006
ISO 13732-1:2006(E)
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ii © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 2
3 Terms and definitions. 2
4 Burn thresholds . 3
4.1 General. 3
4.2 Burn threshold data. 4
5 Assessment of risk of burning . 10
5.1 Procedure . 10
5.2 Identification of hot, touchable surfaces. 10
5.3 Task analysis. 11
5.4 Measurements of surface temperatures. 11
5.5 Choice of applicable burn threshold value . 12
5.6 Comparison of surface temperature and burn threshold. 13
5.7 Determination of risk of burning . 14
5.8 Repetition . 14
6 Protective measures. 15
6.1 General. 15
6.2 No risk of burning. 15
6.3 Risk of burning. 15
7 Guidance for setting surface temperature limit values . 16
7.1 Procedure . 16
7.2 Assessment of risk of burning . 16
7.3 Decision upon protective measures. 16
7.4 Selection of appropriate values . 16
7.5 Setting of surface temperature limit value. 17
Annex A (informative) Scientific background . 18
Annex B (normative) Contact periods. 20
Annex C (informative) Flow charts for application of this part of ISO 13732. 21
Annex D (informative) Thermal properties of selected materials. 23
Annex E (informative) Examples of protective measures against burns . 24
Annex F (informative) Example for assessment of risk of burning . 26
Annex G (informative) Examples for setting surface temperature limit values. 31
Annex H (informative) Safety signs for hot surfaces. 35
Bibliography . 37

ISO 13732-1:2006(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 13732-1 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 122, Ergonomics, in collaboration with Technical Committee ISO/TC 159, Ergonomics,
Subcommittee SC 5, Ergonomics of the physical environment, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
ISO 13732 consists of the following parts, under the general title Ergonomics of the thermal environment —
Methods for the assessment of human responses to contact with surfaces:
⎯ Part 1: Hot surfaces
⎯ Part 2: Human contact with surfaces at moderate temperature [Technical Specification]
⎯ Part 3: Cold surfaces
iv © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
Introduction
When human skin comes into contact with a hot solid surface, burns may occur. Whether or not they do
depends on a number of factors, the most important of which are
⎯ the temperature of the surface,
⎯ the material of the surface,
⎯ the period of contact between the skin and the surface,
⎯ the structure of the surface, and
⎯ the sensitivity of the human being who comes into contact with the surface (e.g. child or adult).
Other factors can also play a part but are of minor importance. In Annex A the scientific background is
presented and in the Bibliography publications concerning the objective are listed.
This part of ISO 13732 contains a collection of temperature threshold values for burns when the skin is in
contact with a hot solid surface (Clause 4). It also contains a method for the assessment of the risk of burning,
i.e. the application of the provided ergonomics data within a risk assessment procedure (Clause 5). A further
application of the data may be the specification of temperature limit values for hot surfaces. Such temperature
limit values may be specified in product standards or in regulations in order to prevent human beings
sustaining a burn when in contact with the surface of a hot product. Guidance on how to select reasonable
temperature limit values for that purpose is given in Clause 7. For different products with the same risk of
burning it is reasonable to establish identical surface temperature limit values. Therefore, this part of
ISO 13732 provides the possibility of harmonizing such temperature limit values for all kind of products.
Touching a hot surface may take place intentionally, e.g. to operate an electrically or gas powered machine or
tool, or unintentionally, when a person is near a hot object. The period of contact with the hot surface will be
different if the object is touched intentionally than if it is touched unintentionally. Considering human reaction
times and their distribution in the population, 0,5 s is the minimum applicable contact period for unintentional
touching of a hot surface for healthy adults on an acceptable safety level. For intentional touching the
minimum applicable contact period will be longer. For the application of this part of ISO 13732, it is essential
to select a contact period which best represents the real circumstances when a hot product is touched.
Guidance for such selection is given in Annex B.
The ergonomics data provided in this part of ISO 13732 are mainly based on scientific research and represent,
as far as is known, the behaviour of the human skin when in contact with a hot surface. Some of the data (e.g.
burn threshold data for very short contacts of 0,5 s) are not directly based on scientific research but are
deduced by extrapolation of the known threshold curves or by reasonable conclusion using scientific results.
The temperature threshold values provided in this part of ISO 13732 are valid for burning the skin when in
contact with hot surfaces. For the time being there are not sufficient scientific data available on the effects of
discomfort and pain to for them to be included in this part of ISO 13732. Some data for pain can be derived
from national standards (see Annexes A and the Bibliography). Research projects are planned for obtaining
data for discomfort and pain. When the results of these projects are available, this part of ISO 13732 may be
revised in order to also include discomfort and pain temperature threshold values. ISO 13732-2 deals also
with discomfort.
This part of ISO 13732 does not provide burn data on the skin that comes into contact with liquids or gases.
NOTE With the exception of water there are no such data available up to now. For water and liquids with similar heat
capacity and heat flow properties burn threshold values for bare metals can be chosen.
INTERNATIONAL STANDARD ISO 13732-1:2006(E)

Ergonomics of the thermal environment — Methods for the
assessment of human responses to contact with surfaces —
Part 1:
Hot surfaces
1 Scope
This part of ISO 13732 provides temperature threshold values for burns that occur when human skin is in
contact with a hot solid surface.
It also describes methods for the assessment of the risks of burning, when humans could or might touch hot
surfaces with their unprotected skin.
This part of ISO 13732 also gives guidance for cases where it is necessary to specify temperature limit values
for hot surfaces; it does not set surface temperature limit values.
NOTE 1 Such temperature limit values can be specified in specific product standards or in regulations in order to
prevent human beings sustaining burns when in contact with the hot surface of a product.
This part of ISO 13732 deals with contact periods of 0,5 s and longer.
It is applicable to contact when the surface temperature is essentially maintained during the contact (see 4.1).
It is not applicable if a large area of the skin (approximately 10 % or more of the skin of the whole body) can
be in contact with the hot surface. Neither does it apply to skin contact of more than 10 % of the head or
contact which could result in burns of vital areas of the face.
NOTE 2 In some cases, the results of contact with a hot surface can be more serious for the individual, for example:
⎯ burns resulting in the restriction of airways;
⎯ large burns (more than 10 % of the body surface) that can impair the circulation by fluid loss;
⎯ heating of a large proportion of the head or whole body that could lead to unacceptable heat strain even in the
absence of burning.
This part of ISO 13732 is applicable to the hot surfaces of all kind of objects: equipment, products, buildings,
natural objects, etc. For the purposes of simplification, it mentions only products; nevertheless, it applies to all
other objects as well.
It is applicable to products used in any environment, e.g. in the workplace, in the home.
It is applicable to hot surfaces of products that may be touched by healthy adults, children, elderly people and
also by people with physical disabilities.
It does not provide data for the protection against discomfort or pain.
ISO 13732-1:2006(E)
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments).
ISO 7726:1998, Ergonomics of the thermal environment — Instruments for measuring physical quantities
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
touchable surface
surface of a product that can be touched by a person’s skin
3.2
surface temperature
T
s
temperature of a material’s surface
NOTE Surface temperature is expressed in degrees Celsius (°C).
3.3
contact period
D
duration of contact of the skin with the surface
NOTE Contact period is expressed in seconds (s).
3.4
thermal inertia
product of density (ρ), thermal conductivity (K) and specific thermal capacity (c) of a material
3.5
burn threshold
surface temperature defining the boundary between no burn and a superficial partial thickness burn, caused
by contact of the skin with this surface for a specified contact period
NOTE Burns are classified into three levels, depending on severity.
⎯ superficial partial thickness burn:
in all but the most superficial burns, the epidermis is completely destroyed but the hair follicles and sebaceous glands
as well as the sweat glands are spared.
⎯ deep partial thickness burn:
a substantial part of the dermis and all sebaceous glands are destroyed and only the deeper parts of the hair follicles
or the sweat glands survive.
⎯ whole thickness burn:
the full thickness of the skin is destroyed and there are no surviving epithelial elements.
2 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
4 Burn thresholds
4.1 General
This clause provides surface temperature data for burn thresholds.
NOTE The occurrence of burning depends on the temperature of the skin and on the period of raised skin
temperature. The connection between skin temperature, the period of its influence and occurrence of burning has been
scientifically studied and is known (see Annex A). But it is not practicable by simple means to measure the temperature of
the skin during its contact with the hot surface of a product. Therefore, in this part of ISO 13732 it is not the temperature
values of the skin which are specified but the temperature values of hot surfaces of products which, when in contact with
the skin, lead to burns (the burn thresholds). The temperature of a surface of a product is simply measurable by
appropriate measuring facilities.
The surface temperatures which lead to burns during contact of the skin with a hot product depend on the
material of which the product consists, and on the period of the contact of the skin with the surface. This
relationship is presented in Figure 1, which shows this relationship for several groups of materials which have
similar heat conductivity properties and therefore similar burn thresholds.

Key
D contact period
T surface temperature
s
1 plastics
2 ceramics
3 metals
4 burn threshold
Figure 1 — Illustration of general relationship between burn threshold and contact period when hot
surface is touched by skin
ISO 13732-1:2006(E)
A point on a burn threshold curve indicates, for a particular contact period, that surface temperature which lies
between non-injury of the skin and the onset of a superficial partial thickness burn when the skin comes into
contact with the hot surface. Surface temperature values lying below the curve in general do not lead to a burn.
Surface temperature values lying above the curve will lead to a burn of the skin (see also Annex A).
The illustrative Figure 1 only serves to provide a better understanding and does not accurately represent the
burn threshold data. The exact burn threshold values are to be taken from Figures 2, 5, 6 and 7 and Table 1.
For short contact periods the burn thresholds are not drawn as lines in the illustrative Figure 1 and the detailed
Figures 2, 5, 6 and 7, but as spreads. This takes into account the fact that for short contact periods the
knowledge of the temperature boundary between non-burning and the onset of burning is not complete. The
burn threshold depends on several factors, including thickness of the skin at the touching point, moisture of
the skin’s surface (sweating), contamination of the skin (e.g. grease), touching force differences between the
heat conductivity properties of materials which have been combined in one group, uncertainties of the
scientific determination of the burn threshold values (see also Annex A). However, these influences are
considered to be minor compared to the influence of the heat conductivity properties of the different material
groups.
For longer contact periods the uncertainties are less than for short contact periods. So for long contact periods
exact values for burn thresholds are specified. The differences in the values for different groups of materials
also disappear for long contact periods.
The data given presumes that the surface temperature is essentially maintained during the contact period
either by the mass of the product or by a heating source. These conditions will describe exposures which are
in conformity with the worst case.
4.2 Burn threshold data
4.2.1 Burn thresholds for contact periods between 0,5 s and 10 s
4.2.1.1 General
In the case of short contact (contact periods of 0,5 s to 10 s), the burn threshold spreads are not set in
numbers but are reflected in graphs in relation to the contact period. The burn thresholds of materials with
similar heat conductivity properties are combined to represent one spread.
4.2.1.2 Uncoated metals
The burn thresholds presented in Figure 2 are valid for the smooth surfaces of uncoated metals. In the case of
rough metal surfaces, however, the values may lie above those for smooth surfaces, but not more than 2 °C
beyond the upper limit of the indicated burn threshold spread.
4 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
Key
D contact period, s
T surface temperature, °C
s
1 no burn
2 burn threshold
3 burn
Figure 2 — Burn threshold spread when the skin in contact with hot, smooth surface made of bare
(uncoated) metal
4.2.1.3 Coated metals
The values for the effect of coating a metal are shown in Figures 3 and 4. The values reflect the rise of the
burn threshold above the burn threshold for uncoated metal. In order to obtain a burn threshold for coated
metal, the value for the rise of the burn threshold in Figure 3 or 4 and the burn threshold for the uncoated
metal in Figure 2 have to be added.
ISO 13732-1:2006(E)
Key
D contact period, s
∆T rise in surface temperature, °C
s
a
50 µm.
b
100 µm.
c
150 µm.
Figure 3 — Rise in burn threshold spread from Figure 2 for metals coated by lac
of 50 µm, 100 µm and 150 µm
Key
D contact period, s
∆T rise in surface temperature, °C
s
a
Enamel (160 µm)/powder (60 µm).
b
Powder (90 µm).
c
Polyamide 11 or 12 (400 µm thickness).
Figure 4 — Rise in burn threshold spread from Figure 2 for metals coated by powder
(60 µm and 90 µm), enamel (160 µm) and polyamide 11 or 12 (400 µm thickness)
6 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
4.2.1.4 Ceramics, glass and stone materials
The burn threshold spread for ceramics, glass ceramics, glass, porcelain and stone materials (marble,
concrete) is shown in Figure 5.
The burn thresholds for marble and concrete lie towards the lower limit of the spread. Burn thresholds for
glass lie towards the upper limit of the spread.

Key
D contact period, s
T surface temperature, °C
s
1 no burn
2 burn threshold
3 burn
Figure 5 — Burn threshold spread when skin is contact with hot, smooth surface made of ceramics,
glass and stone materials
4.2.1.5 Plastics
The burn threshold spread for plastics (polyamide, acrylglass, polytetrafluorethylene, duroplastic) is shown in
Figure 6.
NOTE Plastics have very different levels of thermal conductivity, depending on chemical composition. The burn
threshold spread for most solid plastics is indicated in Figure 6. However, for plastics with heat conductivity properties
which differ markedly from those of the materials given here, the burn thresholds indicated cannot be used. For these
materials, burn thresholds have to be calculated, estimated or measured according to Annex A.
ISO 13732-1:2006(E)
Key
D contact period, s
T surface temperature, °C
s
1 no burn
2 burn threshold
3 burn
Figure 6 — Burn threshold spread when skin in contact with hot, smooth surface made of plastics
4.2.1.6 Wood
The burn threshold spread for wood is shown in Figure 7.
For soft woods with low moisture content the values at the upper limit of the spread are applicable. For hard
woods with high moisture content the values at the lower limit of the spread are relevant.
8 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
Key
D contact period, s
T surface temperature, °C
s
1 no burn
2 burn threshold
3 burn
Figure 7 — Burn threshold spread when skin in contact with hot, smooth surface made of wood
4.2.2 Burn thresholds for contact periods between 10 s and 1 min
For contact periods between 10 s and 1 min, a linear interpolation can be made for the specific material
between the lower and the upper border lines of the burn threshold spreads indicated in Figures 2 to 7 for a
contact period of 10 s (see 4.2.1) and the value in Table 1 corresponding to the contact period of 1 min
(see 4.2.3). So the burn threshold is obtained as a spread for contact periods near above 10 s. This spread
focuses on a single value at a contact period of 1 min.
4.2.3 Burn thresholds for contact periods of 1 min and longer
Table 1 presents burn thresholds when a surface is touched for contact periods of 1 min and longer.
Table 1 — Burn thresholds for contact periods of 1 min and longer
Burn thresholds for contact periods of
Material
1 min 10 min 8 h and longer
°C
Uncoated metal 51 48 43
Coated metal 51 48 43
Ceramics, glass and stone materials 56 48 43
Plastics 60 48 43
Wood 60 48 43
ISO 13732-1:2006(E)
For contact periods lying between the time periods specified in Table 1, it is convenient to interpolate linearly
between the burn threshold values set for the next shorter and for the next longer contact period.
NOTE The value of 51 °C for a contact period of 1 min also applies to other materials with high thermal conductivity
which are not indicated in Table 1.
WARNING — The value of 43 °C for all materials for a contact period of 8 h and longer applies only if a
minor part of the body (less than 10 % of the entire skin surface of the body) or if a minor part of the
head (less than 10 % of the skin surface of the head) touches the hot surface. If the touching area is
not only local or if the hot surface is touched by vital areas of the face (e.g. the airways), severe
injuries may occur even if the surface temperature does not exceed 43 °C.
5 Assessment of risk of burning
5.1 Procedure
In order to assess the risk of burning if the unprotected human skin comes or could come into contact with hot
surfaces, the following procedure shall be carried out:
⎯ identification of hot, touchable surfaces;
⎯ task analysis;
⎯ measurement of the surface temperature;
⎯ choice of applicable burn threshold value;
⎯ comparison of the surface temperature and the burn threshold;
⎯ determination of the risk of burning;
⎯ repetition of the assessment.
In Figure C.1, the procedural steps are shown in a flow chart. In 5.2 to 5.8 the steps are specified in detail. An
example for the assessment is given in Annex F.
NOTE In specific cases it could be reasonable to deviate from the sequence shown in Figure C.1. For example, the
task analysis might be carried out before the identification of all hot touchable surfaces if the number of surfaces to be
considered can be reduced by this procedure, or the choice of an applicable burn threshold value might be carried out
before measurement of the surface temperature.
5.2 Identification of hot, touchable surfaces
The product having a hot surface or several hot surfaces shall be carefully considered. All necessary
information concerning the hot surface(s) of the product shall be gathered. This includes the attributes:
⎯ accessibility of the surfaces;
⎯ rough estimation of the surfaces temperatures (hot, moderate, cold);
⎯ materials of which the surfaces consist;
⎯ textures of the surfaces;
⎯ all operating conditions of the product including the worst case, i.e. the case with the highest surface
temperatures.
NOTE If more specific information is needed to determine the accessibility of the surface of a product, reference can
be made to other appropriate standards such as IEC 61032 and EN 71-1.
10 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
5.3 Task analysis
All necessary information concerning the use of the product shall be collected. By analysis or observation,
describe the activities and tasks involved in using the product. Particular attention shall be paid to possible
intentional and unintentional contact with hot surfaces and to the categories of persons (users of the product
and others) to which it may occur. The likely nature of the contact (probability and contact period) shall also be
identified.
From the task analysis, the following information is obtained:
⎯ surfaces that are, or which may be, touched;
⎯ intentional or unintentional touching;
⎯ duration of contact with surfaces;
⎯ persons who come or who might come into contact with surfaces;
⎯ probability of unintentional touching;
⎯ frequency of intentional touching;
⎯ actual range of power/temperature settings of the product during use.
All steps during the use of the product shall be included, i.e. normal use, maintenance, repair, etc.
5.4 Measurements of surface temperatures
5.4.1 Procedure
The surface temperature shall be measured on that part or those parts of the product where contact of the
skin with the surface can occur.
The measurement shall be carried out under the normal operating conditions of the product. The extreme end
of the range of the normal operating conditions shall be included so as to provide maximum surface
temperatures.
When measuring the surface temperature, care shall be taken that good contact is established between the
sensor and the surface. If necessary, use appropriate force and a conducting paste for this purpose according
to ISO 7726. The area of contact should lie flat on the surface and may not become canted. The measured
value should not be read until temperature equilibrium between the surface and the sensor has been reached.
To reach this equilibrium more quickly, it may be convenient to heat the contact sensor of the measuring
instrument at a different point of the hot surface before carrying out the actual measurement.
5.4.2 The measuring apparatus
The measurement of the surface temperature shall be carried out by means of an electrical thermometer with
a contact sensor made of metal and insignificant heat capacity. The accuracy of the instrument shall be at
least ± 1 °C in the range up to 50 °C and at least ± 2 °C in the range above 50 °C.
NOTE The data presented in this part of ISO 13732 have been evaluated using the above-mentioned measuring
facility and results obtained by other techniques may not be suitable for comparison with the data.
ISO 13732-1:2006(E)
5.5 Choice of applicable burn threshold value
5.5.1 Procedure
In order to select the applicable burn threshold value from Clause 4, information concerning the
⎯ contact period,
⎯ surface material, and
⎯ surface texture
shall be extracted from the results of the identification of touchable hot surfaces (5.2) and from the task
analysis (5.3). The selection procedure consists of the steps specified in 5.5.2 and 5.5.3.
5.5.2 Determination of contact period
5.5.2.1 General
From the results of the task analysis (5.3) it can be deduced
a) whether contact of the skin with a hot surface can occur unintentionally or intentionally, e.g. the touch of
control elements, and
b) the category of person who comes or who might come into contact with the hot surface
⎯ healthy adults,
⎯ children,
⎯ elderly people, or
⎯ people with physical disabilities.
5.5.2.2 Unintentional contact
The ability of human beings to react to and terminate unintentional contact with a hot surface after a pain
sensation depends on age and physical constitution. The contact period for unintentional contact thus differs
from one individual to another.
a) Healthy adults
For healthy adults, Table B.1 applies. In general, a minimum contact period of 1 s should be used. A
minimum contact period of 0,5 s may be selected when there is absolutely no restriction of movement for
the fastest possible withdrawal following a pain sensation from touching a hot surface. If extended
reaction time is to be expected (e.g. conditions that restrict ease of movement), a longer contact period
should be selected, 4 s is proposed.
b) Children
For children, Table B.1 applies. The minimum contact period chosen shall not be less than 1 s. If touching
a hot surface and an extended reaction duration due to their age is to be expected, at least 4 s shall be
selected.
Until 24 months children do not have reflexes quick enough to enable them to remove their hands from
what it is that burns them. They therefore do not always have the ability to get away from hot surfaces.
The contact period can be up to 15 s for very young children.
12 © ISO 2006 – All rights reserved

ISO 13732-1:2006(E)
c) Elderly people
For elderly people, Table B.1 applies. If the product is used mainly by elderly people, 1 s shall be selected
as the minimum contact period. If touching of a hot surface and extended reaction time due to their age is
to be expected, at least 4 s shall be selected.
d) People with physical disabilities
If people with physical disabilities could come into contact with a hot surface, special consideration shall
be given to this contingency, taking into account the nature of the disability and the use of the product. It
has to be decided whether Table B.1 is applicable, or if longer contact periods ought to be selected.
5.5.2.3 Intentional contact
If the hot surface is touched intentionally, then, ideally, the maximum duration of contact shall be measured. If
the maximum duration cannot be determined by measurement, a representative contact period shall be
selected with the aid of Table B.1. This duration shall then be taken as a basis for the actual contact period.
For intentional contact with a hot surface no contact period shorter than 4 s shall be used.
In general, Table B.1 applies for healthy adults, children, elderly people and people with physical disabilities. It
shall nevertheless be considered whether the product will be used by groups of people other than healthy
adults where the task may take longer than the time specified in Table B.1. In that case, the contact periods
shall be modified accordingly.
If products are specifically made for people with physical disabilities, then the nature of the disability shall be
considered in detail and expert medi
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