SIST-TS IEC/TS 60479-1:2006

Effects of current on human beings and livestock - Part 1: General aspects

For a given current path through the human body, the danger to persons depends mainly on the magnitude and duration of the current flow. However, the time/current zones specified in this publication are, in many cases, not directly applicable in practice for designing measures of protection against electrical shock. The necessary criterion is the admissible limit of touch voltage (i.e. the product  of the current through the body called touch current and the body impedance) as a function of time. The relationship between current and voltage is not linear because the impedance of the human body varies with the touch voltage, and data on this relationship is therefore required. The different parts of the humanbody (such as the skin, blood, muscles, other tissues and joints) present to the electric current a certain impedance composed of resistive and capacitive components.[
]The values of body impedance depend on a number of factors and, in particular, on current path, on touch voltage, duration of current flow, frequency, degree of moisture of the skin, surface area of contact, pressure exerted and temperature.[
]The impedance values indicated in this technical specification result from a close examination of the experimental results available from measurements carried out principally on corpses and on some living persons.[
]This technical specification has the status of a basic safety publication in accordance with IEC Guide 104.[
]The contents of the corrigendum of October 2006 have been included in this copy.

Effets du courant sur l'homme et les animaux domestiques - Partie 1: Aspects généraux

Pour un même trajet du courant à travers le corps humain, le danger qu'encourent les personnes dépend essentiellement de l'intensité et de la durée de passage du courant. Toutefois, les zones temps/courant spécifiées dans les paragraphes suivants ne sont pas, dans beaucoup de cas, directement applicables en pratique pour concevoir la protection contre les chocs électriques; le critère est la limite admissible de la tension de contact (c'est-à-dire le produit du courant passant dans le corps humain et de son impédance) en fonction du temps. La relation entre le courant et la tension n'est pas linéaire du fait que l'impédance du corps humain varie avec la tension de contact. Il importe donc de disposer de données quant à cette relation. Les différentes parties du corps humain - telles que la peau, le sang, les muscles, d'autres tissus et les articulations - présentent pour le courant électrique une certaine impédance composée d'éléments résistifs et capacitifs.[
]Les valeurs de ces impédances dépendent de plusieurs facteurs et notamment du trajet du courant, de la tension de contact, de la durée du passage du courant, de la fréquence du courant, de l'état de l'humidité de la peau, de la surface de contact, de la pression exercée et de la température.[
]Les valeurs d'impédances indiquées dans cette spécification technique résultent d'un examen minutieux des résultats expérimentaux disponibles de mesures effectuées principalement sur des cadavres et sur quelques personnes vivantes.[
]Cette spécification technique a le statut d'une publication fondamentale de sécurité conformément au Guide 104 de la CEI.[
]Le contenu du corrigendum d'octobre 2006 a été pris en considération dans cet exemplaire.

Vplivi električnega toka na človeka in živali – 1. del: Splošno

General Information

• Status: Withdrawn
• Publication Date: 31-Aug-2006
• Withdrawal Date: 27-Apr-2020
• ICS: 13.200 - Accident and disaster control
• Technical Committee: ELI - Electrical and communication installations
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 28-Apr-2020
• Due Date: 21-May-2020
• Completion Date: 28-Apr-2020
• Ref Project: IEC/TS 60479-1 - Effects of current on human beings and livestock - Part 1: General aspects

Standards Content (Sample)

SLOVENSKI STANDARD
SIST-TS IEC/TS 60479-1:2006
01-september-2006
9SOLYLHOHNWULþQHJDWRNDQDþORYHNDLQåLYDOL±GHO6SORãQR
Effects of current on human beings and livestock - Part 1: General aspects
Effets du courant sur l'homme et les animaux domestiques - Partie 1: Aspects généraux
Ta slovenski standard je istoveten z: IEC/TS 60479-1
ICS:
13.200 3UHSUHþHYDQMHQHVUHþLQ Accident and disaster control
NDWDVWURI
SIST-TS IEC/TS 60479-1:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TS IEC/TS 60479-1:2006

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SIST-TS IEC/TS 60479-1:2006
IEC/TS 60479-1
Edition 4.0 2005-07
TECHNICAL
SPECIFICATION
SPÉCIFICATION
TECHNIQUE
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Effects of current on human beings and livestock –
Part 1: General aspects

Effets du courant sur l'homme et les animaux domestiques –
Partie 1: Aspects généraux

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XA
CODE PRIX
ICS 13.200; 29.020 ISBN 2-8318-8096-3

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SIST-TS IEC/TS 60479-1:2006
– 2 – TS 60479-1 © IEC:2005
CONTENTS
FOREWORD.6
INTRODUCTION.9

1 Scope.11
2 Normative references .12
3 Terms and definitions .12
3.1 General definitions .12
3.2 Effects of sinusoidal alternating current in the range 15 Hz to 100 Hz .13
3.3 Effects of direct current .14
4 Electrical impedance of the human body.14
4.1 Internal impedance of the human body (Z ) .14
i
4.2 Impedance of the skin (Z ).15
s
4.3 Total impedance of the human body (Z ) .15
T
4.4 Factors affecting initial resistance of the human body (R ) .15
O
4.5 Values of the total impedance of the human body (Z ).15
T
4.6 Value of the initial resistance of the human body (R ) .23
O
5 Effects of sinusoidal alternating current in the range of 15 Hz to 100 Hz.23
5.1 Threshold of perception.23
5.2 Threshold of reaction.23
5.3 Immobilization .23
5.4 Threshold of let-go .23
5.5 Threshold of ventricular fibrillation.24
5.6 Other effects related to electric shocks.24
5.7 Effects of current on the skin.25
5.8 Description of time/current zones (see Figure 20).26
5.9 Application of heart-current factor (F) .26
6 Effects of direct current .27
6.1 Threshold of perception and threshold of reaction .27
6.2 Threshold of immobilization and threshold of let-go .27
6.3 Threshold of ventricular fibrillation.27
6.4 Other effects of current .28
6.5 Description of time/current zones (see Figure 22).29
6.6 Heart factor .29

Annexes .48
Annex A (normative) Measurements of the total body impedances Z made on living
T
human beings and on corpses and the statistical analysis of the results .49
Annex B (normative) Influence of frequency on the total body impedance (Z ) .52
T
Annex C (normative) Total body resistance (R ) for direct current .53
T
Annex D (informative) Examples of calculations of Z .54
T

Bibliography.58

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TS 60479-1 © IEC:2005 – 3 –
Figure 1 – Impedances of the human body.29
Figure 2 – Internal partial impedances Z of the human body .30
ip
Figure 3 – Simplified schematic diagram for the internal impedances of the human body.31
Figure 4 – Total body impedances Z (50 %) for a current path hand to hand, for large
T
surface areas of contact in dry, water-wet and saltwater-wet conditions for a percentile
rank of 50 % of the population for touch voltages U = 25 V to 700 V, a.c. 50/60 Hz.32
T
Figure 5 – Dependence of the total impedance Z of one living person on the surface
T
33
area of contact in dry condition and at touch voltage (50 Hz) .
Figure 6 – Dependence of the total body impedance Z on the touch voltage U for a
T T
current path from the tips of the right to the left forefinger compared with large surface
areas of contact from the right to the left hand in dry conditions measured on one living
person, touch voltage range U = 25 V to 200 V, a.c. 50 Hz, duration of current flow
T
max. 25 ms .34
th
Figure 7 – Dependence of the total body impedance Z for the 50 percentile rank of
T
a population of living human beings for large, medium and small surface areas of
2 2 2
contact (order of magnitude 10 000 mm , 1 000 mm and 100 mm respectively) in dry
conditions at touch voltages U = 25 V to 200 V a.c. 50/60 Hz.35
T
th
Figure 8 – Dependence of the total body impedance Z for the 50 percentile rank of
T
a population of living human beings for large, medium and small surface areas of
2 2 2
contact (order of magnitude 10 000 mm 1 000 mm and 100 mm respectively) in
water-wet conditions at touch voltages U = 25 V to 200 V, a.c. 50/60 Hz.36
T
th
Figure 9 – Dependence of the total body impedance Z for the 50 percentile rank of
T
a population of living human beings for large, medium and small surface areas of
2 2 2
contact (order of magnitude 10 000 mm , 1 000 mm and 100 mm respectively) in
saltwater-wet conditions at touch voltages U = 25 V to 200 V, a.c. 50/60 Hz .37
T
Figure 10 – Values for the total body impedance Z measured on 10 living human
T
beings with a current path hand to hand and large surface areas of contact in dry
conditions at a touch voltage of 10 V and frequencies from 25 Hz to 20 kHz .38
Figure 11 – Values for the total body impedance Z measured on one living human
T
being with a current path hand to hand and large surface areas of contact in dry
conditions at a touch voltage of 25 V and frequencies from 25 Hz to 2 kHz.38
Figure 12 – Frequency dependence of the total body impedance Z of a population for
T
a percentile rank of 50 % for touch voltages from 10 V to 1 000 V and a frequency
range from 50 Hz to 2 kHz for a current path hand to hand or hand to foot, large
surface areas of contact in dry conditions .39
Figure 13 – Statistical value of total body impedances Z and body resistances R for a
T T
percentile rank of 50 % of a population of living human beings for the current path
hand to hand, large surface areas of contact, dry conditions, for touch voltages up to
700 V, for a.c. 50/60 Hz and d.c.40
Figure 14 – Dependence of the alteration of human skin condition on current density i
T
and duration of current flow (for detailed description of zones, see 5.7) .41
Figure 15 – Electrodes used for the measurement of the dependence of the
impedance of the human body Z on the surface area of contact .42
T

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SIST-TS IEC/TS 60479-1:2006
– 4 – TS 60479-1 © IEC:2005
Figure 16 – Oscillograms of touch voltages U and touch currents I for a.c., current
T T
path hand to hand, large surface areas of contact in dry conditions taken from
measurements .43
Figure 17 – Occurrence of the vulnerable period of ventricles during the cardiac cycle .44
Figure 18 – Triggering of ventricular fibrillation in the vulnerable period – Effects on
electro-cardiogram (ECG) and blood pressure .44
Figure 19 – Fibrillation data for dogs, pigs and sheep from experiments and for
persons calculated from statistics of electrical accidents with transversal direction of
current flow hand to hand and touch voltages U = 220 V and 380 V a.c. with body
T
impedances Z (5 %) .45
T
Figure 20 – Conventional time/current zones of effects of a.c. currents (15 Hz to
100 Hz) on persons for a current path corresponding to left hand to feet (for
explanation see Table 11).46
Figure 21 – Oscillogram of touch voltages U and touch current I for d.c., current path
T T
hand to hand, large surface areas of contact in dry conditions .46
Figure 22 – Conventional time/current zones of effects of d.c. currents on persons for
a longitudinal upward current path (for explanation see Table 13).47
Figure 23 – Let-go currents for 60 Hz sinusoidal current .47

Table 1 – Total body impedances Z for a current path hand to hand a.c. 50/60 Hz, for
T
large surface areas of contact in dry conditions .16
Table 2 – Total body impedances Z for a current path hand to hand a.c. 50/60 Hz, for
T
large surface areas of contact in water-wet conditions .17
Table 3 – Total body impedances Z for a current path hand to hand a.c. 50/60 Hz, for
T
large surface areas of contact in saltwater-wet conditions.18
Table 4 –Total body impedances Z for a current path hand to hand for medium
T
surface areas of contact in dry conditions at touch voltages U = 25 V to 200 V a.c.
T
50/60 Hz (values rounded to 25 Ω) .19
Table 5 – Total body impedances Z for a current path hand to hand for medium
T
surface areas of contact in water-wet conditions at touch voltages U = 25 V to 200 V
T
a.c. 50/60 Hz (values rounded to 25 Ω).20
Table 6 – Total body impedances Z for a current path hand to hand for medium
T
surface areas of contact in saltwater-wet conditions at touch voltages U = 25 V to
T
200 V a.c. 50/60 Hz (values rounded to 5 Ω).20
Table 7 – Total body impedances Z for a current path hand to hand for small surface
T
areas of contact in dry conditions at touch voltages U = 25 V to 200 V a.c. 50/60 Hz
T
(values rounded to 25 Ω) .20
Table 8 – Total body impedances Z for a current path hand to hand for small surface
T
areas of contact in water-wet conditions at touch voltages U = 25 V to 200 V a.c.
T
50/60 Hz (values rounded to 25 Ω) .21

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SIST-TS IEC/TS 60479-1:2006
TS 60479-1 © IEC:2005 – 5 –
Table 9 – Total body impedances Z for a current path hand to hand for small surface
T
areas of contact in saltwater-wet conditions at touch voltages U = 25 V to 200 V a.c.
T
50/60 Hz (values rounded to 5 Ω) .21
Table 10 – Total body resistances R for a current path hand to hand, d.c., for large
T
surface areas of contact in dry conditions .22
Table 11 – Time/current zones for a.c. 15 Hz to 100 Hz for hand to feet pathway :
Summary of zones of Figure 20 .26
Table 12 – Heart-current factor F for different current paths.27
Table 13 – Time/current zones for d.c. for hand to feet pathway – Summary of zones of
Figure 22 .29
Table A.1 – Total body impedances Z , electrodes type A for dry condition and
T
deviation factors F (5 % and 95 %) .49
D
Table A.2 – Total body impedances Z , electrodes type B for dry, water-wet and
T
saltwater-wet conditions and deviation factors F (5 % and 95 %) .49
D
Table A.3 – Total body impedances Z for dry, water-wet and saltwater-wet conditions
T
and deviation factors F (5 % and 95 %).50
D
Table A.4 – Deviation factors F (5 %) and F (95 %) for dry and water-wet conditions
D D
in the touch voltage range U = 25 V up to 400 V for large, medium and small surface
T
areas of contact .51
th
Table D.1 – 50 percentile values for the total body impedance for a current path
hands-feet medium surface area of contact for hands, large for feet, reduction factor
0,8, dry conditions, touch currents I and electrophysiological effects.56
T

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SIST-TS IEC/TS 60479-1:2006
– 6 – TS 60479-1 © IEC:2005
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

EFFECTS OF CURRENT ON HUMAN BEINGS
AND LIVESTOCK –

Part 1: General aspects


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.

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SIST-TS IEC/TS 60479-1:2006
TS 60479-1 © IEC:2005 – 7 –
IEC 60479-1, which is a technical specification, has been prepared by IEC technical
committee 64: Electrical installations and protection against electric shock.
This fourth edition cancels and replaces the third edition, published as a technical report in
1994, and constitutes a technical revision.
The main changes with respect to the previous edition are listed below:
th
– Dependence of the total body impedance Z for 50 percentile rank of a population of
T
living human beings for large, average and small surface areas of a contact in dry, water-
wet and saltwater-wet conditions at touch voltage U = 25 V to 200 V a.c. 50/60 Hz.
T
– Oscillograms of touch voltages U and touch currents I for a.c., current path hand-to-
T T
hand, large surface areas of contact in dry condition taken from measurements given in
Figure 16 with the relevant explanations in the main text.
– Fibrillation data for dogs, pigs and sheep obtained from experiments and for persons
calculated from statistics of electrical accidents with transversal direction of current flow,
hand-to-hand and touch voltages U = 220 V to 380 V a.c.with body impedances Z (5%)
T T
given in Figure 19 with the relevant explanations in the main text.
– Change of Curve B in Figure 20 from 10 mA to 5 mA: conventional time/current zones of
effects of a.c. current (15 Hz to 100 Hz) on persons with the relevant explanations in
themain text.
– Let-go currents for 60 Hz sinusoidal current given in Figure 23 with the relevant
explanations in the main text.
– new structure to the body of the standard.
This technical specification has the status of a basic safety publication in accordance with IEC
Guide 104.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
64/1427/DTS 64/1463/RVC

Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above Table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 60479 consists of the following parts under the general title Effects of current on human
beings and livestock
Part 1: General aspects
Part 2: Special aspects:
Chapter 4: Effects of alternating current with frequencies above 100 Hz
Chapter 5: Effects of special waveforms of current
Chapter 6: Effects of unidirectional single impulse currents of short duration
Part 3: Effects of currents passing through the bodies of livestock
Part 4: Effects of lightning strokes on human beings and livestock

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SIST-TS IEC/TS 60479-1:2006
– 8 – TS 60479-1 © IEC:2005
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The contents of the corrigendum of October 2006 have been included in this copy.

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SIST-TS IEC/TS 60479-1:2006
TS 60479-1 © IEC:2005 – 9 –
INTRODUCTION
This technical specification provides basic guidance on the effects of shock current on human
beings and livestock, for use in the establishment of electrical safety requirements.
In order to avoid errors in the interpretation of this specification, it must be emphasized that
the data given herein is mainly based on experiments with animals as well as on information
available from clinical observations. Only a few experiments with shock currents of short
duration have been carried out on living human beings.
On the evidence available, mostly from animal research, the values are so conservative that
the standard applies to persons of normal physiological conditions including children,
irrespective of age and weight.
There are, however, other aspects to be taken into account, such as probability of faults,
probability of contact with live or faulty parts, ratio between touch voltage and fault voltage,
experience gained, technical feasibilities, and economics. These parameters have to be
considered carefully when fixing safety requirements, for example, operating characteristics of
protective devices for electrical installations.
The form of the specification as has been adopted summarizes results so far achieved which
are being used by technical committee 64 as a basis for fixing requirements for protection
against shock. These results are considered important enough to justify an IEC publication
which may serve as a guide to other IEC committees and countries having need of such
information.
This technical specification applies to the threshold of ventricular fibrillation which is the main
cause of deaths by electric current. The analysis of results of recent research work on cardiac
physiology and on the fibrillation threshold, taken together, has made it possible to better
appreciate the influence of the main physical parameters and, especially, of the duration of
the current flow.
IEC 60479-1 contains information about body impedance and body current thresholds for
various physiological effects. This information can be combined to derive estimates of a.c.
and d.c. touch voltage thresholds for certain body current pathways, contact moisture
conditions, and skin contact areas. Information about touch voltage thresholds for
physiological effects is contained in the IEC 61201.
This specification refers specifically to the effects of electric current. When an assessment of
the harmful effects of any event on human beings and livestock is being made, other non-
electric phenomena, including falls, heat, fire, or others should be taken into account. These
matters are beyond the scope of this specification, but may be extremely serious in their own
right.
Recent research work has also been conducted on the other physical accident parameters,
especially the waveform and frequency of the current and the impedance of the human body.
This fourth revision of IEC 60479-1 should be viewed as the logical development and
evolution of the third edition.
Clause 2 of IEC 60479-1 (third edition) on the impedance of the human body contained little
information on the dependence of the impedance on the surface area of contact and then only
for dry conditions.

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SIST-TS IEC/TS 60479-1:2006
– 10 – TS 60479-1 © IEC:2005
Therefore measurements were carried out on 10 persons using medium and small surface
areas of contact in dry, water-wet and saltwater-wet conditions, current path hand to hand, at
a touch voltage of 25 V a.c. 50 Hz. The impedance values for a percentile rank of 5 %, 50 %
and 95 % have been calculated from these measurements.
Due to unpleasant sensations and the possibility of inherent danger, measurements using
2
large surface areas of contact (order of magnitude 10 000 mm ) in dry, water-wet and
saltwater-wet conditions and with medium and small surface areas of contact (order of
2 2
magnitude 1 000 mm and 100 mm ) in dry condition at touch voltages from 25 V up to and
including 200 V a.c. have only been carried out on one person. By the use of deviation factors
it was nevertheless possible to derive values of the total body impedance Z for a percentile
T
rank of 5 %, 50 % and 95 % of a population of persons. With the same one person
2
measurements were also made with still smaller surface areas of contact (10 mm and
2
1 mm ) and between fingertips.
For the calculation of total body impedance Z for a percentile rank of 5 %, 50 % and 95 % of
T
a population of persons for large surface areas of contact for touch voltages above 200 V up
to 700 V and higher up to the asymptotic values the method to adapt values of Z measured
T
on corpses to those of persons used for the second edition of IEC 60479-1 was improved by
taking account of the different temperature of the corpses during measurements and the
temperature of 37 °C for persons.
The present state of knowledge of a.c. impedance Z of the human body for large, medium
T
and small surface areas of contact in dry, water-wet and salt-water-wet conditions and of the
d.c.-resistance R of the human body for large areas of contact in dry conditions are
T
presented.
It should be mentioned that the thresholds as order of magnitude are valid for all persons
(men, women and children) independent of their state of health. Often concerns are
expressed in that respect but if the background of such objections is examined it is found that
such objections represent just opinions without experimental evidence. Some measurements
indicate that the thresholds of perception and let-go for women are lower than for men. This
may also be the case for children.
Furthermore in Clause 5 a heart-current factor F for the current path foot to foot has been
introduced. This is important for electrical risks caused by step voltages.

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TS 60479-1 © IEC:2005 – 11 –
EFFECTS OF CURRENT
...