Iec Ts 60479-1-2016.Pdf

IEC TS 60479 1 Edition 4 1 201 6 07 CONSOLIDATED VERSION Effects of current on human beings and l ivestock – Part 1 General aspects IE C T S 6 0 4 7 9 1 2 0 0 5 0 7 + A M D 1 2 0 1 6 0 7 C S V (e n )[.]

IEC TS 60479- 1

Edit io 4.1 2 16-0

Efect s of cur ent on human beings and l v estock –

Part 1: General aspect s

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IEC TS 60479- 1

Edit io 4.1 2 16-0

Efect s of cur ent on human beings and l v est ock –

Part 1: General aspect s

BASIC SAFETY PUBLICATION

®

c olour

inside

IEC TS 60479- 1

Edit io 4.1 2 16-0

Efect s of cur ent on human beings and l v estock –

Part 1: General aspect s

BASIC SAFETY PUBLICATION

®

c olour

inside

CONTENTS

FOREWORD 6

INTRODUCTION 9

1 Sco e 1

2 Normative ref eren es 1

3 Terms an def i ition 12 3.1 General def i ition 12 3.2 Ef f ects of sin soidal alternatin c r ent in the ran e 15 Hz to 10 Hz 13 3.3 Ef f ects of direct c r ent 13 4 Electrical imp dan e of the h man b d 14 4.1 Internal imp dan e of the h man b d (Z i ) 14 4 2 Imp dan e of the s in (Z s ) 1

4 4.3 Total imp dan e of the h man b d (Z ) 15 4.4 F ctors af fectin initial resistan e of the h man b d (R 0 ) 15 4.5 Values of the total imp dan e of the h man b d (Z ) 15 4.5.1 Sin soidal alternatin c r ent 5 /6 Hz for large s rf ace are s of contact 15 4.5.2 Sin soidal alternatin c r ent 5 /6 Hz for medium an smal s rface are s of contact 18 4.5.3 Sin soidal alternatin c r ent with freq en ies up to 2 kHz 21

4.5.4 Direct c r ent 2

4.6 Value of the initial resistan e of the h man b d (R 0 ) 2

5 Ef f ects of sin soidal alternatin c r ent in the ran e of 15 Hz to 10 15 Hz 2

5.1 Thres old of p rception 2

5.2 Thres old of reaction 2

5.3 Immo i zation 2

5.4 Thres old of let-go 2

5.5 Thres old of ventric lar fibri ation 2

5.6 Other ef f ects related to electric s oc s 2

5.7 Ef f ects of c r ent on the s in 2

5.8 Des ription of time/c r ent zones (se Fig re 2 ) 2

5.9 Ap l cation of he rt-c r ent f actor (F) 2

6 Ef f ects of direct c r ent 2

6.1 Thres old of p rce tion an thres old of re ction 2

6.2 Thres old of immo i zation an thres old of let-go 2

6.3 Thres old of ventric lar fibri ation 2

6.4 Other ef f ects of c r ent 2

6.5 Des ription of time/c r ent zones (se Fig re 2 ) 2

6.6 He rt factor 2

6.7 Ef f ects of anodic vers s cathodic d.c c r ents 4

An exes 5

An ex A (normative) Me s rements of the total b d imp dan es Z T made on l vin h man b in s an on corpses an the statistical analy is of the res lts 51

An ex B (normative) In uen e of freq en y on the total b d imp dan e (Z ) 5

An ex E (inf ormative) The ries of ventric lar f ibri ation 6

An ex F (informative) Quantities ULV an L V 61

An ex G (inf ormative) Circ it simulation method in electric s oc evaluation 6

Fig re 1 – Imp dan es of the h man b d 2

Fig re 2 – Internal p rtial imp dan es Z ip of the h man b d 2

Fig re 3 – Simpl f ied s hematic diagram for the internal imp dan es of the h man b d 3

Fig re 4 – Total b d imp dan es Z (5 %) f or a c r ent p th han to han , for large s rf ace are s of contact in dry, water wet an saltwater wet con ition for a p rcenti e ran of 5 % of the p pulation for tou h voltages U T = 2 V to 7 0 V, a.c 5 /6 Hz 31

Fig re 5 – De en en e of the total imp dan e Z of one lvin p rson on the s rf ace are of contact in dry con ition an at tou h voltage (5 Hz) 3

Fig re 6 – De en en e of the total b d imp dan e Z on the tou h voltage U T f or a c r ent p th f rom the tips of the rig t to the lef t foref i ger comp red with large s rf ace are s of contact from the rig t to the lef t han in dry con ition me s red on one l vin p rson, tou h voltage ran e U T = 2 V to 2 0 V, a.c 5 Hz, d ration of c r ent f low max 2 ms 3

Fig re 7 – De en en e of the total b dy imp dan e Z f or the 5 th p rcenti e ran of a p pulation of lvin h man b in s f or large, medium an smal s rface are s of contact (order of mag itu e 10 0 0 mm 2 , 1 0 0 mm 2 an 10 mm 2 resp ctively) in dry con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz 3

Fig re 8 – De en en e of the total b d imp dan e Z f or the 5 th p rcenti e ran of a p pulation of lvin h man b in s f or large, medium an smal s rface are s of contact (order of mag itu e 10 0 0 mm 2 1 0 0 mm 2 an 10 mm 2 resp ctively) in water wet con ition at tou h voltages U T = 2 V to 2 0 V, a.c 5 /6 Hz 3

Fig re 9 – De en en e of the total b d imp dan e Z f or the 5 th p rcenti e ran of a p pulation of lvin h man b in s f or large, medium an smal s rface are s of contact (order of mag itu e 10 0 0 mm 2 , 1 0 0 mm 2 an 10 mm 2 resp ctively) in saltwater wet con ition at tou h voltages U T = 2 V to 2 0 V, a.c 5 /6 Hz 3

Fig re 10 – Values for the total b d imp dan e Z me s red on 10 l vin h man b in s with a c r ent p th han to han an large s rf ace are s of contact in dry con ition at a tou h voltage of 10 V an freq en ies from 25 Hz to 2 kHz 3

Fig re 1 – Values for the total b d imp dan e Z me s red on one l vin h man b in with a c r ent p th han to han an large s rf ace are s of contact in dry con ition at a tou h voltage of 2 V an freq en ies from 2 Hz to 2 kHz 3

Fig re 12 – Freq en y de en en e of the total b d imp dan e Z of a p pulation for a p rcenti e ran of 5 % f or tou h voltages from 10 V to 1 0 0 V an a f req en y ran e from 5 Hz to 2 15 kHz for a c r ent p th han to han or han to f oot, large s rf ace are s of contact in dry con ition 3

Fig re 13 – Statistical value of total b d imp dan es Z an b d resistan es R for

Fig re 18 – Trig erin of ventric lar fibri ation in the v lnera le p riod – Ef f ects on

electro-cardiogram (ECG) an blo d pres ure 4

Fig re 19 – Fibri ation data f or dog , pig an s e p from exp riments an for p rson calc lated from statistic of electrical ac idents with tran versal direction of c r ent f low han to han an tou h voltages U T = 2 0 V an 3 0 V a.c with b d imp dan es Z (5 %) 4

Fig re 2 – Con entional time/c r ent zones of eff ects of a.c c r ents (15 Hz to 10 Hz) on p rson for a c r ent p th cor esp n in to lef t han to f eet (for explanation se Ta le 1 ) 4

Fig re 21 – Os i ogram of tou h voltages U T an tou h c r ent I T f or d.c c r ent p th han to han , large s rf ace are s of contact in dry con ition 4

Fig re 2 – Con entional time/c r ent zones of ef f ects of d.c c r ents on p rson f or a lon itu inal upward c r ent p th (f or explanation se Ta le 13) 4

Fig re 2 – L t-go c r ents f or 6 Hz sin soidal c r ent 4

Fig re 2 – Ef f ects of anodic vers s cathodic d.c c r ents 4

Fig re 2 – Pulsed d.c stimulation of sin le he rt cel s 4

Fig re G.1 – Electric s oc in electrical model by Hart [3 ] in lu in startle re ction ef f ect 6

Bibl ogra h 6

Ta le 1 – Total b d imp dan es Z f or a c r ent path han to han a.c 5 /6 Hz, f or large s rf ace are s of contact in dry con ition 16 Ta le 2 – Total b d imp dan es Z f or a c r ent path han to han a.c 5 /6 Hz, f or large s rf ace are s of contact in water wet con ition 17 Ta le 3 – Total b d imp dan es Z f or a c r ent path han to han a.c 5 /6 Hz, f or large s rf ace are s of contact in saltwater wet con ition 18 Ta le 4 –Total b d imp dan es Z f or a c r ent p th han to han for medium s rf ace are s of contact in dry con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz (values rou ded to 2 Ω) 19 Ta le 5 – Total b d imp dan es Z f or a c r ent path han to han f or medium s rf ace are s of contact in water wet con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz (values rou ded to 2 Ω) 2

Ta le 6 – Total b d imp dan es Z f or a c r ent path han to han f or medium s rf ace are s of contact in saltwater wet con ition at tou h voltages U T = 2 Vto 2 0 Va.c 5 /6 Hz (values rou ded to 5 Ω) 2

Ta le 7 – Total b d imp dan es Z f or a c r ent path han to han f or smal s rf ace are s of contact in dry con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz (values rou ded to 2 Ω) 2

Ta le 8 – Total b d imp dan es Z f or a c r ent p th han to han f or smal s rf ace are s of contact in water wet con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz (values rou ded to 2 Ω) 21

Ta le 9 – Total b d imp dan es Z f or a c r ent p th han to han f or smal s rf ace are s of contact in saltwater wet con ition at tou h voltages U T = 2 V to 2 0 V a.c 5 /6 Hz (values rou ded to 5 Ω) 21

Ta le 10 – Total b d resistan es R T f or a c r ent p th han to han , d.c f or large s rf ace are s of contact in dry con ition 2

Ta le 1 – Time/c r ent zones f or a.c 15 Hz to 10 Hz f or han to feet p thway – Summary of zones of Fig re 2 2

Ta le A.1 – Total b d imp dan es Z , electrodes typ A f or dry con ition an

deviation factors F

D(5 % an 9 %) 51

Ta le A.2 – Total b d imp dan es Z , electrodes typ B for dry, water wet an

saltwater wet con ition an deviation f actors F

D(5 % an 9 %) 51

Ta le A.3 – Total b d imp dan es Z for dry, water wet an saltwater wet con ition

an deviation f actors F

D(5 % an 9 %) 51

Ta le A.4 – Deviation factors F

D(5 %) an F

D(9 %) for dry an water wet con ition

in the tou h voltage ran e U

T

= 2 V up to 4 0 V f or large, medium an smal s rface

are s of contact 5

Ta le D.1 – 5

th

p rcenti e values f or the total b d imp dan e f or a c r ent p th

han s-feet medium s rface are of contact for han s, large for f eet, red ction f actor

0,8, dry con ition , tou h c r ents I

T

an electro h siological ef f ects 5

Ta le G.1 – Bod imp dan e examples (u comp n ated) 6

INTERNATIONAL ELECTROTECHNICAL COMMISSION

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DISCLAIMER

This Con ol d te version is not a off icial IEC Sta dard a d ha be n prepare f or

us r conv nie c Only the c r e t v rsion of the sta dard a d its ame dme t(s)

are to be con idere the of ficial doc me ts

This Consol d te v rsion of IEC TS 6 4 9-1 be rs the e ition number 4.1 It consists of

conte t is id ntic l to th ba e e ition a d its ame dme t

In this Re l ne v rsion, a v rtic l l n in the margin s ows wh re the te h ic l conte t

The main tas of IEC tec nical commite s is to pre are International Stan ard In

ex e tional circ mstan es, a tec nical commit e may pro ose the publ cation of a tec nical

sp cif i ation when

• the req ired s p ort can ot b o tained for the publ cation of an International Stan ard,

despite re e ted ef f orts, or

• the s bject is sti u der tec nical develo ment or where, f or an other re son, there is the

f uture but no immediate p s ibi ty of an agre ment on an International Stan ard

Tec nical sp cif i ation are s bject to review within thre ye rs of publ cation to decide

whether they can b tran f ormed into International Stan ard

IEC 6 4 9-1, whic is a tec nical sp cif i ation, has b en pre ared by IEC tec nical

commite 6 : Electrical in tal ation an protection again t electric s oc

This f ourth edition can els an re laces the third edition, publs ed as a tec nical re ort in

19 4, an con titutes a tec nical revision

The main c an es with resp ct to the previou edition are l sted b low:

– De en en e of the total b d imp dan e Z

Tfor 5th

p rcenti e ran of a p pulation of

l vin h man b in s for large, average an smal s rf ace are s of a contact in dry, water

wet an saltwater wet con ition at tou h voltage U

han , large s rf ace are s of contact in dry con ition taken f rom me s rements given in

Fig re 16 with the relevant explanation in the main text

– Fibri ation data for dog , pig an s e p o tained f rom exp riments an for p rson

calc lated from statistic of electrical ac idents with tran versal direction of c r ent f low,

han -to-han an tou h voltages U

T

= 2 0 V to 3 0 V a.c.with b d imp dan es Z

T(5%)

given in Fig re 19 with the relevant explanation in the main text

– Chan e of Curve B in Fig re 2 from 10 mA to 5 mA: con entional time/c r ent zones of

ef f ects of a.c c r ent (15 Hz to 10 Hz) on p rson with the relevant explanation in

themain text

– L t-go c r ents f or 6 Hz sin soidal c r ent given in Fig re 2 with the relevant

explanation in the main text

– new stru ture to the b d of the stan ard

– Exten ion of the a plca i ty of the total b d imp dan e to a freq en y ran e up to

15 kHz;

– Clarif i ation of the dif f eren e in anodic vers s cathodic d.c pulses;

– Exten ion of the ventric lar fibri ation thres old of sin le pulses down to 1 µs pulse width;

– Addition of inf ormative an exes:

Annex E: The ries of ventric lar fibri ation;

Annex F: Quantities ULV an L V;

The text of this tec nical sp cif i ation is b sed on the f ol owin doc ments:

En uiry draft Re ort o v tin

Ful information on the votin f or the a proval of this tec nical sp cif i ation can b f ou d in

the re ort on votin in icated in the a ove Ta le

This publ cation has b en draf ted in ac ordan e with the ISO/IEC Directives, Part 2

IEC 6 4 9 con ists of the fol owin p rts u der the general title Effe ts of c r e t o h ma

b in s a d lv sto ck

Part 1: General asp cts

Part 2: Sp cial asp cts:

Cha ter 4: Ef f ects of alternatin c r ent with freq en ies a ove 10 Hz

Cha ter 5: Ef f ects of sp cial wavef orms of c r ent

Cha ter 6: Ef f ects of u idirectional sin le impulse c r ents of s ort d ration

Part 3: Ef f ects of c r ents p s in throu h the b dies of l vestoc

Part 4: Ef f ects of l g tnin strokes on h man b in s an l vestoc

The commit e has decided that the contents of the b se publ cation an its amen ment wi

"ht p:/ we store.iec.c " in the data related to the sp cifi publcation At this date, the

A bi n ual version of this publ cation may b is ued at a later date

The contents of the cor igen um of Octo er 2 0 an Ju e 2013 have b en in lu ed in this

co y

IMPORTANT – Th 'colour in ide' logo on the cov r pa e of this publ c tion indic te

that it contains colours whic are consid re to be us f ul f or the cor e t

understa ding of its conte ts Us rs s ould theref ore print this doc me t using a

colour printer

This b sic saf ety publcation is primariy inten ed f or u e by tec nical commite s in the

pre aration of stan ard in ac ordan e with the prin iples laid down in IEC Guide 10 an

ISO/IEC Guide 51 It is not inten ed for u e by man facturers or certifi ation b dies

One of the resp n ibi ties of a tec nical commit e is, wherever a pl ca le, to make u e of

b sic safety publ cation in the pre aration of its publ cation

This tec nical sp cif i ation provides b sic g idan e on the ef f ects of s oc c r ent on h man

b in s an lvestoc , for u e in the esta l s ment of electrical saf ety req irements

In order to avoid er ors in the interpretation of this tec nical sp cif i ation, it mu t s ould b

emphasized that the data given herein is mainly b sed on exp riments with animals as wel

as on information avaia le from cl nical o servation Only a few exp riments with s oc

c r ents of s ort d ration have b en car ied out on lvin h man b in s

On the eviden e avai a le, mostly from animal rese rc , the values are so con ervative that

the stan ard this doc ment a ples to p rson of normal ph siological con ition in lu in

c i dren, ir esp ctive of age an weig t

There are, however, other asp cts to b taken into ac ou t, s c as pro a i ty of f aults,

pro a i ty of contact with l ve or faulty p rts, ratio b twe n tou h voltage an fault voltage,

exp rien e gained, tec nical f easibi ties, an economic These p rameters have to s ould

b con idered caref ul y when f i in saf ety req irements, f or example, o eratin

c aracteristic of protective devices for electrical in tal ation

The f orm of the sp cif i ation doc ment as has b en ado ted s mmarizes res lts so f ar

ac ieved whic are b in u ed by tec nical commit e 6 as a b sis for f i in req irements

f or protection again t s oc These res lts are con idered imp rtant enou h to ju tif y an IEC

publ cation whic may serve as a g ide to other IEC commite s an cou tries havin ne d of

s c information

This tec nical sp cif i ation a pl es to the thres old of ventric lar f ibri ation whic is the main

cau e of de th by electric c r ent The analy is of res lts of recent rese rc work on cardiac

ph siolog an on the f ibri ation thres old, taken together, has made it p s ible to b ter

a preciate the in uen e of the main ph sical p rameters an , esp cial y, of the d ration of

the c r ent f low

IEC TS 6 4 9-1 contain information a out b d imp dan e an b d c r ent thres old for

variou ph siological eff ects This inf ormation can b combined to derive estimates of a.c

an d.c tou h voltage thres old f or certain b d c r ent p thway , contact moisture

con ition , and s in contact are s Information a out tou h voltage thres old f or

ph siological ef fects is contained in the IEC 612 1

This tec nical sp cif i ation refers sp cif i al y to the eff ects of electric c r ent When an

Clau e 2 of IEC 6 4 9-1 ( hird edition) on the imp dan e of the h man b d contained l t le

information on the de en en e of the imp dan e on the s rface are of contact an then only

f or dry con ition

Therefore me s rements were car ied out on 10 p rson u in medium an smal s rface

are s of contact in dry, water wet an saltwater wet con ition , c r ent p th han to han , at

a tou h voltage of 2 V a.c 50 Hz The imp dan e values f or a p rcenti e ran of 5 %, 5 %

an 9 % have b en calc lated f rom these me s rements

Due to u ple sant sen ation an the p s ibi ty of in erent dan er, me s rements u in

large s rface are s of contact (order of mag itu e 10 0 0 mm

) in dry con ition at tou h voltages f rom 2 V up to an

in lu in 2 0 V a.c have only b en car ied out on one p rson By the u e of deviation f actors

it was nevertheles p s ible to derive values of the total b d imp dan e Z

T

f or a p rcenti e

ran of 5 %, 5 % an 9 % of a p pulation of p rson With the same one p rson

me s rements were also made with sti smaler s rf ace are s of contact (10 mm

a p pulation of p rson f or large s rf ace are s of contact f or tou h voltages a ove 2 0 V up

to 7 0 V an hig er up to the as mptotic values the method to ada t values of Z

T

me s red

on corpses to those of p rson u ed f or the secon edition of IEC 6 4 9-1 was improved by

takin ac ou t of the dif ferent temp rature of the corpses d rin me s rements an the

temp rature of 3 °C f or p rson

The present state of k owled e of a.c imp dan e Z

T

of the h man b d for large, medium

an smal s rf ace are s of contact in dry, water wet an salt-water wet con ition an of the

d.c.- esistan e R

T

of the h man b d f or large are s of contact in dry con ition are

presented

It s ould b mentioned that the thres old as order of mag itu e are val d for al p rson

(men, women an c i dren) in e en ent of their state of he lth Of ten con ern are

expres ed in that resp ct but if the b c grou d of s c o jection is examined it is fou d that

s c o jection re resent ju t o inion without exp rimental eviden e Some me s rements

in icate that the thres old of p rce tion an let-go for women are lower than for men This

may also b the case f or c i dren

Furthermore in Clau e 5 a he rt-c r ent f actor F f or the c r ent p th f oot to f oot has b en

introd ced This is imp rtant f or electrical ris s cau ed by ste voltages

Further exp rimental data are u der con ideration, s c as recent on oin exp rimental work

on "c r ent in u ed he rt f ibri ation by ex itation with dis rete Fourier sp ctra" whic is

inten ed to contribute to f req en y factor data

EFFECTS OF CURRENT ON HUMAN BEINGS

Part 1: General aspects

For a given c r ent p th throu h the h man b d , the dan er to p rson de en s mainly on

the mag itu e an d ration of the c r ent f low However, the time/c r ent zones sp cif ied in

the f ol owin clau es are, in man cases, not directly a pl ca le in practice for desig in

me s res of protection again t electrical s oc The neces ary criterion is the admis ible l mit

of tou h voltage (i.e the prod ct of the c r ent throu h the b dy cal ed tou h c r ent an the

b d imp dan e) as a f un tion of time The relation hip b twe n c r ent an voltage is not

l ne r b cau e the imp dan e of the h man b d varies with the tou h voltage, an data on

this relation hip is theref ore req ired The dif ferent p rts of the h man b d (s c as the s in,

blo d, mu cles, other tis ues an joints) present to the electric c r ent a certain imp dan e

comp sed of resistive an ca acitive comp nents

The values of b d imp dan e de en on a n mb r of factors an , in p rtic lar, on c r ent

p th, on tou h voltage, d ration of c r ent f low, f req en y, degre of moisture of the s in,

s rf ace are of contact, pres ure exerted an temp rature

The imp dan e values in icated in this tec nical sp cifi ation res lt from a close examination

of the exp rimental res lts avai a le f rom me s rements car ied out prin ip l y on corpses

an on some lvin p rson

Knowled e of the ef fects of alternatin c r ent is primari y b sed on the fi din s related to the

ef f ects of c r ent at f req en ies of 5 Hz or 6 Hz whic are the most common in electrical

in tal ation The values given are, however, de med a plca le over the f req en y ran e

f rom 15 Hz to 10 Hz, thres old values at the l mits of this ran e b in hig er than those at

5 Hz or 6 Hz Prin ip l y the ris of ventric lar f ibri ation is con idered to b the main

mec anism of de th of fatal electrical ac idents

Ac idents with direct c r ent are mu h les f req ent than would b exp cted from the n mb r

of d.c a pl cation , an fatal electrical ac idents oc ur only u der very u f avoura le

con ition , for example, in mines This is p rtly d e to the f act that with direct c r ent, the l

et-go of p rts grip ed is les dif f ic lt an that f or s oc d ration lon er than the p riod of the

cardiac c cle, the thres old of ventric lar fibri ation is con idera ly hig er than f or alternatin

c r ent

NOT Th IEC 6 4 9 s rie c ntain informatio a o t b d imp d n e a d b d c re t thre h ld for v rio s

p y iolo ic l efe ts This inf ormatio c n b c mbin d to d riv e timate of a.c a d d.c to c v lta e

thre h ld for c rtain b d c re t p thwa s, c nta t moisture c n itio s, a d s in c nta t are s Informatio

a o t to c v lta ethre h ld for p y iolo ic l efe ts is c ntain d in IEC 612 1

con ition of the s in of a s rf ace are of contact with regard to h midity of a lvin p rson

b in at rest u der normal in o r en ironmental con ition

3.1.8

water-wet condition

con ition of the s in of a s rface are of contact b in exp sed for 1min to water of publc

water s p les (average resistivity ρ = 3 5 0 Ωcm, pH = 7 to 9)

3.1.9

s ltwater-wet con ition

con ition of the s in of a s rface are of contact b in exp sed for 1 min to a 3 % solution of

NaCl in water (average resistivity ρ = 3 Ωcm, pH = 7 to 9)

NOT It is a s me th t s ltwaterwet c n itio simulate th c n itio of th s in of a swe tin p rs n or a

p rs n after immersio in s awater Furth r in e tig tio s are n c s ary

3.1.10

de iation f actor

( )

TT

TT

TD

5 %,

%,

%,

UZ

UXZ

UX

3.2 Ef fe ts of sin soid l altern tin c r e t in the ra ge 15 Hz to 10 Hz

3.2.1

thre hold of perc ption

minimum value of tou h c r ent whic cau es an sen ation f or the p rson throu h whic it is

thre hold of v ntric lar fibri ation

minimum value of tou h c r ent throu h the b d whic cau es ventric lar f ibri ation

3.2.5

he rt c r e t f actor

F

relates the electric f ield stren th (c r ent den ity) in the he rt for a given c r ent p th to the

electric f ield stren th (c r ent den ity) in the he rt for a tou h c r ent of eq al mag itu e

f lowin f rom lef t han to f eet

NOT In th h art, th c re t d n ity is pro ortio al to th ele tric fieldstre gth

3.2.6

v lnerable period

comp ratively smal p rt of the cardiac c cle d rin whic the he rt f ibres are in an

in omogene u state of ex ita i ty an ventric lar f ibri ation oc urs if they are ex ited by an

electric c r ent of s f f icient mag itu e

NOT Th v ln ra le p rio c r e p n s to th first p rt of th T-wa e in th ele tro ardio ram whic is

a pro imately 10 %of th c rdia c cle (s e Fig re 17 a d 18)

k = 3,7

mA8

mA

3 0

.)s.m.(ofibri at i.c.a

ofibri at i.c.d

direct tou h c r ent throu h the h man b d for whic the feet re resent the negative p larity

4 Electrical impedance of the human body

The values of b d imp dan e de en on a n mb r of factors an , in p rtic lar, on c r ent

p th, on tou h voltage, d ration of c r ent f low, f req en y, degre of moisture of the s in,

s rf ace are of contact, pres ure exerted an temp rature

A s hematic diagram for the imp dan e of the h man b d is s own in Fig re 1

4.1 Internal impe a c of th huma body (Z

i)

The internal imp dan e of the h man b d can b con idered as mostly resistive Its value

de en s primari y on the c r ent p th an , to a les er extent, on the s rface are of contact

NOT 1 Me s reme ts in ic te th t asmal c p citiv c mp n nt e ists (d s e ln s in Fig re 1

Fig re 2 s ows the internal imp dan e of the h man b d f or its dif ferent p rts expres ed as

p rcentages of that related to the p th han to foot

For c r ent p th han to han or han to f eet, the imp dan es are mainly located in the

l mbs (arms an leg ) If the imp dan e of the tru k of the b d is neglected, a simpl f ied

circ it diagram can b esta l s ed whic is s own in Fig re 3

NOT 2 In ord r to simplfy th circ it dia ram, it is a s me th t th imp d n e of arms a d le s h v th s me

v lu s

4.2 Impe a c of the s in (Z

s)

The imp dan e of the s in can b con idered as a network of resistan es and ca acitan es

Its stru ture is made up of a semi-in ulatin layer an smal con u tive elements (p res) The

s in imp dan e f al s when the c r ent is in re sed Sometimes c r ent mark are o served

(se 4.7)

The value of the imp dan e of the s in de en s on voltage, f req en y, d ration of the c r ent

f low, s rf ace are of contact, pres ure of contact, the degre of moisture of the s in,

temp rature an typ of the s in

For lower tou h voltages the value of the imp dan e of the s in varies widely, even f or one

p rson, with s rf ace are of contact an con ition (dry, wet, p rspiration), temp rature, ra id

respiration, etc For hig er tou h voltages the s in imp dan e decre ses con idera ly an

b comes negl gible when the s in bre k down

As regard the in uen e of f req en y, the imp dan e of the s in decre ses when the

4.3 Total impe a c of th huma body (Z

T)

The total imp dan e of the h man b d con ists of resistive an ca acitive comp nents

For lower tou h voltages, there are con idera le variation in the imp dan e of the s in Z

S

an the total imp dan e of the h man b d Z

T

simi arly varies widely For hig er tou h

voltages, the total imp dan e de en s les an les on the imp dan e of the s in an its

value a pro c es that of the internal imp dan e Z

i Se Fig res 4 to 9

As regard the in uen e of freq en y, takin into ac ou t the f req en y de en en e of the

s in imp dan e, the total imp dan e of the h man b d is hig er for direct c r ent an

decre ses when the freq en y in re ses

4.4 Fa tors af f ecting initial re ista c of the huma body (R

0)

At the moment when the tou h voltage oc urs, ca acitan es in the h man b d are not

c arged Therefore s in imp dan es Z

S1

S2are negl gible an the initial resistan e R

0

is a proximately eq al to the internal imp dan e of the h man b d Z

i(se Fig re 1) The

initial resistan e R

0

de en s mainly on the c r ent p th an to a les er extent on the s rface

are of contact

The initial resistan e R

0

l mits the c r ent p ak of s ort impulses (e.g s oc s from electric

f en e control ers)

4.5 Value of the total impe a c of the huma b dy (Z

T)

The de en en e of the total b d imp dan e Z

T

f or the 5

th

p rcenti e ran of a p pulation of

l vin h man b in s f or large, medium an smal s rf ace are s of contact (order of mag itu e

resp ctively) in dry, water wet an saltwater wet

con ition at tou h voltages U

T

= 2 V a.c to 2 0 V a.c is s own in Fig res 7, 8 an 9

4.5.1 Sin soid l altern tin c r e t 5 /6 Hz f or larg s rf ac are s of conta t

The values of the total b d impedan es in Ta les 1, 2 an 3 are val d for l vin h man

b in s an a c r ent p th han to han for large s rface are s of contact (order of mag itu e

10 0 0 mm

2

) in dry (Ta le 1), water wet (Ta le 2) an saltwater wet (Ta le 3) con ition

The ran e of the total b d imp dan es for tou h voltages up to 7 0 V f or large s rface are s

of contact in dry, water wet an saltwater wet con ition f or a p rcenti e ran of 5 % of the

p pulation is presented in Fig re 4

The values for Ta les 1, 2 an 3 re resent the b st k owled e on the total b d imp dan es

Table 1 – Total body impe a c s Z

T

f or a c r e t path h nd to h nd a.c 5 /6 Hz, for

large s rf ac are s of conta t in dry con itions

T u h v ltage

V

Valu s for the total b dy impedanc s Z

T(Ω)that are n t exc eded for

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

NOT 3 For th sta d rd v lu of th v lta e 2 0 V (n twork-s stem 3N ∼ 2 0/4 0 V) it ma b a s me th t th

v lu s of th total b d imp d n e are th s me a for a to c v lta e of 2 5 V

NOT 4 Valu s of Z

Tare ro n e to 2 Ω

Table 2 – Total body impe a c s Z

T

f or a c r e t path h nd to h nd a.c 5 /6 Hz, for

large s rf ac are s of conta t in water-wet condition

T u h v ltage

V

Valu s for the total b dy impedanc s Z

T(Ω)that are n t exc eded for

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

NOT 3 For th sta d rd v lu of th v lta e 2 0 V (n twork-s stem 3N ∼ 2 0/4 0 V) it ma b a s me th t th

v lu s of th total b d imp d n e areth s me a for a to c v lta e of 2 5 V

NOT 4 Valu s of Z

T

are ro n e to 2 Ω

Table 3 – Total body impe a c s Z

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

The values in icated in Ta les 1 to 3 have b en derived from me s rements car ied out on

corpses an on l vin p rson (ad lts, males an f emales) as des rib d in An ex A

At voltages hig er than a proximately 12 V for water wet con ition an 4 0 V for saltwater

wet con ition the values f or the total b d imp dan e are the same as for dry con ition

de en only to a smal extent on the s rf ace are s of contact

However, when the s rf ace are of contact is very smal , in the order of a f ew s uare

mi imetres, the values are in re sed

Af ter the s in has broken down (for tou h voltages over a prox 10 V an af ter lon er

d ration of c r ent f low), the total b d imp dan e Z

on the s rf ace are of

contact for a.c 5 Hz in dry, water wet an saltwater wet con ition whic have b en car ied

tou h voltage ran e of 2 V to 2 0 V, a.c 5 Hz, me s red on one p rson is s own in

Fig re 5 For tou h voltages b low 10 V an smal s rface are s of contact in the order of a

f ew mm

2

, deviation in the me s rements can e si y re c a out + 5 % of the average,

de en in on temp rature, pres ure, location within the p lm of the han , etc

) on the tou h voltage for

a.c 5 /6 Hz for a voltage ran e f rom 2 V to 2 0 V is s own in Fig re 6

From Fig re 6 one can calc late that the p rtial imp dan e of one f oref i ger at a tou h

For a p rcenti e ran of 5 %, 5 % an 9 % of a p pulation of l vin h man b in s on the

k owled e at present avai a le the f ol owin presentation is given f or the total b d

• f or large s rf ace are s of contact, the values have b en presented in Ta les 1, 2 an

3 f or dry, water wet an saltwater wet con ition for tou h voltages U

T

= 2 V to

1 0 0 V, a.c 5 /6 Hz;

• f or medium s rf ace are s of contact, the values are presented in the f ol owin Ta les

4, 5 an 6 for dry, water wet an saltwater wet con ition for tou h voltages U

T

= 2 V

to 2 0 V a.c 5 /6 Hz;

• f or smal s rf ac are s of c nta t, the values are presented in the fol owin Ta les 7, 8

an 9 f or dry, water wet an saltwater wet con ition f or tou h voltages U

are s of conta t in dry conditions at touc volta e U

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

Table 5 – Total body impe a c s Z

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

Table 8 – Total body impe a c s Z

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

4.5.3 Sin soid l alternating c r e t with f re ue cie up to 2 kHz

The values of the total b d imp dan e f or 5 /6 Hz decre se at hig er f req en ies d e to

the in uen e of the ca acitan es of the s in an a pro c , f or f req en ies a ove 5 kHz, the

internal b d imp dan e Z

i

The me s rements of the total b d imp dan e with freq en ies up to 2 kHz at tou h

voltages of 10 V an 2 V are des rib d in An ex B

alternatin c r ent f or tou h voltages up to a proximately 2 0 V d e to the bloc in ef f ect of

the ca acitan es of the h man s in

The me s rements of the total b d imp dan e whic have b en car ied out with direct

c r ent f or large s rface are s of contact in dry con ition are des ribed in An ex C

NOT No me s reme ts h v b e c rie o t in waterwet a d s ltwaterwet c n itio s

The values f or the total b d resistan e R

Tfor direct c r ent determined in the way des rib d

in An ex C are presented in Ta le 10 (se Fig re 13, contin ou l nes)

For large s rface are s of contact in water wet an saltwater wet con ition the total b d

resistan e R

Tmay b determined with s f f icient ac urac f rom Ta les 2 an 3, whi e

neglectin smal dif feren es of Z

T

b twe n a.c an d.c whic may exist in the voltage ran e

b low 10 V For al other cases, the ta les for a.c can b u ed for a con ervative estimate

Table 10 – Total bod re ista c s R

Tfor a c r e t path ha d to ha d, d.c

for large s rf ac are s of conta t in dry conditions

T u h v ltage

V

Valu s for the total b dy re istanc R

T(Ω) that are n t exc eded for

5 % of the p pulatio 5 % of the p pulatio 9 % of the p pulatio

NOT 3 Valu s of R

Tare ro n e to 2 Ω

4.6 Value of the initial re ista c of the huma body (R

0)

The value of the initial resistan e of the h man b d R

0for a c r ent p th han to han or

han to foot an large s rface are s of contact can b taken as eq al to 5 0 Ω for a

p rcentie ran of 5 % f or a.c an for d.c The values for 5 % an 9 % of the p pulation can

b taken as eq al to 7 0 Ω an 1 0 0 Ω resp ctively (simi ar to Ta le 1) The values de en

only l tle on the s rface are s of contact an on con ition of the s in

NOT Th v lu s for initial re ista c R

0are s mewh t lower th n th a ymptotic v lu s for th total b d

imp d n e Z

Tfor a.c 5 /6 Hz a d th total b d re ista c R

T

f or d.c b c u e wh n c nta t is ma e th

c p cita c s of th s in a d th intern l c p cita c of th b d are u c arg d

5 Ef f ects of sinusoidal alternating cur ent in the ra ge of 15 Hz to 10 150 Hz

This Clau e 5 des rib s the ef fects of sin soidal alternatin c r ent p s in throu h the

h man b d within the freq en y ran e 15 Hz to 10 15 Hz

NOT Unle s oth rwis s e ifie , th c re t v lu s d f i e h rein fter are r.m.s v lu s

Examples of tou h c r ents an their ef f ects are s own in Fig re 2

5.1 Thre hold of perc ption

The thres old de en s on several p rameters, s c as the are of the b d in contact with an

electrode (contact are ), the con ition of contact (dry, wet, pres ure, temp rature), an also

on the ph siological c aracteristic of the in ivid al

5.2 Thre hold of re ction

The thres old de en s on several p rameters, s c as the are of the b d in contact with an

electrode (contact are ), the con ition of contact (dry, wet, pres ure, temp rature), an also

on the ph siological c aracteristic of the in ivid al

A value of 0,5 mA in e en ent of time, is as umed in this tec nical sp cif i ation f or the

thres old of re ction when tou hin a con u tive s rf ace

5.3 Immobi zation

Immo i sation in this doc ment me n the ef fect of electric c r ent s c that the b d of the

in uen ed h man b in (or p rt of the b d ) can ot move volu tari y

The ef f ect on mu cles may res lt f rom c r ent f lowin throu h the af f ected mu cles or

throu h as ociated nerves or the as ociated p rt of the brain

The values of c r ent whic cau e immo i sation de en on the volume of the mu cles

af f ected, the typ of nerve an the p rts of the brain af fected by the c r ent

5.5 Thre hold of v ntric lar f ibri lation

The thres old of ventric lar f ibri ation de en s on ph siological p rameters (anatomy of the

b d , state of cardiac f un tion, etc.) as wel as on electrical p rameters (d ration an

p thway of c r ent f low, c r ent c aracteristic, etc.) A des ription of he rt activity is given in

Fig res 17 an 18

With sin soidal a.c (5 Hz or 6 Hz), there is a con idera le decre se in the thres old of

f ibri ation if the c r ent flow is prolon ed b yon one cardiac c cle This ef fect res lts from

the in re se in in omogeneity of the ex itatory state of the he rt d e to the c r ent in u ed

extra-s stoles

For s oc d ration b low 0,1 s, f ibri ation may oc ur f or c r ent mag itu es a ove 5 0 mA,

an is l kely to oc ur for c r ent mag itu es in the order of several amp res, only if the s oc

f al s within the v lnera le p riod For s oc s of s c inten ities an d ration lon er than one

cardiac c cle reversible cardiac ar est may b cau ed

For d ration of c r ent f low lon er than one he rt p riod Fig re 19 s ows a comp rison

b twe n the thres old of ventric lar f ibri ation from animal exp riments an f or h man

b in s calc lated from statistic of electrical ac idents

In ada tin the res lts from animal exp riments to h man b in s, an empirical c rve c

1(se

Fig re 2 ) was con entional y esta l s ed f or a c r ent p th lef t han to b th f eet, b low

whic f ibri ation is u l kely to oc ur The hig level f or s ort d ration of exp s re b twe n

10 ms an 10 ms was c osen as a des en in l ne f rom 5 0 mA to 4 0 mA On the b sis of

information on electrical ac idents, the lower level for d ration lon er than 1 s was c osen

as a des en in l ne from 5 mA at 1 s to 4 mA f or d ration lon er than 3 s Both levels

were con ected by smo th c rves

By statistical evaluation of animal exp riments, c rve c an c rve c (se Fig re 2 ) have

b en esta l s ed def i in a pro a i ty of f ibri ation of a out 5 % an 5 % resp ctively

Curves c

1, c an c a ply f or c r ent p th lef t han to b th feet

5.6 Oth r ef f ects relate to ele tric s oc s

Other electrical ef f ects s c as mu c lar contraction , rise in blo d pres ure, disturb n es of

f ormation an con u tion of cardiac impulses (in lu in atrial f ibri ation an tran ient rh thm

disturb n es) may oc ur Su h ef fects are not generaly lethal

With c r ents of several amp res lastin more than secon s, de p-se ted burn , an other

internal injuries, may oc ur Surface burn may also b se n

Hig voltage ac idents may not res lt in ventric lar f ibri ation, in te d givin other f orms of

cardiac ar est This is s own in ac ident statistic an con rmed by animal exp riments

However there is at present in uf f icient data to diff erentiate the l kelho d of these con ition

Ventric lar fibri ation is f atal b cau e it denies blo d f low whic tran p rts req ired ox gen

Electrical ac idents that do not in olve ventric lar f ibri ation can also b f atal Other ef fects

may af f ect respiration an mig t prevent the p rson from s outin f or help These related

mec anisms in lu e fun tional disturb n e of respiratory control, p raly is of respiratory

mu cles, damage to the neural activation p thway f or these mu cles, an damage to the

respiratory control mec anism within the brain tem These ef fects, if p rmanent, le d

inevita ly to de th If a p rson is to recover from a reversible respiratory ef f ect, prompt

artif i ial respiration is man atory Nonetheles , the p rson may sti die If c r ent f lows

throu h critical p rts s c as the spinal cord or the respiratory control centre, de th can

hig -mag itu e, s ort-d ration b d c r ents (s c as f rom momentary contact with hig

-voltage p wer distribution l nes) A hig electric field acros cel membranes can in u e the

f ormation of p res in the membranes The ef f ect is caled electro oration The p res may b

sta le an ultimately se l over, or may enlarge, b come u sta le, an s bseq ently cau e

rupture of the cel membranes Tis ue then b comes ir eversibly damaged Necrosis of the

tis ue can oc ur, of ten req irin amputation of injured l mbs Electro oration is not l mited to

an p rtic lar c r ent mag itu e or to an p rtic lar c r ent p thway or d ration of f low

Related non-electrical injuries, s c as traumatic injury, s ould b con idered

, in general no c an es to the s in are o served For lon er

d ration of c r ent f low (several secon s) the s in b low the electrode may b of

greyis -white colour with a co rse s rface (zone 0);

2

2

, a red enin of the s in oc urs with a wave lke

swel n of whitis colour alon the ed es of the electrode (zone 1);

2

2

, a brownis colour develo s b low the electrode

exten in into the s in F r lon er d ration of c r ent f low (several ten of secon s)

f ul c r ent mark (blsters) are to b o served arou d the electrode (zone 2);

2

, carb nization of the s in can oc ur (zone 3);

• with large contact are s c r ent den ities may b low enou h not to cau e an

alteration of the s in in spite of f atal c r ent mag itudes

5.8 De cription of time/c r e t zone (s e Figure 2 )

Table 1 – Time/c r e t zon s for a.c 15 Hz to 10 Hz f or ha d to f eet pathwa –

Summary of zone of Figure 2

Perc ptio a d in olu tary mu c lar c ntra tio s lk ly b t u u ly n h rmf ul

ele tric l p y iolo ic l ef fe ts

a o e

Stro gin olu tary mu c lar c ntra tio s Dif fic lty in bre thin Re ersible

disturb n e of h art fu ctio Immo i z tio ma o c r Eff ects in re sin

with c re t ma nitu e Us aly n org nic d ma e to b e p cte

A -4 1

Ab v c rv

c

1

Path -p y iolo ic l efe ts ma o c r s c a c rdia are t, bre thin are t,

a d b rn or oth r c lular d ma e Pro a i ty of v ntric lar fibri atio

in re sin with c re t ma nitu e a d time

5.9 Appl c tion of he rt c r e t f actor (F)

The he rt-c r ent f actor p rmits the calc lation of c r ents I

NOT Th h art-c re t fa tor is to b c n id re a o ly a ro g e timatio of th relativ d n er of th v rio s

c re t p th with re ard to v ntric lar f i ri atio

For dif ferent c r ent p th , the fol owin he rt-c r ent factors are given in Ta le 12

Table 12 – He rt c r e t f actor F f or dif f ere t c r e t paths

NOT 1 Th term "dire t c re t" me n rip le- e dire t c re t Howe er, a re ard fibri atio efe ts, th

d ta giv n in this cla s are c n id re to b c n erv tiv for dire t c re ts h vin a sin s id l rip le c nte t of

n t more th n 10 % r.m.s

NOT 2 Th influ n e of ip le is d alt with in c a ter 5 of IEC 6 4 9-2

NOT 3 For d ratio s of c re t f l w b low 10 ms s e c a ter 6of IEC 6 4 9-2

An example of a tou h c r ent an its ef f ects are s own in Fig re 21

6.1 Thre hold of perc ption a d thre hold of re ction

These thres old de en on several p rameters, s c as the contact are , the con ition of

contact (dry es , wetnes , pres ure, temp rature), the d ration of c r ent f low an on the

6.2 Thre hold of immobi zation a d thre hold of let go

Unl ke a.c there is no def i a le thres old of immo i zation or let-go f or d.c Only makin an

bre kin of c r ent le d to p inf ul an cramp-lke contraction of the mu cles

6.3 Thre hold of v ntric lar f ibri lation

As des rib d for a.c (se 5.5), the thres old of ventric lar f ibri ation in u ed by d.c de en s

on ph siological as wel as on electrical p rameters

Inf ormation derived f rom electrical ac idents se ms to in icate that the dan er of ventric lar

f ibri ation general y exists f or lon itu inal c r ents For tran verse c r ents, exp riments on

animals have, however, s own that at hig er c r ent inten ities ventric lar f ibri ation may

also oc ur

Exp riments on animals as wel as inf ormation derived from electrical ac idents s ow that the

thres old of f ibri ation for a downward c r ent is a out twice as hig as for an upward c r ent

For s oc d ration lon er than the cardiac c cle, the thres old of f ibri ation f or d.c is

several times hig er than for a.c F r s oc d ration s orter than 2 0 ms, the thres old of

f ibri ation is a proximately the same as for a.c me s red in r.m.s values

Curves derived from animal exp riments have b en con tru ted that a ply to lon itu inal,

upward (feet p sitive) c r ent Curves c an c in Fig re 2 s ow the calc lated

combination of c r ent mag itu e an d ration at whic the pro a i ties of ventric lar

f ibri ation of the animals are a out 5 % an 50 % resp ctively when the c r ent p th is

lon itu inal throu h the b d (i.e lef t f oreleg to b th hin leg ) Curve c

1

s ows c r ent an

d ration combination b low whic the l kel ho d of ventric lar fibri ation is estimated to b

very low f or the same lon itu inal p thway of c r ent throu h the b d b sed on the animal

stu ies L ter stu ies s ow that the ventric lar fibri ation thres old f or h man is hig er than

the c r ent mag itu e as comp red to the animals for e c d ration F r example, the lef t

han to f eet thres old c r ent f or a he lth h man mig t b in the order of 2 0 mA f or lon

d ration of c r ent However, not al h man he rts are he lth , an some maladies can

af f ect the ventric lar f ibri ation thres old Some p o le with u he lth he rt con ition have

ventric lar fibri ation thres old b low normal, but the amou t of the red ction is not

precisely k own Therefore, it is recommen ed that the c

1

l ne s own in the f i ure that is

b sed on animal stu ies, b u ed to des rib the ventric lar fibri ation thres old f or h man

as a con ervative estimate There are no k own electrical ac idents that s ow an

electroc tion b low the c

1

c rve This in icates that the c

1

c rve is pro a ly con ervative for

al h man For lon itu inal downward c r ent (feet negative), the c rves have to b s if ted

to a hig er c r ent mag itu e by a factor of a proximately 2

6.4 Oth r ef fe ts of c r e t

Ab ve a proximately 10 mA, a sen ation of warmth may b f elt in the extremities d rin

c r ent-f low Within the contact are , p inful sen ation are f elt

6.5 De cription of time/c r e t zone (s e Figure 2 )

Table 13 – Time/c r e t zone f or d.c for ha d to f eet pathwa –

Summary of zone of Figure 2

In olu tary mu c lar c ntra tio s lk ly e p cialy wh n ma in , bre kin or

ra idly alterin c r e t f l w b t u u ly n h rmful ele tric l p y iolo ic l

efe ts

a o e

Stro g in olu tary mu c lar re ctio s a dre ersible disturb n e of

formatio a d c n u tio of imp ls s in th h art ma o c r, in re sin with

c re t ma nitu e a d time Us aly n org nic d ma e to b e p cte

D -4 1

1

Path -p y iolo ic l ef fe ts ma o c r s c a c rdia are t, bre thin

are t, a d b rn or oth r c lular d ma e Pro a i ty of v ntric lar

fibri atio in re sin with c re t ma nitu e a d time

c

1-c D -4.1 Pro a i ty of v ntric lar fibri atio in re sin u to a o t 5 %

c -c D -4.2 Pro a i ty of v ntric lar fibri atio u to a o t 5 %

Be o d c rv c D -4.3 Pro a i ty of v ntric lar fibri atio a o e 5 %

1

For d ratio s of c re t f l w b low 2 0 ms, v ntric lar f i ri atio is o ly initiate within th v ln ra le p rio if

th rele a t thre h ld are s rp s e As re ard v ntric lar fibri atio this f i ure relate to th efe ts of c re t

whic f l ws in th p th left h n to fe t a d for u ward c re t For oth r c re t p th th h art c re t fa tor h s

ip/ 5

intern l p rtial imp d n e of o e e tremity (arm or le )

NOT Th intern l imp d n e fom o e h n to b th fe t is a pro imately 7 %, th imp d n e fom b th h n s

to b th fe t 5 % a d th imp d n e fom b th h n s to th tru k of th b d 2 % of th imp d n e h n to h n

or h n to fo t

Figure 3 – Simpl fie s hematic diagram f or the internal impe a c s of the huma body

3

IEC 9 8 3 /05

Ke

1 dry c n itio s (Ta le1

2 water wet c n itio s (Ta le 2)

3 s ltwater wet c n itio s (Ta le 3)

Fig re 4 – T tal body impe a c s Z

T(5 %) f or a c r ent path ha d to h nd, f or large

s rf ac are s of conta t in dry, water-wet a d s ltwater-wet condition for a perce ti e

ra k of 5 % of th population for touc volta e U

T

= 2 V to 7 0 V, a.c 5 /6 Hz

),c r e t p th fom th tip of th rig t to left f orefin er

Fig re 6 – Depe de c of the total body impe a c Z

T

on the touc volta e U

T

for a c r e t path f rom th tips of th right to the lef t f oref inger compare

with large s rf ac are s of conta t f rom the rig t to the lef t ha d in dry condition

me s re on on l ving person, touc volta e ra ge U

T

= 25 V to 2 0 V, a.c

5 Hz, duration of c r e t flow ma 2 ms