Bsi bs en 60695 5 1 2003

BRITISH STANDARD BS EN 60695 5 1 2003 Fire hazard testing — Part 5 1 Corrosion damage effects of fire effluent — General guidance The European Standard EN 60695 5 1 2003 has the status of a British St[.]

Fire hazard testing —

The Eur opean Stand rd EN 6 6 5-5-1:20 3 has the status of a

BritishStand rd

ICS 2 0 0

Th is Br itish Stan ard was

publshed u der the authority

of the St an ards Polcy an

Strate y Commite on

2 Ju e2 0

© BSI 2 Ju e 0 3

ISBN 0 5 04 0 6 8

This British Stand rd is th e oficial Eng lish lang uag e v er ion of

EN6 6 5-5-1:20 3 It is identical with IEC6 6 5-5-1:20 2 It super ed es

BSEN6 6 5-5-1:19 3 which is withdrawn

The UK p rticip tion in its prep ration was entrusted to Tech ical Commit e

GEL/89, Fir e hazar d testing, which has the responsibi ty to:

A l st of org anizations represented on this commit e can be obtained on

request to its sec etary

Cros -referenc s

The British Stand rds which implement international or Eur opean

publ cations refer ed to in this document ma be fou d in the B SI Ca ta logue

u der the section entitled “ International Stand rds Cor espondence Index”, or

b using the “ Sear h” faci ty of the B SI Ele tr onic Ca ta l ogue or of

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contract User are responsible for its cor ect a plcation

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— aid enq uir er to u der tan d the tex t;

— present to the responsible international/European commit e any

enquiries on the interpretation , or proposals for change, and ke p the

UK interests informed ;

— monitor r elated inter national and European dev elopments an d

promulg ate them in the UK

Sum m ary ofpag es

This d ocument comprises a f ont cov er, an inside f ont cov er, the EN title p g e,

p ges 2 to 19 and a b ck cover

The BSI copy right d te display ed in this document ind icates when the

document was last is ued

Am endm ents is ued sinc publ cation

EUROPÄ ISCHE NORM February 2003

Euro e n Commite for Electrotec nic al St an ardiz at ion

Comité Euro é n de Normalsation Elec trotec hniq e

Euro äis hes Komite für Elek trot echnis he Normu g

Ce ntra l Secreta ria t: ru d Sta ssa rt 35, B - 105 0 Bru sels

© 2 0 CENELEC - A ll rig t s of e ploit at io in a y form a d b a y me n re erv ed worldwid for CENELEC memb rs

Es ais relat ifs aux risques du feu

Part ie 5-1: Efet s des dommages

de corosio d s efluent s du feu

-Guide général

(CEI 606 5-5-1:20 2)

Prüfungen z r Beurt eiung

der Brandg fa r

Tei 5-1: Kor osions c hädigung

durc h R auc h und/ oder Brandgase

-A llgemeiner Leitfaden

(IEC 60695-5-1:2002)

T his Euro e n Stan ard was a prov ed b CENELEC o 2 0 -0 -01 CENELEC memb rs are b u d to

comply wit h the CEN/ CENELEC Intern l Reg latio s which s p late t he con itio s for givin t his Euro e n

St an ard the st atus of a n tio al stan ard witho t a y alt erat io

Up-t o-d te lsts a d biblo ra hical refere ces concernin su h n t io al st an ards ma b o tain d o

a plcatio t o the Ce tral Sec retariat or to a y CENELEC memb r

This Euro e n St an ard e ists in thre oficial v rsio s (En lsh, Fre c , Germa ) A v rsio in a y other

la g a e ma e b t ra slatio u d r t he resp nsibi ty of a CENELEC memb r into its own la g a e a d

n t ifie to the Ce tral Secretariat h s t he same st atus as the oficial v rsio s

CENELEC memb rs are t he n t io al ele t rot ec hnic l c mmit tees of Aust ria, Belgium, Czech Rep blc ,

De mark, Finla d, Fra ce, Germa y, Gre ce, Hu g ry, Ic ela d, Irela d, Italy, L x mb urg, Malta,

Netherla ds, Norwa , Portug l, Slo a ia, Sp in, Swe e , Switz erla d a d United Kin d m

The tex t of doc ument 8 /5 6/FDIS, fut ure edit ion 2 of IEC 6 6 5-5-1, pre ared by IEC TC 8 , Fire

hazard t estin , was s bmitt d to the IEC-CENELEC p ralel vote an was a prov ed by CENELEC as

EN 6 6 5-5-1 on 2 0 -0 -01

This Euro e n Stan ard s p rsedes EN 6 6 5-5-1:19 3

The folowin dates were fix ed:

– latest date by whic h the EN has t o b implement ed

at national level by publc ation of an identical

– latest date by whic h the national st an ard c onflc t in

This Euro e n St an ard s ould b re d in conju ct ion w it h IEC 6 6 5-5-2 an IEC 6 6 5-5-3

An ex es desig at ed "normat iv e" are p rt of t he b d of t he st an ard

In t his st an ard, an e ZA is normat iv e

An e ZA has b en ad ed by CENELEC

Endorseme t not ic

The t ex t of t he Int ernat ional St an ard IEC 6 6 5-5-1:2 0 was a prov ed by CENELEC as a

Euro e n Stan ard w it hout an modificat ion

In t he oficial v ersion, for Biblogra h , t he folow in not e has t o b ad ed for t he st an ard in icat ed:

ISO 7 8 NOT E Harmo ize as EN ISO 7 8 :19 5 (n t mo ifie )

INTRODUCTION 4

1 Sco e 5

2 Normative ref eren es .5

3 Definition 6

4 Fire s enarios an f ire models 7

5 General asp cts of the cor osivity of f ire eff l ent 8

5.1 Cor osion damage s enarios 8

5.2 Typ s of cor osion damage ef fects .9

5.2.1 Metal los 9

5.2.2 Movin p rts b comin immo i e 9

5.2.3 Brid in of con u tor circ its 9

5.2.4 Formation of a non-con u tin layer on contact s r aces 9

5.3 Factors af fectin cor osivity .10 5.3.1 The nature of f ire eff l ent 10 5.3.2 The cor osion en ironment .1

6 Prin iples of cor osion damage me s rement .1

6.1 Introd ction .1

6.2 Generation of the f ire ef fluent .12 6.2.1 Selection of the test sp cimen whic is to b burned .12 6.2.2 Selection of the fire model 12 6.3 The as es ment of cor osive p tential 12 6.3.1 General .12 6.3.2 In irect as es ment .12 6.3.3 Simulated prod ct testin 13 6.3.4 Prod ct testin 13 6.4 Con ideration of cor osivity test method 14 7 Relevan e of data to hazard as es ment .16 An ex ZA (normative) Normative referen es to international publcation with their cor esp n in Euro e n publ cation 17 Bibl ogra h 19 Fig re 1 – Dif ferent stages in the develo ment of a fire within a comp rtment .8

Fig re 2 – Evaluation an con ideration of cor osion damage test method 15 Ta le 1 – General clas if i ation of fires (ISO/TR 912 -1) 8

Ta le 2 – Summary of cor osivity test method 13

INTRODUCTION

The ris of fire s ould b con idered in any electrical circ it With regard to this ris , the

circ it an eq ipment desig , the selection of comp nents an the c oice of materials s ould

contribute toward red cin the lkel ho d of f ire even in the event of f orese a le a normal

u e, malf un tion or fai ure The practical aim s ould b to prevent ig ition cau ed by electrical

malfu ction but, if ig ition an fire oc ur, to control the fire prefera ly within the b u d of the

en los re of the electrotec nical prod ct

Al fire ef f luent is cor osive to some degre an the level of p tential to cor ode de en s on

the nature of the fire, the combination of combu tible materials in olved in the f ire, the nature

of the s bstrate u der atac , an the temp rature an relative h midity of the en ironment in

whic the cor osion damage is takin place There is no eviden e that fire eff l ent f rom

electrotec nical prod cts of fers gre ter ris of cor osion damage than the f ire ef fluent f rom other

prod cts s c as f urnis in s, bui din materials, etc

The p r orman e of electrical an electronic comp nents can b ad ersely aff ected by

cor osion damage when s bjected to fire ef f luent A wide variety of combination of smal

q antities of ef fluent gases, smoke p rticles, moisture an temp rature may provide

con ition for electrical comp nent or s stem fai ures f rom bre kage, overhe tin or s ortin

Evaluation of p tential cor osion damage is p rtic larly imp rtant for hig value an saf

ety-related electrotec nical prod cts an in talation

Tec nical commite s resp n ible for the prod cts wi c o se the test s) an sp cify the level

of severity

The stu y of cor osion damage req ires an interdis iplnary a pro c in olvin c emistry,

electricity, ph sic , mec anical en ine rin , metal urg an electroc emistry In the

pre-p ration of this part of IEC 6 69 -5, al of the a ove have b en con idered

IEC 6 6 5-5-1 defines the s o e of the g idan e an in icates the field of a pl cation

IEC 6 6 5-5-2 provides a s mmary of test method in lu in relevan e an u ef ulnes

IEC 6 6 5-5-3 provides detais of a smal -s ale test method f or the me s rement of le kage

c r ent an metal los cau ed by fire ef fluent

a) general asp cts of cor osion damage test method ;

b) method of me s rement of cor osion damage;

c) con ideration of test method ;

d) relevan e of cor osion damage data to hazard as es ment

One of the resp n ibi ties of a tec nical commite is, wherever a plca le, to make u e of

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

2 Normative references

The f ol owin ref eren ed doc ments are in isp n a le f or the a plcation of this doc ment

For dated ref eren es, only the edition cited a pl es F r u dated ref eren es, the latest edition

of the referen ed doc ment (in lu in an amen ments) a pl es

IEC 6 6 5-1-1:19 9, Fire h z rd test ing – Part 1-1: Guid an e for a s s ing the fire h z rd

of el ectrotec nic l produ ts – Ge eral g id el i e

IEC/TS 6 6 5-5-2:2 0 , Fire h z rd te t in – Part 5-2: Coro ion dama e efe ts of fire

eflu nt – Summary a d relevan e of test methods

IEC/TS 6 6 5-5-3, Fire h z rd testing – P art 5-3: Coro ion d ama e efe ts of fire eflu nt –

L akag c r e t a d metal l os te t method

1

IEC 6 7 4-1:19 4, Te t o g s s evolved d uring c mb st io of materials fom c bl es –

Part 1: Determinat ion of t he amo nt of h log n a id g s

IEC 6 7 4-2:19 1, Te t o g s s evolv d d uring c mb st ion of ele tric c ble – P art 2:

Determination of d egre ofa id ity of g s s evolved during t he c mb st ion of mat erials tak en

fom el ectric c bl es b me s ring pH a d c nd uctivity

IEC 6 7 4-2, Amen ment 1 (19 7)

ISO/TR 912 -1:19 9, Toxicity test ing of fire eflu nts – P art 1: Ge eral

ISO 1 9 7-2:19 5, Pl astic – Smo e g n ratio – Determin t ion of the c ro ivity of fire

eflu nts – P art 2: St atic met hod

ISO 1 9 7-3:19 8, Pl astic – Smo e g n ratio – Determin t ion of the c ro ivity of fire

eflu nts – P art 3: Dy amic dec mp si tion method u in a travell ing furn c

_ _ _ _ _ _

1

To b p bls e

ISO 1 9 7-4:19 8, Pl astic – Smo e g n rat io – Det erminati on of the c ro ivity of fire

eflu nts – P art 4: Dy amic de omp sition method u ing a c nic l rad i ant h ater

ISO/IEC 13 4 :2 0 , Fire s fety – Vo a ulary

ASTM D 2 71 – 0 , St andard Te t Methods for He t-Shrinkabl e Tu ing for Elect ric l U se

cor osion target

sen or u ed to determine the degre of cor osion damage, u der specif ied con ition

NOT This s n or ma b a pro u t, a c mp n nt, or a refere c materialu e to simulate th m

[ISO/IEC 13 4 , def i ition 2 ]

3.3

critic l relativ h midity

level of relative h midity that cau es le kage c r ent to ex e d a value defined in the prod ct

f ire ef flue t de a c ara teristic

ph sical an /or c emical c an es in f ire eff l ent d e to time an tran p rt

detai ed des ription of con ition , in lu in en ironmental, of one or more stages f om b f ore

ig ition to after completion of combu tion in an actual fire at a sp cific location or in a re

l-s ale simulation

[ISO/IEC 13 4 , def i ition 5 ]

[ISO/IEC 13 4 , definition 15 ]

4 Fire scenarios and f ire models

Durin recent ye rs, major ad an es have b en made in the analy is of f ire eff l ents It is

recog ized that the comp sition of the mixture of combu tion prod cts is p rtic larly

de en ent up n the nature of the combu tin materials, the prevai n temp ratures an the

ventiation con ition , esp cial y ac es of ox gen to the se t of the fire Ta le 1 s ows how

the diff erent stages of a fire relate to the c an in atmosphere Con ition for u e in

la oratory s ale tests can b derived fom the ta le in order to cor esp n , as far as p s ible,

to ful s ale f ires

Fire in olves a complex an inter elated ar ay of ph sical an c emical phenomena As a

res lt, it is diff i ult to simulate al asp cts of a re l fire in la oratory s ale a p ratu This

pro lem of f ire model valdity is p rha s the sin le most p rplexin tec nical pro lem

as ociated with al f ire testin

General g idan e f or as es in the fire hazard of electrotec nical prod cts is given in

IEC 6 6 5-1-1

Af ter ig ition, fire develo ment may oc ur in diff erent way de en in on the en ironmental

con ition , as wel as on the ph sical ar an ement of the combu tible materials However, a

general p t ern can b esta l s ed for fire develo ment within a comp rtment, where the

general temp rature-time c rve s ows thre stages, plu a decay stage (se Fig re 1)

Stage 1 (non-f lamin decomp sition) is the in ipient stage of the fire prior to s stained

f lamin , with l t le rise in the fire ro m temp rature Ig ition an smoke generation are the

main hazard d rin this stage

Stage 2 (develo in f ire) starts with ig ition an en s with a ra id rise in f ire ro m

temp rature Spre d of f lame an he t rele se are the main hazard in ad ition to smoke

d rin this stage

Stage 3 (f ul y develo ed fire) starts when the s race of al of the combu tible contents of the

ro m has decomp sed to s c an extent that s d en ig ition oc urs al over the ro m, with a

ra id an large in re se in temp rature (flas over)

At the en of Stage 3, the combu tibles an /or ox gen have b en largely con umed an

hen e the temp rature decre ses at a rate whic de en s on the venti ation an the he t an

mas tran fer c aracteristic of the s stem This is k own as the decay stage

In e c of these stages, a diff erent mixture of decomp sition prod cts may b f ormed an

this, in turn, influen es the cor osive p tential of the fire ef fluent prod ced d rin that stage

Figure 1 – Dif f ere t sta e in the de elo me t of a fire within a compartme t

Table 1 – Ge eral cla sif ic tion of f ire (ISO/TR 9122-1)

Sta e 3 Fuly d v lo e f ire (lamin )

a) Relativ ly low v ntiatio 1 to 5 <10 6 0 to 9 0 4 to 7

b) Relativ ly hig v ntiatio 5 to 10 <10 6 0 to 1 2 0 5 to 15

* Ge eral e viro me tal c n itio (a era e) within c mp rtme t

* Me n v lu in f ire plumen ar to f ire

* * In id nt ir a ia c o to te t s e ime (a era e)

5 General aspe ts of the cor osivity of f ire ef f luent

5.1 Cor osion dama e s e arios

With resp ct to electrotec nical eq ipment an s stems, there are thre cor osion damage

s enarios whic are of con ern These are where cor osion damage is cau ed by f ire ef fluent

in the folowin situation :

a) within electrotec nical eq ipment an s stems when exp sed to fire ef fluent cau ed by

u u ual, local zed, internal sources of ex es ive he t an ig ition;

b) within electrotec nical eq ipment an s stems when exp sed to fire eff l ent cau ed by

external sources of flame or ex es ive he t;

c) within bui din stru tures when exp sed to f ire ef fluent emited f om electrotec nical

eq ipment an s stems

5.2 Type of cor osion dama e ef fe ts

Four typ s of cor osion damage efect are recog ized These are

a) metal los ,

b) movin p rts b comin immo i e,

c) brid in of con u tor circ its,

d) f ormation of a non-con u tin layer on contact s rf aces

5.2.1 Metal los

Metal los is cau ed by oxidation of elemental metal to a p sitive oxidation state One of the

simplest re ction of this typ is with an acid to f orm a metal salt an water, an this is wh

e rly ef f orts to comb t p tential cor osion were directed at red cin the acid gas prod ction

in fire ef f luent

However, it is not neces ary for an acid to b present for oxidation to oc ur If a metal is in

contact with an electricaly con u tive solution, the f re ion of the solution can faci tate

cor osion of contactin metals by either re ctin directly with the metal or by de olarizin the

are arou d the re ctin metal The rate of cor osion wi de en on the are of metal

af fected, the temp rature, an on the mag itu e of the dif feren e b twe n the electrode

p tentials of the oxidizin an red cin couples Metals hig er in the electroc emical series

are more prone to cor osion

Metal los can cau e man u desired eff ects In buidin s it can res lt in a we kenin or

fai ure of stru tural elements In electrical eq ipment it can cau e a decre se in electrical

con u tivity or ultimately the bre kin of a circ it

5.2.2 Movin parts be oming immobi e

Fire ef f luent can cau e movin p rts in mec anical or electromec anical eq ipment to

b come immo i e, e.g a b l b arin or p rts in a circ it bre ker This may b b cau e of the

de osition of stic y p rtic late mater or b cau e of the f ormation of c emical cor osion

prod cts b twe n s r aces

5.2.3 Bridgin of cond ctor circ its

Fire ef f luent may contain con u tive p rtic lates, e.g gra hitic carb n or ionic sp cies Metal

cor osion also prod ces ionic sp cies These con u tive sp cies can brid e the smal ga s

b twe n the co p r trac s on circ it b ard cau in u desired le kage c r ents This is of

p rtic lar con ern with digital telecommu ication eq ipment

5.2.4 Formation of a non-con ucting la er on conta t s rfa e

This is a p rtic lar case of metal los Cor osion at the interf ace of a metal contact can res lt

in the formation of a layer of non-con u tin material res ltin in the los of the circ it This is

p rtic larly l kely if the contact is b twe n dis imi ar metals b cau e they wi f orm an

electroc emical cel when in contact with a con u tive medium