Tiêu chuẩn iso 06184 4 1985 scan

P a rt 2: Determina tio of ex p losio in ic es of c omb ustib le ga ses in air.. The d sign of exp losio s p pres io s stems for ha za rds which ha v e exp losio pa ra meters signific an

,NT RA T,O AL OG NlZATlO FO STADR IZATIO ME)YAO~HR OrAH3Al&lR l0 CTAAPTM3AWWO GNlSTlO INT RA TIO AL DE N RMALISTIO

explosio s

De criptors : e plo io p ro fin , e plo io s pre sio s stems, te ts, efec tiven s

IS0 (h Interna tio a l O rga niza tio for Sta nda rdiza tio ) is a worldwid fe era tio of

na tio a l sta nda rds b dies (IS0 memb r b dies) T he work of pre a ring Interna tio a l

b dy intereste in a s bject for which a tech ic a l com ite ha s b e esta blsh d h s

me ta l a d n n-gov ernme ta l, in laiso with ISO , a lso ta ke pa rt in th work

Dra ft Interna tio a l Sta nda rds a o te by th tec hnic a l com ite s are circ ula te to

th memb r b dies for a pprov a l b fore th ir a cce ta nce a s Interna tio a l Sta nda rds by

th IS0 C ounc il T hey a re a pprov ed in a ccorda nce with IS0 proce ures re uiring a t

lea st 7 % a pprov a l by th memb r b dies v oting

Interna tio a l Sta nda rd IS0 616 /4 wa s pre are by Tec hnic a l Com ite ISO /T C 21,

Equipme t for fir e protectio a d fir e fighting

Users sh uld n te tha t al Interna tio a l Sta nda rds un ergo revisio from time to time

a nd- tha t a ny refere ce ma e h rein to a ny oth r Interna tio a l Sta nd rd imp lies its

la test e itio , unles oth rwise sta te

0 Interna tio a l O rga niza tio for Sta nda rdiza tio , 19 5 0

Printe in Switzerla nd

Explosion p r otec tion systems -

systems

0.1 Ex p losio s pp res io is a tech ique by which a d velo -

ing ex p losio in a c onfin d, or es e tially co fin d, volume is

d tecte a nd a rreste during its inc ip ie t sta ge, thu lm iting

pres ure d velop me t to a sa fe or p re etermin d va lue a nd

p reventing or minimizing da ma ge

The p rforma nce of a n ex plosio s p pres io s stem is a func -

a) th na ture a nd ex p losib ilty of th c ombu tible m er ial;

b ) th e viro me ta l c on itio s of temp era ture, p res ure,

turb ule c e, pro u t flow, etc ;

c ) th size a nd ge metry of th c onta in r;

e) th p erforma nc e c ha ra c teristic s of th ex p losio s p -

pres io ha rdwa re;

f th d ploy me t a nd ch ic e of ha rdwa re for th s stem

0.2 This p a rt of IS0 616 is o e of a series d a ling with ex -

p losio p rotec tio s stems The oth r p a rts a re a s folows :

P a rt 1: Determina tio of ex p losio in ic es of c omb ustib le

du ts in air

P a rt 2: Determina tio of ex p losio in ic es of c omb ustib le

ga ses in air

P a rt 3: Determina tio of exp losio in ic es of fuel/ air mix -

tures oth r tha n du t/ air a nd ga s/ air mix tures

0.3 It sh uld b recognize tha t th res lts ob ta in d from th

u e of th meth ds sp ec ifie in th oth r p a rts of IS0 616 ,

eith r by mea sureme t, inter p olatio or ex tra p ola tio , refer to

d fin d test c on itio s rep rese ting a ge eraliza tio of ty p ic al

op era tio a l c on itio s

The valdatio of th a p p lic a tio of a n ex p losio s pp res io

s stem for a p ar tic ular ha za rd ma y re uire furth r test work

a nd/or th oretic al eva lua tio Su h interp retatio a nd ap p iic a-

fie ld of ex p losio p rotec tio

The d sign of exp losio s p pres io s stems for ha za rds which

ha v e exp losio pa ra meters signific antly difer ent from th se

sp ec ia lists in this fie ld of ex p losio p rotec tio Exa mples of

s ch ha za rds a re th se c ha ra c terize by o e or more of th

folowing p a ra meters:

a) ves el a sp ct r atio grea ter tha n 2 : 1;

b ) p ar tially v ente ves els;

c ) c onta in r fite with fix ed or mob ile a ppa ra tu which

c ould imp ed th distr ib utio of s p res a nt;

d) op era ting pres ures a nd temp ra tures s b stantia lly

high r or lower tha n n rma l a tmosp eric c on itio s;

e) high levels of turb ule c e a nd/or p ro uc t throu h ut;

f v es el v olumes s b stantia lly grea ter or lower tha n th se

u e in th efic a c y test

This p art of IS0 616 sp ec ifies a meth d for ev a lua ting th ef

exp losio s in a n e close v olume It giv es th c r iter ia for alter -

na tive test a pp a ra tu u e to un erta ke ex p losio s pp res io

efic a c y tests a nd c r iter ia to b ap p lie in d fining th sa fe

op era ting regime of a n ex p losio s pp res io s stem

2 Field of ap p lic atio

This p art of IS0 616 is a p p lic a b le o ly to ex p losio s p pres-

sio s stems inte d d for th p rotec tio of close , or es e tia l-

ly c lose , ves els in which a n ex plosio ma y res lt a s a co se-

que ce of ignitio of a n ex p losive mix ture It d es n t a pp ly to :

m erials inse sitive to ignitio , exp losio a nd/or d to -

atio ;

b ) s stems or d v ices d sign d to p rotect a ga inst ov er-

p res ure of v es els c onta ining stea m, compres e ga ses,

lquifie d ga ses or unsta b le rea c ta nts;

c ) s stems or d v ices d sign d to protec t a ga inst ex oth r-

mic dis oc ia tio or p oly meriza tio rea c tio s;

galler ies;

e) s stems or d v ices d sign d sp ec ific ally for th purp se

of p rev entio of ignitio n of ex plosiv e mix tures

The d p loyme t of fir e p rotec tio mea sures, which a re outsid

th s o e of this p a rt of IS0 616 , ma y b n ces a ry after th

s p res io of th ex p losio to prev ent r eignitio in th p a r t of

th p lant co cern d

1

3 D e finitio s

F or th purp se of this Inter na tio al Sta nda rd, th d finitio s

given in pa rts 1, 2 a nd 3 of IS0 616 a nd th folowing d fini-

tio s a p p ly

3.1 s p p r es or : Ap p lia nc e c onta ining a n ex p losio s p -,

p res ure This p res ure ma y b store p res ure, or ma y b ob -

ta in d by a c hemic a l reac tio s ch a s th a c tivatio of a n ex -

p losive or py rotech ic d vic e

which, wh n disp erse into a c onta in r, ca n a rrest a d v elo

pres a nts a re in ge era l u e, sep a ra tely or in comb ina tio

(p owd r, wa ter, halo n)

a mmo ium p hosp a te, p ota ssium b ic a rb ona te or so ium b i-

improv e th ir flow p r op erties a nd th ir efec tiv en s

3.2.2 wa ter s p pres a nt: Wa ter u e a s a n ex p losio s p-

p res a nt Ad itives ma y b inc lud d to p rov id frost p rotec -

tio , a nd/or to imp rove th s p res a nt disp ersio p rop erties

rec ognize fla me ex ting ishing p rop erties s ch a s :

(y p ic ally nitr oge ) in a store p res ure-yp e s p res or

mea sure in b a r’)

sa nt c onta in d within th s p pres or mea sure in kiogra ms or

ltr e s

cha nges ca use by’a d velop ing ex p losio , in o e or more of

th e viro me ta l pa ra meters s ch a s pres ure, temp era ture

a nd/or r adia tio

3.6 ex p losio d tec tor: Dev ice or a rra ngeme t of a p pa r-

a tu , c onta ining o e or more ex p losio se sors, tha t resp n s

to a d velop ing ex p losio by p rov iding a n ex p losio s p res or

a c tua tio signa l

th pres ure a t ignitio of th rea c ta nts (p i), a t which a fir ing

signa l is ap p lie to th exp losio s p pres ors (se fig r e I)

pres ure, a bov e th p res ure a t ignitio of th rea cta nts (p i),

record d in a s p res e ex plosio ev ent (se fig r e 2)

in ge era l, th a ppa ra tu d sc rib ed in this p a rt of IS0 614 is

s itab le for th eva lua tio of th efic a c y of ex p losio s pp res-

sio s stems a ga inst ga s a nd du t ex p losio s

I

Time, t

p i

ig itio n

D etec tio

S up p re sio

F ig r e 1

1 1 b a r = 10 Pa

2

4.2 Test app ar a tu

4.2.1 A test to estab lish th efic a c y of a n ex p losio s pp res-

sio s stem shall b un erta ke in a test a p pa ra tu which gives

ob ta in d in th sta nda rd 1 m3 a ppa ra tu for th test combu t

ib le m a teria l

4.2.2 The 1 m3 test a p pa ra tu d sc rib ed in p a rts I2 a nd 3 of

IS0 616 is s ita b le for s pp res io s stem efic a c y tests with

a) th test v olume is o ly ap p rop ria te for th smaller ex-

b ) th py rotec hnic igniter s (otal e ergy 10 kJ) u e to

initiate du t exp losio s ca n tr i ger v ery se sitive d tec tors

p res ure s stems

4.2.3 The v olume of th test a p pa ra tu shall b s fic ie tly

pres or(s) a re re uire in ord r to attain a minimum d sign c on-

c entratio of s p pres a nt Sp heric a l or c y lin r ic al v es els with

a le gth to dia meter r atio les tha n 2 : 1a re p refere d signs

4.3.1 To d termin th efic a c y of a p artic ula r ex p losio s p-

p res io s stem a ga inst a d fin d ex p losive m a ter ial in a

ch se test volume, a single test is re uire The s pp res io

ex p losio pres ure & D shall b d termin d from th test

4.3.2 To d termin th ra nge of a p p lic a tio of a p artic ula r

ex p losio s p pres io s stem a ga inst ex p losio ha za rds in a

ch se test volume, a series of eva lua tio s shall b un erta ke

a ga inst ga s a nd du t ex p losio s of inc rea sing severity by va ry -

ing K (se fig re 2)

NO T E - The d tec tio pres ureP a nd th numb r of s p res ors a re

c onsta nt

4.3.3 To d termin th ra nge of a p p lic a tio of p artic ula r

p rforma nce shall b ev a lua te a ga inst ex plosio s of d fin d

severity , u ing a ra nge of d tec tio pres urespA (or e uiva le t

se sor resp nse; se fig re 3)

NO T E - The ex p losio in e K a nd th numb r of s p res ors a re

co sfa nt

4.3.4 To d termin th ra nge of a p p lic a tio of multip le ex -

p losio s p pres or c onfig ra tio s fite to large test v olumes,

th ir p rforma nce shall b ev a lua te a ga inst d fin d ex p losio

severities in th test v olumes (se fig r e 4)

NO T E - The ex plosio in ex K a nd th d tec tio p res ure pA a re

c onsta nt

Ex p losio s p res io efic a c y ev a lua tio s ca n b un erta ke

tising a lterna tive test e uipme t a nd/or test proce ures p ro-

vid d tha t it ha s b e prov en tha t s ch meth d logy giv es

r es lts com e s ra te with th se ob ta in d u ing th test p ro-

c edures d fin d in 4.3

s stem, a nd th minimum d sign stre gth of in u tr ial p lant to

which s ch a s stem ca n b a p p lie Tests in a ccorda nce with

th proce ures d sc rib d in sec tio 4.3.2 to 4.3.4 d termin th

ra nge of ap p lic atio of a n exp losio s pp res io s stem F rom

s ch tests it is p os ib le to a sc erta in

s p res a d fin d ex p losio ;

c ) th ap p lic ab ilty of test res lts to oth r volumes;

Go d

s p pres io

F aile s p pres io

t

K

F ig r e 2

PA

F ig r e 3

Numb er o f s p p re srs

F ig r e 4

6 Test r ep or t

The test rep ort sha ll inc lud th folowing inform io ;

a ) dime sio a l sk tch of th test a p p a ra tu ;

b ) test volume(s) u e ;

c l na ture of th ex p losive fuel(s) ;

dj exp losio in ic es of th fuel(s) a s sp ec ifie in p a rts 1,2

a nd 3 of IS0 616 ;

ej th initial pres ure pi;

test volume(s) ;

h) s pp res a nts);

resp nse) ;

k) s p res or p r op el ng a ge t p res ure(s) ;

m) s p res a nt c ha rge(s) in ea ch of th s p res ors;

p ) da te of test;

q) turb ule ce in e (ignitio n d la y ) t,

In a dditio , th r ep ort shall inc lud al p ertin nt o serv a tio s

a nd infor ma tio , which ma y n t b fuly d s rib d in a) to q)

a bov e Dev ia tio s from th d fin d test p roc edure a re p ermis -

ib le wh n n ces a ry, p rovid d tha t s ch d via tio s a re exa c tly

d sc rib d in th test rep ort

Test rep orts shall b c er tifie o b eha lf of th testing estab lish-