BRIEF REVIEW ON FORCED-VENTILATION REQUIREMENTS IN CHINA FIRE CODES

Transcription

1 Inernainal Jurnal n Engineering Perfrmance-ased Fire des, Vlume 5, Number, p.7-9, RIEF REVIEW ON FORE-VENTILTION REQUIREMENTS IN HIN FIRE OES Qia Kui eparmen f uilding Services Engineering, Te Hng Kng Plyecnic Universiy, Hng Kng, ina (Received 9 January ; cceped Marc ) STRT Smke cnrl sysems are required in many buildings in ina. des and requiremens n frced venilain insallains relaed smke cnrl sysem in ina are reviewed in is paper. Key parameers are discussed and cmpared se fr cdes in Hng Kng. Example cases n an undergrund carpark and a single rm in a all building are used fr illusraing e requiremens. Simulains wi fire mdels FIREWIN will be carried u jusify e design fllwing e cdes.. INTROUTION nsequen jining e Wrld Trade Organizain, i is ineresing inrduce e fire safey cde sysem in ina. In fac, researc and develpmen aciviies n fire were carried u acively in e pas 5 years. Tis as becme an impran field in engineering fr suppring fire cdes sysem in ina. Te fire safey sysem iself is quie cmplicaed and can be classified eier by legal aspecs r by ecnical specificain issued by differen gvernmen deparmens frm Nainal Peple s ngress lcal gvernmens. summary car is swn in Table. Many fire cdes are relaed buildings, ree cmmnly used are: de fr fire precin design f indusrial buildings, sres and general aparmens (GJ-6-87, 995) [5]; de fr fire precin design f all buildings (G545-95, 997) [6]; and esign cde fr residenial buildings (G596, 999) [4]. Tere are far many iems discuss n acive fire precin sysem, and passive building cnsrucin. In is paper, nly e frced venilain sysems in buildings are fcused. Te bjecive f is researc is use fire mdels evaluae e requiremens f frced venilain in ina fire cdes. Perfrmance f smke exracin sysem was sudied verify e necessary ime fr evacuain.. OJETIVES OF INSTLLING VENTILTION SYSTEM IN UILING Frced venilain sysem insalled in a building includes fans, venilain pumps, pressurizain sysems, inles and ules f venilain. Smke exracin sysems serve preven smke spreading sme criical areas, reduce e smke emperaure and imprve visibiliy by aking acin suc as diluing e smke wi fres air [-]. One r mre f e fllwing bjecives [-] mus be saisfied by insalling venilain cnrl sysem and smke cnrl sysem: Mainaining a enable envirnmen in e means f egress in large-vlume building spaces during e evacuain ime. nrlling and reducing e migrain f smke beween e fire area and adjacen spaces. Prviding cndiins wiin and uside e fire zne a will assis emergency respnse persnnel cnduc searc and rescue perain, and lcae and cnrl e fire. nribuing e precin f life and reducin f prpery lss. Invlving in smke remval fr a psflasver fire. T acieve ese bjecives, smke exracin sysems and saircase pressurizain sysems are insalled in ms f e cmmercial buildings, residenial buildings and indusrial buildings in ina Mainland [4-8]. 7

2 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Table : lassificain f fire cdes in ina Issued by Legal aspecs Tecnical specificain Legislaive Fire de dminisraive Fire de Nainal Peple s ngress Sae uncil Minisry f Public Securiy Oer Minisries (e.g. Minisry f nsrucin) Lcal gvernmens Minisry f Public Securiy Minisry f nsrucin Lcal gvernmens Fire Law f ina Penal Law f ina Punismen Regulain dminisraive Prcedural Law iy Planning Law, ec. dminisraive Fire de Fire cde f Managemen and dminisrain uilding Fire dminisraive Regulain, ec. Lcal Fire de Tecnical Law iy Planning Regulains esign de fr Residenial uildings de fr Fire Precin esign f uildings, ec. Tere are w ypes f smke exracin sysem: ynamic smke exracin sysem ynamic sysem is a mecanical venilain sysem capable f remving smke including cmbusin prducs frm e fire cmparmen, and als supplying in fres air mainain a specified smke-free zne belw e smke layer. Saic smke exracin sysem Saic sysem as been applied in naural venilain, uilizing smke reservirs, lcaed ducing and penings acuaed by smke deecrs. ynamic smke exracin sysem in residenial buildings will be fcused in is paper.. REQUIREMENTS ON FORE VENTILTION SYSTEM IN HIN FIRE OES Requiremens f frced venilain design fr buildings in ina are specified by fur cdes f pracices: de fr fire precin design f indusrial building, sres and general aparmens (GJ- 6-87, 995)[5] de fr fire precin design f all buildings (G545-95, 997)[6] de fr fire precin design f cmmercial buildings (JGJ48-88, 989) [7] de fr fire precin design f garage, mr-repair-sp and parking-area (G567-97, 998) [8] Were G cdes are nainal sandards. GJ cdes are nainal sandards fr cnsrucin. JJ cdes are sandards fr cnsrucin and civil engineering. Fllwing e building cdes [5-8], frced venilain sysem and smke exrac sysem suld be insalled in e fllwing buildings, bearing in mind a buildings are classified in G545-95, 997 [6] as in Table : Tall buildings f ype I and ype II (see Table ) ver m ig wi venilain r crridrs ver 6 m, basemen ver m in al r eac single rm ver 5 m, aria f m ig and basemen, refuge level; Undergrund carparks ver m ; Subways, individual deparmen sres, spials and mels wi usable area exceeding 5 m ; Resaurans, exibiin ceners, gymnasiums, ball alls, skaing ranks wi usable area exceeding m and decraed by nncmbusible maerials. Or, e usable area exceeds 5 m and decraed by cmbusible maerials; inemas and audiriums; 8

3 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Libraries, canceries and wrksps wi usable area exceeding m ; Undergrund buildings wi smke-prf saircases insalled. Minimum requiremens f frced venilain fr residenial buildings in e ina cde are swn in Table. Specificain under e lcal cdes [9- ] are swn as well. Requiremens n e air cange raes are similar excep ere is large difference in indusrial buildings. Te exracin rae f 5 air canges per ur (H) in e ina cde is muc larger an a f 8 H in e Hng Kng cde. pssible explanain is because ms indusrial buildings in Mainland ina are fr eavy indusry. Terefre, iger air cange rae is required mainain e air qualiy inside e facry. Te requiremens fr smke exracin sysem in e ina fire cdes are [6,,]: Smke exracin rae is 4 8 H in general, ver 5 H fr indusries, wi minimum smke exrac sizing based n 7 m, 6 m r - fr eac smke-prf zne. Smke exracin rae is 6 H fr aria less an 7 m, r 4 H fr aria larger an 7 m. Minimum make up air rae is 5% 8% f e exracin rae in general. Requiremens n smke deecin sysem can be referred Te uilding Sandard Law f Japan [] and riis Sandard 589 []. Smke spreading is limied by cmparmenains r smke barriers. Te requiremens n frced venilain design is cnsidered. Te riznal velciy f smke spreading is..8 ms -, and e verical velciy f smke spreading is 4 ms - []. Referring e requiremens in Japanese building law [,], smke exracin rae suld be 4 m s - r 44 m r -. Wind speed a e inle suld be less an 7 ms - and wind speed a e ule suld be less an ms - []. In Hng Kng fire cdes, e requiremens fr wind speed a e ule suld be less an 6 ms - [9]. Table : lassificain f buildings lised in de fr fire precin design f all buildings (G545-95, 997) lassificain Type I Type II Residenial buildings Public buildings Hig-grade residence, cmmn residence wi mre an 9 flrs Hspials, mels, bradcasing and TV sain buildings, ps-ffice building, libraries, impran ffice buildings, cmmercial buildings and muliple use buildings ver 5 m ig r ver 5 m in eac flr area. mmn residence wi 8 flrs uildings excep lised in Type I Table : cmparisn f minimum frced venilain requiremens fr residenial buildings in Hng Kng cde [9-] and ina cde [5-8] uilding uses Minimum exracin rae ina Mainland de Hng Kng de Hel 4-6 H H Indusrial 5- H 8 H buildings asemen 8 H 6 m r - fr eac 8 H smke prf zne mmercial 8.5 m r - per persn 8 H buildings ria 4-6 H 8 H arparks H = air canges per ur 6 H 8 H 9

4 Inernainal Jurnal n Engineering Perfrmance-ased Fire des 4. SE STUIES Tw cases are cnsidered fr illusraing e frced venilain requiremens applied in differen ypes f buildings under ina fire cdes: ase : undergrund carpark m undergrund carpark wi smke exracin rae f 6 H as required in de fr fire precin design f garage, aumbiles wrksps and parking-area (G567-97, 998) [8]. Te building eig is 4 m, and ere is a dr pening f 6 m 4 m. ase : single rm 5 m single rm wi smke exracin rae f 8 H as required in de fr fire precin design f all buildings (G545-95, 997) [6]. Te rm eig is m, and ere is a dr pening f m m. m by m fire is lcaed a e cener wi ea release rae fllwing a NFP -fire [] wi cuff value f 5 MW. ll e fur ses f slw, medium, fas, and ulra-fas -fires are esed wi e fire zne mdel in FIREWIN [4] aken as e simulain l. In suc a zne mdel, a ermal plume is induced by e fire and a sable ermal sraified upper layer is frmed. Tis gives w znes in b e carpark and e single rm: an upper zne and a lwer cl zne. Wen e fire sared, e dr is su dwn immediaely. Te smke exracin sysem is expeced perae a w differen imes p :.45 is e ime wen e smke layer ickness is.45 m, crrespnding a ypical dwnsand eig in e ina fire cde [6] and e Hng Kng building fire cde [6]. 68 is e ime wen e smke layer emperaure is eaed up 68 a ceiling. Tis is a cmmn acuain emperaure fr sprinkler ead. Ne a a 68 -raed sprinkler ead mig n be acuaed wen e smke layer emperaure reaces 68, depending n is respnse ime index. Fas respnse ype sprinkler ead is assumed in is analysis s a e sprinkler ead wuld be acivaed nce e emperaure reaces 68. Tis pin is very impran as e smke exracin sysem mig be peraed firs befre a slwer respnse ype sprinkler ead, if b sysems are insalled. Te iniial emperaure is aken be. Flasver in e enclsure is assumed ccur wen e upper layer gas emperaure reaces 5 as lised in e User s Manual f FIREWIN [4]. Fry cases were simulaed. 5. RESULTS Time perae e smke exracin sysem in e carpark and in e single rm are swn in Table 4. Typical resuls f e smke layer emperaure T s (in ) and smke layer inerface eig (in m) wi e exracin sysem peraed a e w perain imes in e carpark are swn in Figs. 4. Resuls fr e single rm are swn in Figs Te ime perae e exracin sysem is impran. Fr a slw fire in e carpark, smke exracin sysem was peraed wen e smke layer ickness was.45 m. s was needed afer e fire ad sared make e exracin sysem perae, and aner 76 s fr e smke layer emperaure reac 68 acivae e sprinkler. uring is perid, e smke exracin sysem culd keep e smke layer a beween.5.5 m ig, wic gave enug ime and very safe envirnmens fr e evacuain f uman and veicles. fer a, e smke layer fell belw.5 m. Fr a slw- fire in e single rm, weer e dr is clsed r n as lile effecs n e ime perae e smke exracin sysem. 4 s was needed afer e fire ad sared make e exracin sysem perae, and aner 48 s fr e smke layer emperaure reac 68 acivae e sprinkler. Flasver ccurred a 7 s afer e fire ad sared in e case f smke exracin sysem peraed a.45. Frm e ime e fire ad been deeced e perain f sprinkler, ccupans wuld ave 48 s (nearly.5 mins) fr evacuain, wile e smke layer eig was kep a iger an.6 m. I is als bserved a requiremens f smke exracin sysem fr carpark are effecive, e smke layer can be kep a a iger psiin. u small exracin raes wuld n ave any effec in e small single rm. Te same resuls are fund in all e fur ses f slw, medium, fas, and ulra-fas -fires.

5 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Table 4: Time perae e smke exracin sysem in e carpark and single rm NFP -fires ar park r clsed Single rm r pen p a.45 p a 68 p a.45 p a 68 p a.45 p a 68 Slw s 84 s 4 s 6 s 4 s 6 s Medium 4 s 45 s 6 s 6 s 8 s 7 s Fas 56 s 65 s 8 s 5 s s 5 s Ulra-fas s 77 s 6 s 5 s 7 s 7 s 4 Smke layer inerface eig / m ime / s 4 Smke layer emperaure T / Smke emperaure emperaure ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 Fig. : Smke layer inerface eig and emperaure in e carpark under an NFP slw -fire

6 Inernainal Jurnal n Engineering Perfrmance-ased Fire des I is bserved a e smke layer wuld fall lw level quickly in e single rm. Even if e exracin sysem was peraed a an earlier ime, e smke layer culd n be kep a iger psiins. Terefre, i can be cncluded frm e simulaed resuls a e exracin sysem as n effec n e fire envirnmen in e small single rm, apar frm reducing e emperaure sligly, say by %. N flasver ccurred in e carpark simulain. Resuls n e ime flasver f in e single rm fr e w peraing imes p f e smke exracin sysem under a slw, medium, fas, and ulra-fas -fire are swn in Table 5. I is bserved a ime flasver f wuld be lnger wen e smke exracin rae was increased. Smke layer inerface eig / m ime / s Smke layer emperaure T / emperaure ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 Fig. : Smke layer inerface eig and emperaure in e carpark under an NFP medium -fire

7 Inernainal Jurnal n Engineering Perfrmance-ased Fire des 4 Smke layer inerface eig / m. 5. 5, ime / s 4 Smke layer emperaure T / emperaure ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 Fig. : Smke layer inerface eig and emperaure in e carpark under an NFP fas -fire Table 5: Time flasver in e single rm NFP -fires Naural venilain r clsed Sysem peraed p a.45 and 68 Sysem peraed wi dr pen Slw 6 s 96 s 7 s 54 s Medium 57 s 479 s 55 s 58 s Fas 88 s 55 s 58 s 9 s Ulra-fas 78 s 6 s 6 s 8 s

8 Inernainal Jurnal n Engineering Perfrmance-ased Fire des 4 Smke layer inerface eig / m ime / s 4 Smke layer emperaure T / emperaure ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 Fig. 4: Smke layer inerface eig and emperaure in e carpark under an NFP ulra-fas -fire 6. ONLUSION Frced-venilain requiremens in e ina fire cdes are reviewed wi se relaed venilain cnrl insallain briefly ulined. Te air canges per ur r fan exracin rae in b e ina fire cdes and e Hng Kng fire cdes are cmpared. Tw cases n an undergrund carpark and a single rm in a all building were used fr illusraing e ina fire cdes. Resuls swed a e frced-venilain requiremens in e ina fire cdes are reasnable and wuld saisfy e fire safey bjecives n life safey and prperies precin. Fllwing e requiremens wuld give sufficien evacuain ime inside e building. Fire figers can en ake apprpriae acin. 4

9 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Smke layer inerface eig / m. 5 F E ime / s ' ' Smke layer emperaure T / emperaure F E ' ' 5 5 ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 E Smke exracin sysem peraed a smke layer ickness f.45 m wi dr pen F Smke exracin sysem peraed a smke layer emperaure f 68 wi dr pen Fig. 5: Smke layer inerface eig and emperaure in e single rm under an NFP slw -fire 5

10 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Smke layer inerface eig / m. 5 F E ime / s ' ' Smke layer emperaure T / emperaure E F ' ' ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 E Smke exracin sysem peraed a smke layer ickness f.45 m wi dr pen F Smke exracin sysem peraed a smke layer emperaure f 68 wi dr pen Fig. 6: Smke layer inerface eig and emperaure in e single rm under an NFP medium -fire 6

11 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Smke layer inerface eig / m. 5 F E ime / s ' ' Smke layer emperaure T / emperaure E F ' ' ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 E Smke exracin sysem peraed a smke layer ickness f.45 m wi dr pen F Smke exracin sysem peraed a smke layer emperaure f 68 wi dr pen Fig. 7: Smke layer inerface eig and emperaure in e single rm under an NFP fas -fire 7

12 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Smke layer inerface eig / m F E ime / s ' ' Smke layer emperaure T / emperaure E F ' ' ime / s Naural venilain N venilain Smke exracin sysem peraed a smke layer ickness f.45 m Smke exracin sysem peraed a smke layer emperaure f 68 E Smke exracin sysem peraed a smke layer ickness f.45 m wi dr pen F Smke exracin sysem peraed a smke layer emperaure f 68 wi dr pen Fig. 8: Smke layer inerface eig and emperaure in e single rm under an NFP ulra-fas -fire REFERENES. NFP 9, Recmmended pracice fr smke cnrl sysem, Nainal Fire Precin ssciain, Quincy, M, US ().. NFP 9, Guide fr smke managemen sysems in malls, aria and large areas, Nainal Fire Precin ssciain, Quincy, M, US ().. lause explanain f design cde fr residenial buildings (G545-95), Minisry f nsrucin, P.R. ina (995). 4. esign cde fr residenial buildings (G ), Minisry f nsrucin, P.R. ina (999). 5. de fr fire precin design f indusrial building, sres and general aparmens (GJ-6-87, 995), Minisry f Public Securiy, Minisry f nsrucin, P.R. ina (995). 6. de fr fire precin design f all buildings (G545-95, 997), Minisry f Public Securiy, Minisry f nsrucin, P.R. ina (997). 7. de fr fire precin design f cmmercial buildings (JGJ48-88, 989), Minisry f Public 8

13 Inernainal Jurnal n Engineering Perfrmance-ased Fire des Securiy, Minisry f nsrucin, P.R. ina (989). 8. de fr fire precin design f garage, mrrepair-sp and parking-area (G567-97, 998), Minisry f Public Securiy, Minisry f nsrucin, P.R. ina (998). 9. aper uildings Ordinance, Laws f Hng Kng, uildings eparmen, Hng Kng (997).. Pracice f design and cmmissining f e smke cnrl sysems fr Hng Kng, Fire Services eparmen, Hng Kng (994).. des f Pracice fr Minimum Fire Service Insallains and Equipmen and Inspecin and Tesing f Insallains and Equipmen, Fire Services eparmen, Hng Kng (994).. Minisry f nsrucin f Japan, Te uilding Sandard Law f Japan/ ugus 994, Te uilding ener f Japan, Tky.. riis Sandard 589, S 589 Par 6, de f pracice fr e design and insallain f fire deecin and alarm sysems in dwellings, riis Sandards Insiuin, Lndn, UK (995). 4. FIREWIN user s manual versin., Fire mdelling & cmpuing (FM), 66 Wesbrk venue, Warnga, N.S.W. 74, usralia (997). 5. de f Pracice fr e Prvisin f Means f Escape in ase f Fire, uildings eparmen, Hng Kng (996). 6. de f Pracice fr Fire Resising nsrucin, uildings eparmen, Hng Kng (996). 9