Rangarira ndima iri pasi apa uye ipapo pindura mubvunzo gare gare mumutauro mumwe chetewo sechikamu:  Passage: U.S. National Institute of Standards and Technology (NIST) yakaongorora kupunzika kweTwin Towers neWTC 7. Ongororo dzacho dzakatsvakurudza kuti nei zvivako zvacho zvakabhururuka uye kuti zvii zvaiitwa pakudzivirira moto, uye zvakaongororwa kuti nzira dzokudzivirira moto dzingavandudzwa sei pakuvaka mune ramangwana. Kuongororwa kwokuputsika kweWTC 1 neWTC 2 kwakapedzwa muna October 2005 uye kweWTC 7 kwakapedzwa muna August 2008. NIST yakawana kuti fireproofing pamusoro peTwin Towers' steel infrastructures yakaparadzwa nekuputika kwokutanga kwendege uye kuti, kudai izvi zvisina kuitika, shongwe dzaizodai dzakaramba dzakamira. Kudzidza kwakaitwa muna 2007 kwokuputsika kwechivako chokuchamhembe kwakabudiswa nevatsvakurudzi vePurdue University kwakaratidza kuti, sezvo kurovera kwendege kwakanga kwabvisa chikamu chikuru chechinhu chinodzivirira kupisa chechivako, kupisa kunobva pamoto womuhofisi kunofanira kunge kwakanyorova uye kwakaderedza matanda akafukidzwa uye mbiru zvakakwana kutanga kuputsika zvisinei nenhamba yemakoramu akachekwa kana kukuvadzwa nekurovera. Mutungamiriri weongororo yepakutanga akataura kuti "shongwe dzakaita zvinoshamisa chaizvo. Ndege dzamagandanga hadzina kuparadza zvivako; moto ndiwo wakatevera. Kwakanga kwaratidzirwa kuti iwe unogona kubvisa zvikamu zviviri muzvitatu zvezvitubu zviri mushongwe uye chivako chaizoramba chakamira". Moto wacho wakaderedza masimbi anotsigira pasi, zvichiita kuti pasi risendame. Pasi rakatsvedza rakakweva mbiru dzesimbi dzokunze dzichiita kuti mbiru dzokunze dzikombamire mukati. Sezvo mbiru dzomukati dzakanga dzaparadzwa, mbiru dzokunze dzakanga dzisingachakwanisi kutsigira zvivako, zvichiita kuti zviparare. Mukuwedzera, mushumo wacho wakawana kuti masitepisi enharire akanga asina kusimbiswa zvakakwana kugovera kutiza kwokukurumidzira kwakakwana nokuda kwavanhu vari pamusoro penzvimbo dzokubonderana. NIST yakagumisa kuti moto usina kudzorwa muWTC 7 wakaparira kuti matanda epasi namatanda okunze apise uye gare gare "wakaparira kuti mbiru inokosha yokutsigira ikundikane, ichitanga kuputsika kunopfuurira kunokonzerwa nomoto uko kwakaunza chivako pasi".  Mubvunzo: Chii chakanga chisina kusimbiswa zvakakwana mumasvingo?
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