[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-108-1-fire-science-035":3},{"subject":4,"subjectSlug":5,"subjectKicker":6,"subjectShort":7,"question":8,"related":27,"sameNumber":52,"hasEssay":26},"火災學概要","fire-science","火災學 · Fire Science","火災學",{"id":9,"webId":10,"year":11,"session":12,"subject":4,"number":13,"stem":14,"options":15,"answer":20,"answerNote":21,"images":22,"imagesPending":23,"lawTimestamp":11,"explanation":24,"explanationDeep":25,"freq":12,"indexable":26},"fire-108-1-火災學概要-035","fire-108-1-fire-science-035",108,1,35,"為避免液化石油氣儲槽因外圍起火燃燒，一時無法撲滅而發生 BLEVE 現象，可採取之防救策略下列何者正確？",{"A":16,"B":17,"C":18,"D":19},"槽體附近設置固定式撒水設備降低儲槽溫度","設置防液堤將洩漏之燃料限制於槽體周圍","降低安全閥的壓力設定值，使內壓上升速度增加","減低槽體絕緣層，以避免熱蓄積","A",null,[],false,"本題考點：液化石油氣儲槽在外圍火災下發生沸騰液體膨脹蒸氣爆炸(BLEVE)的機制,以及對應的防制策略。\n【正解理由】BLEVE 的成因是外部火焰持續加熱槽體,液面以上的氣相部因內側無液體帶走熱量,鋼板溫度急速升高、抗拉強度下降,同時槽內液體受熱汽化使內壓上升,當鋼板強度不足以承受內壓即破裂,槽內過熱液體瞬間閃蒸膨脹並形成火球。防制關鍵在「持續冷卻槽體、特別是氣相部外壁」,以固定式撒水設備在槽體形成水膜降溫最為直接有效,故選 A。\n【逐項排除】\n(A) 以固定式撒水設備冷卻槽體外壁,可抑制氣相部鋼板升溫、維持材料強度並減緩內壓上升,是防止 BLEVE 的正規作法,敘述正確。\n(B) 防液堤的功能是侷限洩漏液體、避免流竄擴大延燒面積,對槽體受熱本身無冷卻作用,液體滯留槽體周圍燃燒反而使受火更持續。\n(C) 安全閥的作用是及時洩壓以抑制內壓上升,敘述卻導向「使內壓上升速度增加」,與洩壓目的自相矛盾,顯屬錯誤。\n(D) 隔熱層是延緩外部熱量傳入槽體的重要屏障,減薄隔熱層只會加快液體受熱與鋼板升溫,反而促成 BLEVE。\n【記憶點】防 BLEVE 三件事:淋水降溫、隔熱保層、洩壓夠大。","BLEVE(Boiling Liquid Expanding Vapor Explosion,沸騰液體膨脹蒸氣爆炸)是加壓液化氣體容器在受火下的典型破壞型態,其發生條件可拆成三項:①容器內盛裝的液體溫度已高於常壓沸點,處於過熱狀態 ②容器因受熱、腐蝕或外力而突然失去完整性 ③壓力瞬間釋放使過熱液體大量閃蒸,體積膨脹數百倍。若內容物可燃,閃蒸後的蒸氣雲隨即被外圍火焰引燃而形成火球,輻射熱可波及數十至上百公尺,造成大範圍傷亡。\n\n特別要理解「為什麼破裂點在氣相部」:液相接觸的鋼板因液體沸騰帶走熱量,溫度受限於液體沸點附近;氣相部內側僅有蒸氣,熱傳係數低,鋼板溫度可在十餘分鐘內升至數百度,鋼材抗拉強度隨溫度上升而明顯衰減,於是先在液面上方鋼板產生鼓脹與撕裂。這也解釋了冷卻水為何要優先淋在液面以上的槽體外壁。\n\n防制策略可整理成四類:熱源阻絕(隔熱塗層、覆土或埋設)、冷卻(固定式撒水或水霧設備形成連續水膜)、洩壓(安全閥容量須足以排放受火時的蒸發量)、以及配置管制(槽體間距、防液堤導流至遠離槽體的收集區、遠距射水陣地)。要注意防液堤在此的角色是防止液體外流與導流,而非防止 BLEVE 本身。\n\n易混淆概念對照:BLEVE 屬物理性爆炸引發的後續燃燒現象;蒸氣雲爆炸(UVCE)是可燃氣體外洩後與空氣混合被引燃的化學性爆炸;噴射火焰(jet fire)則是加壓洩漏處的持續火炬。三者常在同一題組中出現,判別關鍵在於「容器是否破裂」與「爆炸能量來自相變或燃燒」。\n\n相關考點連結:液化石油氣儲槽受火後可能於數十分鐘內發生 BLEVE,故命題也常涉及火球直徑與輻射熱推估、安全距離設定,以及儲槽區固定式冷卻撒水設備的設置目的。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-108-1-fire-science-034","化學物質災害搶救程序 H.A.Z.M.A.T.中有關區域管制事項，下列敘述何者正確？",34,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-108-1-fire-science-036","下列何者不是 IG-541 氣體滅火藥劑的成分？",36,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-108-1-fire-science-033","電氣火災中，下列何者為積污導電現象？",33,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-108-1-fire-science-037","下列有關 GHS 制度之說明，何者錯誤？",37,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-108-1-fire-science-032","下列有關防止靜電災害的方法中，何者錯誤？",32,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-108-1-fire-science-038","可燃物不藉由火焰或電器火花引起燃燒，在大氣中僅因受熱而引發燃燒的最低溫度稱為：",38,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-111-1-fire-science-035",111,"下列何者為乾粉最主要滅火原理？",{"webId":58,"year":59,"stem":60,"number":13},"fire-110-1-fire-science-035",110,"面對廚房油鍋起火燃燒，下列何項應對動作的風險最大？",{"webId":62,"year":63,"stem":64,"number":13},"fire-109-1-fire-science-035",109,"有關引火性液體的敘述，下列何者正確？",{"webId":66,"year":67,"stem":68,"number":13},"fire-107-1-fire-science-035",107,"描述火勢大小之物理量為下列何者？",{"webId":70,"year":71,"stem":72,"number":13},"fire-106-1-fire-science-035",106,"五層樓的建築物，每層設有特別安全梯，樓梯採正壓且加壓壓力為 35 Pa，每層特別安全梯之前室採正壓且加壓壓力為 25 Pa，居室則未設煙控設計，居室避難到特別安全梯，需經過設有煙控之前室，且空間均為密閉構造，唯一開口為安全門，流動面積為 0.01 m2，試問每一排煙室設加壓煙控時，應送的風量為多少？",1785123163381]