[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-111-1-fire-science-007":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-111-1-火災學概要-007","fire-111-1-fire-science-007",111,1,7,"油類火災為何種火災？",{"A":16,"B":17,"C":18,"D":19},"A 類火災","B 類火災","C 類火災","金屬火災","B",null,[],false,"本題考點：火災分類的判別基準，以及油類火災所屬類別。\n【正解理由】火災依燃燒物性質分類，目的在對應有效的滅火手段。汽油、柴油、燈油、動植物油脂、油漆等可燃性液體及油脂類所引起的火災，定義上歸為 B 類火災，其滅火主軸是窒息與抑制燃燒連鎖反應，而非以水冷卻。題目所問的油類火災即屬此類，故選 B。\n【逐項排除】\n(A) 錯誤。A 類為普通火災，指木材、紙張、纖維、棉毛、塑膠、橡膠等一般可燃固體，燃燒後留下灰燼，以冷卻為主要滅火手段。\n(B) 正確。B 類即油類火災，涵蓋可燃性液體與可燃性固體油脂，燃燒發生在液面上方的蒸氣層。\n(C) 錯誤。C 類為電氣火災，指通電中的變壓器、配電盤、電動機等電氣設備起火，重點在滅火藥劑須不導電。\n(D) 錯誤。金屬火災為 D 類，指鈉、鉀、鎂、鋁粉等活性金屬燃燒，遇水會生成氫氣而加劇，須以專用乾粉或乾砂覆蓋。\n【記憶點】A 灰、B 油、C 電、D 金屬；對應冷卻、窒息、絕緣、覆蓋。","火災分類把「燃燒物特性」與「有效滅火手段」綁在一起，是滅火器適用標示的根據。A 類普通火災的可燃物為木材、紙張、纖維、塑膠等，燃燒屬表面燃燒與分解燃燒併存、且會殘留灰燼，深層蓄熱需要滲透與冷卻，故以水最有效。B 類油類火災的燃燒實際發生在液面上方蒸氣層，液體本身並不直接燃燒，故切斷蒸氣與空氣的接觸最有效，泡沫覆蓋、二氧化碳窒息、乾粉抑制連鎖反應都屬此理。C 類電氣火災的關鍵不在燃燒物，而在「是否通電」，因藥劑導電會使操作者觸電，故採二氧化碳或乾粉。D 類金屬火災的活性金屬遇水會置換出氫氣、遇二氧化碳亦會還原反應，只能以專用金屬火災乾粉或乾砂覆蓋隔絕。\n記憶口訣可用「A 灰、B 油、C 電、D 金屬」，再配上「A 冷卻、B 窒息、C 絕緣、D 覆蓋」。另有源自美國分類的 K 類烹調油脂火災，台灣多歸入 B 類處理，其特色是自燃溫度高、油槽蓄熱深，撲滅後容易復燃，強調以皂化作用形成皂膜隔絕，屬延伸命題點。\n油類火災的特殊性也是常考焦點：油品比重多小於水且不溶於水，若以棒狀水柱射入，水會沉入油下受熱汽化並將油品噴濺出來，反而擴大火面。大型儲槽火災更有沸溢（boil over）、濺溢（slop over）、冒溢（froth over）三種現象，分別對應熱波下移使槽底水層汽化、水霧接觸高溫油面、以及含水油品注入高溫槽內，三者的成因與後果是申論與測驗題的固定素材。\n易混淆對照：判斷 B 類看燃燒物是否為油品，判斷 C 類看是否通電；通電中的電氣設備起火為 C 類，一旦斷電後燃燒的若是絕緣材料與外殼，即回歸 A 類，這個「以是否通電為界」的判準是選擇題最常見的陷阱。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-111-1-fire-science-006","火災成長歷程中，下列何者非閃燃之現象？",6,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-111-1-fire-science-008","空氣氧之重量占整體之 23%，故 1 公斤碳完全燃燒需要多少空氣？",8,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-111-1-fire-science-005","在苯中置入油酸鎂等金屬鹼，係採取下列何種防止靜電發生的方法？",5,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-111-1-fire-science-009","有關粉塵爆炸的敘述，下列何者錯誤？",9,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-111-1-fire-science-004","日本東京放映所及精神病診所火災起因為縱火，請問汽油在空氣中的燃燒下限為何？",4,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-111-1-fire-science-010","火場當中煙毒危害，下列敘述何者錯誤？",10,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-114-1-fire-science-007",114,"油類火災沸溢（Boilover）與濺溢（Spilover）現象之發生區別，下列何者錯誤？",{"webId":58,"year":59,"stem":60,"number":13},"fire-113-1-fire-science-007",113,"依公共危險物品及可燃性高壓氣體製造儲存處理場所設置標準暨安全管理辦法，第四類公共危險物品對於易燃液體定義，是指在一大氣壓時，閃火點在攝氏幾度以下之液體？",{"webId":62,"year":63,"stem":64,"number":13},"fire-112-1-fire-science-007",112,"高壓氣體之爆炸界限，通常較常壓下為廣，下列何者氣體之爆炸界限，會呈現加壓時上、下限初呈狹窄，但繼續加壓後又變廣的現象？",{"webId":66,"year":67,"stem":68,"number":13},"fire-110-1-fire-science-007",110,"己烷在閃火點時的飽和蒸氣壓為 9.12 mmHg，根據 Burgess-Wheeler 定理其燃燒熱約為多少 kcal\u002Fmole？",{"webId":70,"year":71,"stem":72,"number":13},"fire-109-1-fire-science-007",109,"進入石化工廠，車輛會被要求在排氣管加裝滅焰器（flame arrester）以避免火災爆炸之發生，加裝該措施防制火災爆炸之原理為：",1785129966726]