[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-111-1-fire-science-016":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-016","fire-111-1-fire-science-016",111,1,16,"比較積污導電與金原現象之差異，下列何者錯誤？",{"A":16,"B":17,"C":18,"D":19},"因電解質等物質附著而通電者，為積污導電現象","積污導電又稱電痕","金原現象又稱為沿面洩漏放電","金原現象為有機絕緣體石墨化","C",null,[],false,"本題考點：電氣火災中兩種絕緣劣化現象——積污導電（電痕）與金原現象（石墨化）的辨異。\n【正解理由】積污導電是絕緣體表面附著含電解質的塵埃、鹽分或濕氣後，於施加電壓時沿表面產生洩漏電流，反覆的沿面洩漏放電使表面有機物碳化，形成樹枝狀導電痕跡即電痕（tracking），最終短路發熱起火。金原現象則是有機絕緣體長期承受微小火花或局部放電，逐漸碳化生成石墨質導電層，故又稱石墨化現象，其導電路徑形成於材料本體而非表面污染。「沿面洩漏放電」是積污導電的特徵，選項將其冠給金原現象，屬張冠李戴，故選 C。\n【逐項排除】\n(A) 積污導電的成因即為電解質、鹽分、金屬粉等附著於絕緣表面而使其通電，敘述正確。\n(B) 積污導電因會在絕緣表面留下碳化的導電痕跡，故又稱電痕現象，敘述正確。\n(C) 沿面洩漏放電為積污導電的機制，金原現象的別稱應為石墨化現象，敘述錯誤，為本題應選者。\n(D) 金原現象的本質即有機絕緣體受微小放電作用後石墨化而具導電性，敘述正確。\n【記憶點】表面髒污走沿面的是積污導電（電痕），材料本體碳化成石墨的才是金原現象。","電氣火災的成因體系可分為短路、過負載、接觸不良（含半斷線）、漏電、絕緣劣化，以及本題的積污導電與金原現象。後兩者之所以常被並列命題，是因為兩者的結果都是「原本絕緣的材料變成會導電並發熱」，但路徑完全不同，正是命題者製造混淆的著力點。\n積污導電的成立需要四個條件同時具備：絕緣表面、附著的電解質（塵埃、鹽分、飲料殘漬）、水分或濕氣，以及持續施加的電位差。四者齊備後，表面形成微弱洩漏電流，電流集中處局部乾燥而產生小電弧，電弧把表面有機物碳化，碳化痕又成為新的導電路徑，如此正回饋反覆進行，痕跡愈長愈粗，最後兩極間貫通造成短路。它最典型的發生位置是插頭與插座之間長期未拔除、積塵受潮的縫隙，火災調查上會在絕緣座表面看到樹枝狀或蜿蜒的黑色碳化軌跡。\n金原現象則不需要表面污染。有機絕緣體（酚醛樹脂、聚氯乙烯、木材等）長期承受微小火花、局部放電或高溫，內部有機成分裂解、揮發分逸出，殘留的碳逐漸重組為具導電性的石墨質結構，材料電阻隨之緩慢下降，最終在無明顯外部異常的情況下發熱起火。它的過程可長達數月甚至數年，屬於典型的「潛伏型」電氣火災原因。\n辨識上可掌握三個關鍵字：積污導電看「表面、污染、沿面放電、電痕」，金原現象看「本體、碳化、石墨化、潛伏」。兩者的共通點也值得整理：起火前都經歷絕緣電阻由高變低的漸進過程，都不需要負載電流過大，因此過電流保護裝置不會動作，火災往往在無人察覺的狀態下發生，這正是它們在電氣火災統計中占有一席之地的原因。延伸考點包括電氣火災調查中一次熔痕與二次熔痕的判別、漏電火災須具備漏電點、出火點與接地點三要素，以及絕緣電阻測定值在火災原因鑑定上的意義。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-111-1-fire-science-015","下列發火源在理化現象歸類上，何者與其他不同類別？",15,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-111-1-fire-science-017","有關閃燃（Flashover）與複燃（Backdraft）的敘述，何者錯誤？",17,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-111-1-fire-science-014","普通木造建築物旁欲蓋 9 公尺高之建築物，其延燒係數為 3 級（係數為 0.15），其防火間隔應保持多少公尺？",14,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-111-1-fire-science-018","下列何者非電線走火之原因？",18,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-111-1-fire-science-013","高層建築物火災特性下列何者錯誤？",13,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-111-1-fire-science-019","有關火羽流及天花板噴射流的敘述，下列何者錯誤？",19,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-110-1-fire-science-016",110,"市面上販售的 ABC 乾粉滅火器內充填的乾粉滅火藥劑主要成分為：",{"webId":58,"year":59,"stem":60,"number":13},"fire-109-1-fire-science-016",109,"假設建築物外部風速為 10 m\u002Fs，風壓係數為 0.6，空氣密度為 1.0 kg\u002Fm3，其對迎風面建築物所產生的風壓約為？",{"webId":62,"year":63,"stem":64,"number":13},"fire-108-1-fire-science-016",108,"某發生火警的大樓，室內外溫度分別為 800℃與 20℃，中性帶位於 4 樓；6 樓的內外壓差為 60 Pa，若不考慮外部風等其他因素，則 8 樓的內外壓差約為若干 Pa？",{"webId":66,"year":67,"stem":68,"number":13},"fire-107-1-fire-science-016",107,"下列何者為海龍替代品滅火藥劑 FE-13 之分子式？",{"webId":70,"year":71,"stem":72,"number":13},"fire-106-1-fire-science-016",106,"下列有關粉塵爆炸之敘述，何者錯誤？",1785123161963]