[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-112-1-fire-science-036":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-112-1-火災學概要-036","fire-112-1-fire-science-036",112,1,36,"下列那一種措施有助於提高粉塵爆炸的防護作用以增加其安全性？",{"A":16,"B":17,"C":18,"D":19},"提高粉塵濃度","提高環境溫度","提高環境濕度","提高環境壓力","C",null,[],false,"本題考點：粉塵爆炸的防護對策，判斷哪一項環境條件的改變會降低爆炸危險。\n【正解理由】依粉塵爆炸的成立要件（可燃性粉塵、懸浮成雲並達適當濃度、氧氣、點火源、相對密閉空間），提高環境濕度可使粉體吸附水分而增強顆粒間的凝聚力，不易揚起與維持懸浮；水膜同時提高表面導電度，把輸送與傾倒過程累積的靜電荷洩放掉，減少靜電放電這個最典型的點火源；水分汽化吸熱亦不利火焰傳播，故選 C。\n【逐項排除】\n(A) 提高粉塵濃度使粉塵雲更接近或落入爆炸範圍，是增加危險而非防護。\n(B) 提高環境溫度會降低最小起火能量並使爆炸範圍變寬，危險性上升。\n(C) 正確：增濕同時抑制揚塵、消除靜電並吸收熱量，是粉體處理場所常見的防爆方向。\n(D) 提高環境壓力使單位體積內的可燃物與氧分子增多，爆炸上限與爆炸壓力隨之提高，火焰傳播亦同步加快，危險性上升。\n【記憶點】粉塵防爆記「增濕、除塵、消靜電」，濃度、溫度、壓力三項升高都把系統推向危險側，只有濕度往安全方向走。","粉塵爆炸的防護思路分兩條：一是不讓可燃粉塵雲形成，二是不讓點火源出現。提高相對濕度同時作用在這兩條路徑上。水分被粉體表面吸附後，顆粒間形成液橋，凝聚力增強，粉體傾向團聚沉降而難以維持懸浮狀態，可燃粉塵雲的濃度不易進入爆炸範圍；同時粉體在輸送、篩分、傾倒時因摩擦與分離而累積的靜電荷，可藉吸附水膜提高表面導電度而洩放，減少靜電放電。此外水分汽化需吸收潛熱，會削弱顆粒受熱裂解與火焰傳播的能力。\n環境條件對爆炸危險性的影響有一組通則可整批記憶：溫度上升，最小起火能量下降、爆炸下限下降、爆炸範圍變寬；壓力上升，單位體積內可燃物與氧的分子數增加，爆炸上限明顯提高，爆炸壓力與壓力上升速率隨之增大；濃度則須落在爆炸下限與上限之間才會爆炸，提高粉塵濃度只是把系統推向或推進爆炸範圍。\n其他常見的粉塵爆炸防護手段包括惰性化，即以氮氣等惰性氣體把氧濃度降到極限氧濃度以下；除塵與清掃以消除沉積粉塵，避免二次爆炸的燃料來源；接地與等電位連結以消除靜電；設置爆炸洩放口或抑制系統以限制爆炸壓力；以隔離裝置阻斷爆炸沿管路傳播。\n易混淆之處在於：增濕對粉塵爆炸有效，對可燃性氣體的爆炸抑制效果則相當有限，因為氣體不需懸浮，其點火機制也不以靜電為主。另須注意增濕主要作用在「粉塵雲不易形成」這一段，對於已經揚起且達爆炸範圍的粉塵雲，抑制效果就有限，因此除塵與清掃在防護順序上同樣關鍵。延伸考點包括極限氧濃度的定義、金屬粉塵遇水產生氫氣的風險，以及粉塵爆炸五要素與氣體爆炸三要素的辨識。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-112-1-fire-science-035","相較於氣體爆炸，一般的粉塵爆炸具有下列那種性質？",35,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-112-1-fire-science-037","升高環境溫度對於環氧乙烷的分解爆炸有何影響？",37,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-112-1-fire-science-034","對於具有分解爆炸性質的可燃性氣體，下列敘述何者錯誤？",34,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-112-1-fire-science-038","當外部風的風向不變而風速加倍時，對處於煙囪效應下的大樓而言，下列敘述何者正確？",38,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-112-1-fire-science-033","當防火門兩側的壓力差加倍時，其透過門縫所流出的氣體體積流率有何變化？",33,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-112-1-fire-science-039","假設定量乙醇(C2H5OH)與理論空氣量混合後產生完全燃燒，其後將燃燒廢氣冷卻至常溫，則其中二氧化碳的濃度約為多少%？",39,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-113-1-fire-science-036",113,"依美國防火協會（NFPA）危險物品標示規定，黃色代表何種危險性？",{"webId":58,"year":59,"stem":60,"number":13},"fire-111-1-fire-science-036",111,"下列有關燃燒速度之敘述，何者錯誤？",{"webId":62,"year":63,"stem":64,"number":13},"fire-110-1-fire-science-036",110,"為防止靜電發生放電時引火造成火災，請問下列有關靜電災害之防止對策何者錯誤？",{"webId":66,"year":67,"stem":68,"number":13},"fire-109-1-fire-science-036",109,"房間的體積為 V=6 m×5 m×3 m，其中 O2 占 0.21 V，請問至少要加入多少公升（L）的 CO2 讓燃燒作用無法持續？",{"webId":70,"year":71,"stem":72,"number":13},"fire-108-1-fire-science-036",108,"下列何者不是 IG-541 氣體滅火藥劑的成分？",1785129966629]