版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請(qǐng)進(jìn)行舉報(bào)或認(rèn)領(lǐng)
文檔簡介
1、附錄一:中文譯文消防系統(tǒng)運(yùn)行可靠性的估計(jì)在過去的三年中,美國國家標(biāo)準(zhǔn)技術(shù)研究所(NIST)已經(jīng)在研究開發(fā)一種新的加密標(biāo)準(zhǔn),以確保政府的信息安全。該組織目前正處于為新的先進(jìn)加密標(biāo)準(zhǔn)(AES)選擇一個(gè)或幾個(gè)算法或數(shù)據(jù)打亂公式的開放過程的最后階段,并計(jì)劃在夏末或秋初作出決定。此標(biāo)準(zhǔn)內(nèi)定明年實(shí)施。Richard W. Bukowski:體育,高級(jí)工程師,瑟斯堡建筑及消防研究實(shí)驗(yàn)室的MST,美國醫(yī)學(xué)博士20899-8642;Edward K. Budnick:體育,巴爾的摩休斯聯(lián)合公司副總裁 ,美國醫(yī)學(xué)博士21227-1652;Christopher F. Scheme1,克里斯托弗計(jì)劃1,巴爾的摩休斯
2、聯(lián)合公司化學(xué)工程師、美國醫(yī)學(xué)博士21227-1652; 前言 背景資料:為執(zhí)行特定功能而設(shè)計(jì)和安裝的美國消防計(jì)劃。例如,自動(dòng)噴水滅火系統(tǒng)目的在于控制或撲滅火災(zāi)。為此: 自動(dòng)滅火系統(tǒng)必須長開,即能滿足火災(zāi)地所需水量達(dá)到控制或消滅火災(zāi),火災(zāi)探測(cè)系統(tǒng)是為了盡早提供火災(zāi)預(yù)警通報(bào)來通知樓內(nèi)人員安全逃生,并提供消防通知,使其他的消防組成部分開啟(例如,特殊滅火系統(tǒng)、排煙系統(tǒng))。兩種消防系統(tǒng)啟動(dòng)(檢測(cè))和(警報(bào))必須達(dá)到盡早報(bào)警。建筑防火墻的一般設(shè)計(jì)目的為:限制火災(zāi)蔓延的程度和保持建筑物的結(jié)構(gòu)的完整,以及在火災(zāi)發(fā)生時(shí)保護(hù)逃生路線的安全性。為了做到這一點(diǎn),特殊的消防系統(tǒng)必須按標(biāo)準(zhǔn)測(cè)試及保持特殊消防系統(tǒng)完整性的
3、特點(diǎn).。消防系統(tǒng)的組成部分如探測(cè)系統(tǒng)、自動(dòng)滅火系統(tǒng)、防火墻的可靠性,在于提高基于設(shè)計(jì)基礎(chǔ)上的聯(lián)合演習(xí)的細(xì)節(jié)分析的投入。在安全系統(tǒng)方面,有幾個(gè)可靠性要素包括有效和能使用的可靠性,運(yùn)行可靠性能提供一定程度的概率,即消防系統(tǒng)在需要時(shí)運(yùn)行。運(yùn)行可靠性能在特定的火災(zāi)情況下利用起特點(diǎn)成功完成起任務(wù)的一種檢測(cè)手段。前者是系統(tǒng)組成和可靠性的評(píng)估,而后者是系統(tǒng)設(shè)計(jì)適宜性的評(píng)估。這項(xiàng)研究的范圍僅限于運(yùn)行可靠性的評(píng)估,其主要原因是在于來自文獻(xiàn)資料內(nèi)容的可靠性。除了這項(xiàng)業(yè)務(wù)區(qū)分可靠性和性能,無條件評(píng)估的可靠性和故障估計(jì)的研究范圍也會(huì)在失控的火災(zāi)中列出。在該文件的后面將會(huì)提供這些條款的討論。 研究范圍:這份文件中提供了
4、關(guān)于(1)火災(zāi)探測(cè)(2)有限范圍內(nèi)的自動(dòng)滅火(3)防火墻的運(yùn)行可靠性和執(zhí)行可靠性的一些觀點(diǎn)。一般而言,火災(zāi)檢測(cè)的可靠性大都在于煙氣檢測(cè)或火災(zāi)報(bào)警系統(tǒng)。自動(dòng)噴頭構(gòu)成了大部分的自動(dòng)滅火的數(shù)據(jù),防火墻包括分區(qū)防火和圍墻的完整性。應(yīng)當(dāng)指出,在某些情況下,該文獻(xiàn)不會(huì)超出一般火災(zāi)探測(cè) 或自動(dòng)滅火的范疇和要求假設(shè)具體類型消防系統(tǒng). 幾項(xiàng)研究報(bào)告估計(jì)了火災(zāi)探測(cè)的可靠性和自動(dòng)滅火系統(tǒng)計(jì)劃。然而,對(duì)被動(dòng)防火系統(tǒng)如防火分區(qū)的詳細(xì)評(píng)估很少被發(fā)現(xiàn),如根據(jù)有限的統(tǒng)計(jì)資料經(jīng)分析后,被用來歸納包括評(píng)估和不確定的關(guān)聯(lián)性等信息。后者的作用僅限于文獻(xiàn)資料在檢測(cè)和滅火時(shí)的評(píng)估。防火分區(qū)的可靠性也包括與之關(guān)聯(lián)的不可靠數(shù)據(jù)。這份報(bào)告列出
5、了與放火系統(tǒng)相關(guān)的可靠性原理。為了回顧分析和重要發(fā)展以及數(shù)據(jù)概括,在文獻(xiàn)檢索時(shí)被完成。該文獻(xiàn)中適用于噴頭、煙霧偵測(cè)系統(tǒng)可靠性的數(shù)據(jù)已經(jīng)被分析篩選。這些數(shù)據(jù)是描述防火系統(tǒng)運(yùn)行可靠性在均值和95%的置信區(qū)間時(shí)的可靠性??煽啃苑治龅脑碓谖墨I(xiàn)中的數(shù)據(jù)可靠性和相關(guān)分析上有很大的變化?;旧?,可靠性是一種概率的估計(jì),即一個(gè)系統(tǒng)或其組成部分在一定時(shí)間內(nèi)按照設(shè)計(jì)正常運(yùn)行,其組成部分在正常運(yùn)行或預(yù)期壽命的時(shí)間中。這一時(shí)期是“改寫”的一個(gè)組成部分,是每次測(cè)試都發(fā)現(xiàn)是運(yùn)行正常的一個(gè)時(shí)。因此,系統(tǒng)及其組成部件越經(jīng)常測(cè)試和維修保養(yǎng),他們就越為可靠。這種形式的可靠性就叫做無條件。 系統(tǒng)正常運(yùn)行的可靠性是無條件的概率的估
6、計(jì)。有條件的可靠性是對(duì)所提及的兩件事情的估計(jì),即發(fā)生火災(zāi)和消防系統(tǒng)成功運(yùn)行在同一個(gè)時(shí)間內(nèi)發(fā)生??煽啃怨烙?jì)并不認(rèn)為火災(zāi)發(fā)生的幾率是無條件的估計(jì)。涉及到運(yùn)行可靠性的其他兩個(gè)重要概念是安全故障和危險(xiǎn)故障。無火災(zāi)發(fā)生時(shí),消防系統(tǒng)卻運(yùn)行叫做安全故障。一個(gè)常見的例子就是一個(gè)煙霧探測(cè)器的假報(bào)警現(xiàn)象。發(fā)生火災(zāi)時(shí)而消防系統(tǒng)卻不起作用,這叫做危險(xiǎn)故障。在這項(xiàng)研究中不能有效使用的概率(1-可靠性估計(jì))稱為危險(xiǎn)故障?;馂?zāi)期間自噴系統(tǒng)不能運(yùn)行或者運(yùn)行系統(tǒng)不能控制或撲滅火災(zāi)都是這種類型的失誤。整個(gè)系統(tǒng)的可靠性取決于各個(gè)組成部分的可靠性及其相應(yīng)的失敗率,系統(tǒng)組成部分的相互依存性,安裝后系統(tǒng)及其組成部分在維修和測(cè)試時(shí)所出拒的
7、評(píng)估。考慮到關(guān)鍵的可靠性時(shí)也涉及到消防系統(tǒng)的性能。系統(tǒng)性能被定義為某一特定系統(tǒng)的能力,為完成其設(shè)計(jì)安裝的任務(wù)。例如:被評(píng)估為性能分離的系統(tǒng),是基于在火災(zāi)期間各個(gè)組成部分在保持建筑物的構(gòu)造和防止火災(zāi)蔓延時(shí)的作用。系統(tǒng)性能根據(jù)其各個(gè)組件控制火災(zāi)蔓延的程度來界定。性能可靠性評(píng)估所需要的數(shù)據(jù)在于,消防系統(tǒng)在一般和大規(guī)?;馂?zāi)情況下完成設(shè)計(jì)目的的程度,性能可靠性的數(shù)據(jù)通過復(fù)檢這些數(shù)據(jù)的來源。因?yàn)檫@些作用取決于顯示數(shù)據(jù)的內(nèi)容,因此,這不是某單方面的作用。各種類型系統(tǒng)失敗的原因通常分為幾大類:安裝錯(cuò)誤,設(shè)計(jì)錯(cuò)誤,制造/設(shè)備缺陷,缺乏保養(yǎng),超過設(shè)計(jì)限額和環(huán)境因素,有幾種方法可以利用以減少失敗的概率,這些方法包括
8、:(1)冗余設(shè)計(jì),(2)積極監(jiān)測(cè)故障,(3)提供最簡單的系統(tǒng)(即最少的部件)為解決危險(xiǎn),以及(4)一個(gè)設(shè)計(jì)檢驗(yàn)、測(cè)試、維修計(jì)劃。這些運(yùn)行可靠性的概念都是重要的,當(dāng)運(yùn)行可靠性評(píng)估在溫憲忠報(bào)道時(shí),因?yàn)樵谀骋环治鲋杏玫降馁Y料,可靠性評(píng)估可能用到一個(gè)或多個(gè)上述概念,在這一范圍內(nèi)閱讀這一文獻(xiàn)時(shí)可酌情處理,大部分?jǐn)?shù)據(jù)是從支持這份論文的文獻(xiàn)中獲取得,這些文獻(xiàn)卻符合在無條件運(yùn)行可靠性!文獻(xiàn)檢索文獻(xiàn)檢索是搜集各種類型消防系統(tǒng)可能性的數(shù)據(jù),這些數(shù)據(jù)被認(rèn)為與安全計(jì)劃有關(guān):自動(dòng)滅火,自動(dòng)檢測(cè),和消防隔離。文獻(xiàn)檢索的目的是獲得特殊系統(tǒng)的運(yùn)行可靠性評(píng)估,這些特殊系統(tǒng)中每一種類型的消防系統(tǒng)都為一般的居住物(如住宅,商業(yè)建筑
9、和公用建筑)。信息來源包括全國火災(zāi)事故的數(shù)據(jù)資料,美國國防部安全記錄工業(yè)和住房的特殊研究,工業(yè)保險(xiǎn)歷史記錄和檢查報(bào)告的公開文獻(xiàn)和試驗(yàn)數(shù)據(jù)。試點(diǎn)工作和火災(zāi)測(cè)試結(jié)果的報(bào)告只有在火災(zāi)探測(cè)、自動(dòng)滅火或者防火隔離計(jì)劃時(shí)被明確評(píng)價(jià)是被利用,測(cè)試系統(tǒng)用于資格核準(zhǔn)或列表,并且用于審查失效方式的資料,英國公布的數(shù)據(jù)也包括日本、澳大利亞和新西蘭在內(nèi)。常識(shí)多個(gè)基礎(chǔ)廣泛的研究報(bào)告指出,這份調(diào)查是關(guān)于火災(zāi)探測(cè)和滅火系統(tǒng)還有防火分區(qū)的可靠性。這些包括(1)火災(zāi)研究1996托比在英國 (2)澳大利亞消防工程索引消防法改革中心、1996 (3)日本東京火災(zāi)統(tǒng)計(jì)匯編 東京消防處、1997 (四)日本研究消防系統(tǒng)根源的成果渡邊1
10、979。托比消防研究所致力于解決消防系統(tǒng)的可靠性和各組成部分的相互作用。德爾菲方法是一種用來揭示各個(gè)組成部分單獨(dú)使用時(shí)的可靠性估計(jì)。組成部分包括:火災(zāi)探測(cè)、報(bào)警系統(tǒng)、滅火系統(tǒng)、自動(dòng)排煙系統(tǒng)和被動(dòng)防火(如防火隔離)。澳大利亞消防工程指導(dǎo)守則提出了工程法規(guī)依據(jù)了新的工作標(biāo)準(zhǔn),即澳大利亞消防工程法規(guī)。在這個(gè)方法的指導(dǎo)下,為燃煙、燃燒但無火花的火焰、和燃燒又有火焰建立防火安全性能評(píng)估。消防系統(tǒng)的工作情況(即探測(cè)概率、滅火或控制火災(zāi))完全根據(jù)各個(gè)特殊系統(tǒng)運(yùn)行可靠性來預(yù)測(cè)。在這份指導(dǎo)手冊(cè)中可靠性評(píng)估來自一個(gè)專家小組而不是來自實(shí)際數(shù)據(jù)。最后,運(yùn)行可靠性的數(shù)據(jù)分別在日本被兩個(gè)不同的研究小組公布,一個(gè)研究小組涉
11、及東京從1990-1997年間的火災(zāi)事故評(píng)估東京消防處1997。另一個(gè)研究小組涉及日本全國從早期到 1978年為止的火災(zāi)事故報(bào)告評(píng)估研究渡邊 1979。表1概述了這些研究提供了可靠的估計(jì)。單獨(dú)的可靠性估計(jì)存在個(gè)別差異取決于這些估計(jì)所用的參數(shù)。因?yàn)橄老到y(tǒng)需要準(zhǔn)確預(yù)測(cè)未來的運(yùn)行性能,從這些研究上導(dǎo)致的可靠性變化,將引起結(jié)果的顯著改變。此外,不確定性伴隨著一種單一的可靠性評(píng)估或者在這些推導(dǎo)可靠性的方法中存在某種潛在的偏見,可能限制它們?cè)谙老到y(tǒng)中研究運(yùn)行可靠性或可靠性性能的指導(dǎo)作用。表1:消防系統(tǒng)運(yùn)行可靠性評(píng)估的公告(成功率)由于在一般的文獻(xiàn)中可靠性估計(jì)的使用性有限,審查文獻(xiàn)是擴(kuò)展了它的作用在(1
12、)建立一個(gè)完善的原理,該原理是關(guān)于被認(rèn)為能影響可靠性的三種策略,并且(二)確定并評(píng)價(jià)關(guān)系到單獨(dú)系統(tǒng)可操作性和故障率的一定數(shù)據(jù)。自動(dòng)滅火系統(tǒng)(即 灑水系統(tǒng))表2概述了一些研究報(bào)告估計(jì),評(píng)價(jià)實(shí)際火災(zāi)事故中自動(dòng)灑水系統(tǒng)滅火的運(yùn)行可靠性。作為一個(gè)群體,這些研究報(bào)告差異很大,在時(shí)間周期、房屋類型和詳細(xì)程度關(guān)系到火災(zāi)的類型和灑水系統(tǒng)設(shè)計(jì)。表2所顯示的自噴系統(tǒng)的運(yùn)行可靠性估計(jì)一般相對(duì)較高,而一些研究提出把火災(zāi)控制或火災(zāi)失效,作為可靠性評(píng)估的一部分,但該報(bào)告的數(shù)據(jù)卻并不一致。因此,運(yùn)行可靠性假定為限噴灑操作。評(píng)估也應(yīng)顯示價(jià)值范圍,暗示不宜使用一個(gè)自噴系統(tǒng)可靠性而不注意數(shù)據(jù)的偏差和一般的從不同數(shù)據(jù)庫不確定性數(shù)據(jù)
13、源相結(jié)合。原預(yù)算表2由可靠性估計(jì)范圍由81.13%到99.5%泰勒maybee,marryat。81%的偏低價(jià)值與泰勒的研究中和一些被kook估計(jì)過高的(即87.6%)的報(bào)告,這些出現(xiàn)重大偏差的數(shù)據(jù)在這些研究中使用。在這兩種研究中,發(fā)生火災(zāi)的次數(shù)十分少,并且在數(shù)據(jù)庫中不區(qū)分自動(dòng)滅火系統(tǒng)和其他的滅火系統(tǒng)。最終maybee和marryat報(bào)告中的99.5%高估計(jì)反映了自噴系統(tǒng)在檢查、檢測(cè)和維修是嚴(yán)謹(jǐn)?shù)暮陀邪缚苫?。在自噴系統(tǒng)可取得的數(shù)據(jù)中,另一個(gè)重要的限制是大部分的自噴系統(tǒng)包括記載噴水的事故。在這些研究中,很有限的事故數(shù)據(jù)也參考了快速反應(yīng)或適宜的噴水技術(shù)。在評(píng)估適宜噴水系統(tǒng)的可靠性時(shí)應(yīng)特別關(guān)注幾個(gè)
14、因素,包括(1)允許復(fù)蓋范圍內(nèi)(2)供水能力較低(3)在火災(zāi)中無遙控或警報(bào)系統(tǒng)的潛力很大。基于此,還有與這些技術(shù)(如維修水平)相關(guān)的其他因素可以直接影響這些類型的自噴系統(tǒng)的運(yùn)行可靠性。另外,還需要解決這些問題時(shí)的系統(tǒng)數(shù)據(jù),但基于后來的觀察和一般住宅一般不太可能保持正常,一些旨在保證住宅自噴系統(tǒng)運(yùn)行可靠性的東西可能被降低?;馂?zāi)探測(cè)或警報(bào)系統(tǒng)表3提供了一份關(guān)于用于住宅系統(tǒng)運(yùn)行可靠性分析的概述,評(píng)估包括平均可能性和95%的置信區(qū)間都是基于HALL1955提供的數(shù)據(jù)所預(yù)估的。平均可靠性估計(jì)的范圍從68%至88%不等。這些標(biāo)準(zhǔn)同托比德爾菲研究所所提供的可靠性數(shù)字相一致。然而,95%的置信區(qū)間的一般范圍為
15、66%至90%。表3:煙霧探測(cè)器的可靠性分析HALL,1955防火分區(qū)依靠各種類型器材的功能例如:門(包括固定器材)、墻壁、地板/天花板、滲透孔、玻璃窗、防火卷簾、防煙材料和建筑物。當(dāng)防火分區(qū)被認(rèn)為是防火計(jì)劃中的重點(diǎn)時(shí),在文獻(xiàn)中有很少的數(shù)據(jù)認(rèn)為單個(gè)組成部分的運(yùn)行作用于防火分區(qū)。單個(gè)為建筑的評(píng)估和運(yùn)行可靠性在WARRIGTON的研究中和澳大利亞消防工程索引中被提到。但這些評(píng)估是完全基于專家的判斷。因此不會(huì)提供更加深入的分析。統(tǒng)計(jì)數(shù)據(jù)和不可靠估計(jì)文獻(xiàn)資料概括了先前部分提供的描述自動(dòng)噴水系統(tǒng)和火災(zāi)探測(cè)可靠性評(píng)估的信息和數(shù)據(jù)。自動(dòng)噴水系統(tǒng)可靠性的數(shù)據(jù)有幾個(gè)出處,火災(zāi)探測(cè)的可靠性評(píng)估僅來自一個(gè)會(huì)議,HA
16、LL1944。這個(gè)會(huì)議包括十年(1983-1992)的可靠性評(píng)估和列出了在文獻(xiàn)中搜到的綜合可靠性研究。這份文件的最初一個(gè)目標(biāo)是提供一個(gè)關(guān)于所研究的系統(tǒng)運(yùn)行可靠性評(píng)估的預(yù)覽。 為自噴系統(tǒng)和火災(zāi)探測(cè),它基于現(xiàn)實(shí)數(shù)據(jù)做了一個(gè)統(tǒng)計(jì)分析。自動(dòng)噴水系統(tǒng)分析表2中關(guān)于自動(dòng)噴水系統(tǒng)可靠性分析,是根據(jù)每一種居住類型來分析的。應(yīng)當(dāng)指出,只有一個(gè)出處MILNE,1959提供了關(guān)于公共建筑和居住房屋的可靠性估計(jì),并且這些早期數(shù)據(jù)沒有提供現(xiàn)代住宅噴頭技術(shù)的可靠性數(shù)據(jù)。圖1的分布直方圖列出了每一個(gè)住宅類型的可靠性估計(jì)。平均值和95%的置信區(qū)間的限制是適合一般住宅(在研究中不區(qū)分商業(yè)建筑、住宅建筑和公共建筑的類別)和商業(yè)建
17、筑,并且適用于綜合樓(商業(yè)、公共建筑、住宅類)的可靠性評(píng)估。這些結(jié)果列在表4。圖1:自動(dòng)噴水系統(tǒng)對(duì)各種住宅類型的可靠性評(píng)估關(guān)于商業(yè)建筑和公共建筑可靠性評(píng)估的平均值控制在其他住宅類型的95%置信區(qū)間內(nèi)。適宜居住和公共建筑的單個(gè)點(diǎn)估計(jì),增加了一些與運(yùn)行可靠性有用的東西,也增加了數(shù)據(jù)庫的容量。用18估計(jì)四個(gè)獨(dú)立的門類。然而,關(guān)于住宅和公共建筑的點(diǎn)估計(jì)不應(yīng)單獨(dú)使用而作出任何結(jié)論。關(guān)于商業(yè)建筑、住宅和綜合建筑的可靠性估計(jì)提供了一些有用的信息?;趯?duì)噴淋系統(tǒng)分析的可利用數(shù)據(jù)是運(yùn)行的可靠性估計(jì)超過88%,如果不考慮商業(yè)建筑,噴淋系統(tǒng)的可靠性可達(dá)到92%以上。然而,判斷這種特殊的噴淋系統(tǒng)與那些評(píng)估中提到系統(tǒng)是
18、否相似是十分重要的。商業(yè)建筑的的可靠性范圍在80%至98%,而一般建筑的為94%至98%?;馂?zāi)探測(cè)系統(tǒng)分析關(guān)于火災(zāi)探測(cè)系統(tǒng)可靠性估計(jì)的數(shù)據(jù)是全面的。這份數(shù)據(jù)跨越了十年,并且每年都做可靠性評(píng)估報(bào)告(反映在表3),它為了各種不同用途的房屋而完成。這里的分析根據(jù)房屋的用途把它們分為幾個(gè)建筑等級(jí)。每種用途的房屋得出數(shù)據(jù)后,然后計(jì)算每種房屋的可靠性估計(jì)。圖2顯示了所有煙霧探測(cè)器關(guān)于全部住宅類型的可靠性估計(jì)。圖2:煙霧探測(cè)器對(duì)各種住宅類型的可靠性估計(jì)如直方圖中所示,數(shù)據(jù)有一個(gè)雙態(tài)分布。因此,為了進(jìn)一步研究兩個(gè)平均值完全不同的數(shù)據(jù)庫,進(jìn)行了一個(gè)方差(變異數(shù))分析。變異數(shù)檢測(cè)了可靠性估計(jì)的平均值和對(duì)一個(gè)給定建
19、筑類型的可靠性影響。圖形代表性的變異數(shù)以最小二乘法的形式在圖3中體現(xiàn)。變異數(shù)影響最終結(jié)果。如圖3所示,三種住宅分類分別有不同的關(guān)于煙霧探測(cè)起的平均可靠性估計(jì)。圖4中包含的直方圖分別描述了每種住宅類型的可靠性估計(jì)。圖3:煙霧探測(cè)系統(tǒng)對(duì)各種住宅類型的可靠性分析時(shí)變異數(shù)的影響這些住宅類型分別在平均可靠性估計(jì)和95%的置信區(qū)間估計(jì)內(nèi)進(jìn)行單獨(dú)分析。結(jié)果列于表5,每種類型的結(jié)果明顯不同。各種住宅類型的置信區(qū)間與自噴系統(tǒng)的可靠性估計(jì)時(shí)的置信區(qū)間不重疊。這就可能使有更多的數(shù)據(jù)用于煙霧探測(cè)器的分析,列于表5中各個(gè)住宅類型的煙霧探測(cè)器的可靠性估計(jì)完全不同,判斷非相關(guān)數(shù)據(jù)差異的原因超出了這個(gè)分析的范圍。分析中所用到
20、的數(shù)據(jù)是在研究中描述為典型系統(tǒng)的,在公開文獻(xiàn)中關(guān)于噴淋系統(tǒng)和煙霧探測(cè)器可靠性的最好數(shù)據(jù)。典型數(shù)據(jù)是一種重要的依據(jù),它用來判斷某種類型的信息是否達(dá)到這種類型的統(tǒng)計(jì)學(xué)分析。分析的結(jié)果應(yīng)該被用來做出推論,但必須在研究相關(guān)資料和測(cè)驗(yàn)它們對(duì)分析系統(tǒng)中使用的特殊安全計(jì)劃的適應(yīng)性以后。然而,總體的接近代表著在解決不同消防系統(tǒng)類別的可靠性時(shí)更高的標(biāo)準(zhǔn),包括注意報(bào)告數(shù)據(jù)中的不確定性和偏差。圖4:煙霧探測(cè)器對(duì)各種住宅類型的可靠性分析分配概要和結(jié)論一份詳細(xì)的文獻(xiàn)摘要和運(yùn)行可靠性分析被用來關(guān)注幾個(gè)消防計(jì)劃的運(yùn)行可靠性,消防計(jì)劃包括:火災(zāi)探測(cè)、自動(dòng)噴水和防火分區(qū)。在這項(xiàng)研究中,運(yùn)行可靠性被定義為消防系統(tǒng)在需要時(shí)運(yùn)行的可
21、靠性估計(jì)。這些出版物的標(biāo)準(zhǔn)不直接在評(píng)估中敘述不確定性或偏差。關(guān)于防火分區(qū),在表1中的運(yùn)行可靠性概述是它的唯一信息。在試圖解決評(píng)估中的不確定性過程中,幾個(gè)火災(zāi)的實(shí)際細(xì)節(jié)研究,煙霧探測(cè)器和自動(dòng)噴水系統(tǒng)的運(yùn)行性能被重新分析,并且報(bào)告數(shù)據(jù)被提取為一個(gè)更加條理的評(píng)價(jià)。沒有發(fā)現(xiàn)防火分區(qū)的相關(guān)數(shù)據(jù),這個(gè)評(píng)價(jià)包括利用常規(guī)統(tǒng)計(jì)方法來評(píng)價(jià)可靠性數(shù)據(jù)和運(yùn)行可靠性的平均估計(jì),還有運(yùn)行可靠性達(dá)到95%的置信區(qū)間范圍。表4和表5概括了這個(gè)分析的結(jié)果。測(cè)試結(jié)果顯示,使用單一標(biāo)準(zhǔn)來評(píng)估一個(gè)消防系統(tǒng)的運(yùn)行可靠性是不恰當(dāng)?shù)?。例如,在?中對(duì)噴淋系統(tǒng)的運(yùn)行可靠性評(píng)估,在商業(yè)建筑中范圍從88%至98%,同時(shí)平均估計(jì)為93%,人口數(shù)量
22、太少(單值)為計(jì)算平均價(jià)值和住宅或公共建筑的置信區(qū)間的限制,但綜合樓計(jì)算的平均可靠性估計(jì)為95%,同時(shí)95%的置信區(qū)間為92%至97%,平均價(jià)值應(yīng)用到可靠性上,基于這個(gè)認(rèn)識(shí)即價(jià)值代表95%置信區(qū)間的平均范圍,它是比較合理的與用來任意衍生的價(jià)值相比。另外,整個(gè)置信區(qū)間的使用和不是最可能的平均值相比,當(dāng)比較系統(tǒng)時(shí)有更加明顯詳實(shí)的信息,因?yàn)樗械南嗨葡到y(tǒng)的可靠性評(píng)估包括比較。這是當(dāng)拿一個(gè)系統(tǒng)同其他許多系統(tǒng)相比較時(shí)一個(gè)公認(rèn)的統(tǒng)計(jì)方法。煙霧探測(cè)器在表5中的運(yùn)行可靠性值有一個(gè)與95%置信區(qū)間相關(guān)聯(lián)的更為緊湊的范圍。這可能是數(shù)據(jù)庫的大小和質(zhì)量以及通過HALL1995來保持結(jié)果的最初說明的一致性所導(dǎo)致的直接后
23、果?;诒?中所體現(xiàn)的結(jié)果,煙霧探測(cè)器的平均值為,對(duì)商業(yè)建筑為72.5%(下界70.2%,上界為73.7%),對(duì)住宅為77.8%(下界75.1%,上界為80.6%),對(duì)公共建筑為83.5%(下界82.3%,上界為84.6%)。煙霧探測(cè)器可靠性的變異結(jié)果進(jìn)一步表明可靠性估計(jì)由為數(shù)據(jù)分析的住宅類型決定(見圖3),煙霧探測(cè)器的最高可靠性與公共建筑有關(guān)。這可能是許多的公共建筑需要更多的維護(hù)和日常系統(tǒng)需求保證的直接后果。這一分析方法能很容易的應(yīng)用到其他消防系統(tǒng)的運(yùn)行可靠性評(píng)估。但是,應(yīng)當(dāng)指出文獻(xiàn)中數(shù)據(jù)的可靠性是一個(gè)重要的因素。值得注意的是數(shù)據(jù)在內(nèi)容和形式上的巨大變化,在學(xué)習(xí)報(bào)告和研究時(shí)這是努力的一部分。
24、這項(xiàng)研究提供了一個(gè)十分廣泛的初步嘗試去描述消防系統(tǒng)的運(yùn)行可靠性。調(diào)查報(bào)告需要大量的數(shù)據(jù)來改變數(shù)據(jù)庫。這種努力的重心在取得更加具體的數(shù)據(jù),系統(tǒng)的廣泛人口能為消防系統(tǒng)運(yùn)行可靠性的巨大改善提供基礎(chǔ),從而引起設(shè)計(jì)工程師的興趣,另外這項(xiàng)技術(shù)對(duì)工程師基于高速發(fā)展的設(shè)計(jì)理念的性能分析也是必要的。外文出處:http:/10附錄二:外文資料原文Estimates of the Operational Reliability of Fire Protection SystemsFor the past three years,the National Institute of Standards and Tech
25、nology (NIST) has been working to develop a new encryption standard to keep government information secureThe organization is in the final stages of an open process of selecting one or more algorithms,or data-scrambling formulas,for the new Advanced Encryption Standard (AES) and plans to make adecisi
26、on by late summer or early fallThe standard is slated to go into effect next year Richard W. Bukowski,P.E. Senior Engineer MST Building and Fire Research Laboratory Gaithersburg,MD 20899-8642 USA Edward K. Budnick,P.E.,and Christopher F. Scheme1 Vice President Chemical Engineer Hughes Associates,Inc
27、 Hughes Associates,Inc. Baltimore,MD 21227-1652USA Baltimore,MD 2 1227-1652USA INTRODUCTION BackgroundFire protection strategies are designed and installed to perform specific functions. For example,a fire sprinkler system is expected to control or extinguish fires: To accomplish this,the system spr
28、inklers must open,and the required amount of water to achieve control or extinguishment must be delivered to the fire location. A fire detection system is intended to provide sufficient early warning of a fire to permit occupant notification and escape,fire service notification,and in some cases act
29、ivation of other fire protection features (e.g.,special extinguishing systems,smoke management systems). Both system activation (detection) and notification (alarm) must occur to achieve early warning. Construction compartmentation is generally designed to limit the extent of fire spread as well as
30、to maintain the buildings structural integrity as well as tenability along escape routes for some specified period of time. In order to accomplish this,the construction features must be fire “rated” (based on standard tests) and the integrity of the features maintained. The reliability of individual
31、 fire protection strategies such as detection,automatic suppression,and construction compartmentation is important input to detailed engineering analyses associated with performance based design. In the context of safety systems,there are several elements of reliability,including both operational an
32、d perfornzzsance reliability. Operational reliability provides a measure of the probability that a fire protection system will operate as intended when needed. Performance reliability is a measure of the adequacy of the feature to successfully perform its intended hnction under specific fire exposur
33、e conditions. The former is a measure of component or system operability while the latter is a measure of the adequacy of the system design. The scope of this study was limited to evaluation of operational reliability due primarily to the form of the reported data in the literature. In addition to t
34、his distinction between operational and performance reliability,the scope focused on unconditional estimates of reliability and failure estimates in terms offail-dangerous outcomes. A discussion of these terms is provided later in the paper. Scope This paper provides a review of reported operational
35、 reliability and performance estimates for (1) fire detection,(2) automatic suppression,and to a limited extent (3) construction compartmentation. In general,the reported estimates for fire detection are largely for smoke detectiodfire alarm systems; automatic sprinklers comprise most of the data fo
36、r automatic suppression,and compartmentation includes compartment fire resistance and enclosure integrity. It should be noted that in some cases the literature did not delineate beyond the general categories of “fire detection” or “automatic suppression,” requiring assumptions regarding the specific
37、 type of fire protection system. Several studies reported estimates of reliability for both fire detection and automatic sprinkler system strategies. However,very little information was found detailing reliability estimates for passive fire protection strategies such as compartmentation. A limited s
38、tatistical based analysis was performed to provide generalized information on the ranges of such estimates and related uncertainties. This latter effort was limited to evaluation of reported data on detection and suppression. Insufficient data were identified on compartmentation reliability to be in
39、cluded. This paper addresses elements of reliability as they relate to fire safety systems. The literature search that was performed for this analysis is reviewed and important findings and data summarized. The data found in the literature that were applicable to sprinkler and smoke detection system
40、s reliability were analyzed,with descriptive estimates of the mean values and 95 percent confidence intervals for the operational reliability of these in situ systems reported. ELEMENTS OF RELIABILITY ANALYSIS There is considerable variation in reliability data and associated analyses reported in th
41、e literature. Basically,reliability is an estimate of the probability that a system or component will operate as designed over some time period. During the useful or expected life of a component,this time period is “reset” each time a component is tested and found to be in working order. Therefore,t
42、he more often systems and components are tested and maintained,the more reliable they are. This form of reliability is referred to as unconditional. Unconditional reliability is an estimate of the probability that a system will operate “on demand.” A conditional reliability is an estimate that two e
43、vents of concern,i.e.,a fire and successful operation of a fire safety system occur at the same time. Reliability estimates that do not consider a fire event probability are unconditional estimates. Two other important concepts applied to operational reliability are fuiled-safe and failed- dangerous
44、. when a fire safety system fails safe,it operates when no fire event has occurred. A common example is the false alarming of a smoke detector. A fire safety system fails dangerous when it does not function during a fire event. In this study,the failed-dangerous event defines the Operational probabi
45、lity of failure (1-reliability estimate). A sprinkler system not operating during a fire event or an operating system that does not control or extinguish a fire are examples of this type of failure. The overall reliability of a system depends on the reliability of individual components and their cor
46、responding failure rates,the interdependencies of the individual components that compose the system,and the maintenance and testing of components and systems once installed to veri operability. All of these factors are of concern in estimating operationaz reliability. Fire safety system performance
47、is also of concern when dealing with the overall concept of reliability. System performance is defined as the ability of a particular system to accomplish the task for which it was designed and installed. For example,the performance of a fire rated separation is based on the construction components
48、ability to remain intact and provide fire separation during a fire. The degree to which these components prevent fire spread across their intended boundaries defines system performance. Performance reliability estimates require data on how well systems accomplish their design task under actual fire
49、events or full scale tests. Information on performance reliability could not be discerned directly from many of the data sources reviewed as part of this effort due to the form of the presented data,and therefore,it is not addressed as a separate effect. The cause of failure for any type of system i
50、s typically classified into several general categories: installation errors,design mistakes,manufacturing/equipment defects,lack of maintenance,exceeding design limits,and environmental factors. There are several approaches that can be utilized to minimize the probability of failure. Such methods in
51、clude (1) design redundancy,(2) active monitoring for faults,(3) providing the simplest system (i.e.,the least number of components) to address the hazard,and (4) a well designed inspection,testing,and maintenance program. These reliability engineering concepts are important when evaluating reliabil
52、ity estimates reported in the literature. Depending on the data used in a given analysis,the reliability estimate may relate to one or more of the concepts presented above. The literature review conducted under the scope of this effort addresses these concepts where appropriate. Most of the informat
53、ion that was obtained from the literature in support of this paper were reported in terms of unconditional operationaZ reliability,i.e.,in terms of the probability that a fire protection strategy will not faiZ dangerous. LITERATURE REVIEW A literature search was conducted to gather reliability data
54、of all types for fire safety systems relevant to the protection strategies considered: automatic suppression,automatic detection,and compartmentation. The objective of the literature search was to obtain system-specific reliability estimates for the performance of each type of fire safety system as
55、a function of generic occupancy type (e.g.,residential,commercial,and institutional). Sources of information included national fire incident database reports,US Department of Defense safety records,industry and occupancy specific studies,insurance industry historical records and inspection reports d
56、ocumented in the open literature,and experimental data Reports on experimental work and fire testing results were utilized only when fire detection,automatic suppression,or compartmentation strategies were explicitly evaluated. Tests of systems used for qualification,approval,or listing were also re
57、viewed for information on failure modes. Published data from the United Kingdom,Japan,Australia,and New Zealand were included. General Studies Several broad based studies were identified that reported reliability estimates for fire detection and fire suppression systems as well as construction compa
58、rtmentation. These included (1) the Warrington Fire Research study 1996 in the United Kingdom,(2) the Australian Fire Engineering Guidelines Fire Code Reform Center,19961,(3) a compilation of fire statistics for Tokyo,Japan Tokyo Fire Department,19971,and(4)results from a study of in situ performance of fire protection systems in Japan Watanabe,19791.The Warrington Fire Research study addressed the reliability of fire safety systems and the interaction of
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請(qǐng)下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請(qǐng)聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會(huì)有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 人人文庫網(wǎng)僅提供信息存儲(chǔ)空間,僅對(duì)用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對(duì)用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對(duì)任何下載內(nèi)容負(fù)責(zé)。
- 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請(qǐng)與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對(duì)自己和他人造成任何形式的傷害或損失。
最新文檔
- 最高額度抵押借款合同樣本
- 2024個(gè)人物品買賣合同范文
- 地鐵隧道廣告投放協(xié)議
- 個(gè)人私人借款協(xié)議
- 店鋪合作經(jīng)營合同范例
- 2024年購銷合同定義
- 勞動(dòng)合同書樣式范本
- 企業(yè)委托資產(chǎn)管理協(xié)議書
- 合租房屋合同樣本
- 設(shè)計(jì)委托協(xié)議書模板
- 律師事務(wù)所金融業(yè)務(wù)部法律服務(wù)方案
- 施工人員計(jì)劃配置表(共1頁)
- 裝修工程施工進(jìn)度計(jì)劃表excel模板
- 發(fā)電機(jī)組自動(dòng)控制器
- 宿舍管理流程圖
- 骨科復(fù)試問答題
- 新版慢病隨訪表3頁
- 《實(shí)踐論》讀書PPT課件
- 青島版科學(xué)六年級(jí)上冊(cè)《齒輪》教學(xué)設(shè)計(jì)
- 《偷影子的人》PPT課件
- 江南大學(xué)鋼結(jié)構(gòu)設(shè)計(jì)期末復(fù)習(xí)題考題附答案
評(píng)論
0/150
提交評(píng)論