【正文】 n all probable fire scenarios. ? A prehensive fire risk assessment can be expressed by the following equation: () ? 要注意的是，火災(zāi)風(fēng)險(xiǎn)評(píng)估不僅包括對(duì)人員生命風(fēng)險(xiǎn)的評(píng)估，還可能包括對(duì)財(cái)產(chǎn)損失、對(duì)經(jīng)營(yíng)或生產(chǎn)的影響等造成損失的評(píng)估。 ? Pi 是某一個(gè)火災(zāi)場(chǎng)景 i 發(fā)生的可能性 。 ? 當(dāng)然在建筑中發(fā)生火災(zāi)的方式不止一種，那么對(duì)人員的風(fēng)險(xiǎn)通常要基于所有可能的火災(zāi)場(chǎng)景來(lái)進(jìn)行評(píng)估。 ? C 是這個(gè)特定火災(zāi)場(chǎng)景造成后果預(yù)計(jì)導(dǎo)致的死亡人數(shù)。 ? 它所應(yīng)用到的基本原理與其他領(lǐng)域風(fēng)險(xiǎn)評(píng)估的原理是一致的。 ? 這部分內(nèi)容不是本課程的授課內(nèi)容，將在 《 建筑防火性能化設(shè)計(jì) 》 課程中講述；而在了解火災(zāi)各個(gè)過程和階段基本特征的基礎(chǔ)上，建立相應(yīng)火災(zāi)場(chǎng)景，分析火災(zāi)場(chǎng)景發(fā)生的可能性，是本課程的主要內(nèi)容。 ? A fire scenario involves the projection of a set of fire events, all of which are linked together by whether the fire protection measures succeed or fail. The probability of a fire scenario is dependent on the individual probabilities of success or failure of fire protection measures. ? 對(duì)人員的風(fēng)險(xiǎn) (risk)既決定于能夠?qū)θ藛T產(chǎn)生損害(harm)的火災(zāi)場(chǎng)景發(fā)生的可能性，又決定于火災(zāi)場(chǎng)景或者說火災(zāi)場(chǎng)景產(chǎn)生的后果 (consequence )對(duì)人員造成損害的程度或水平 (level of harm )。 ? 一個(gè)火災(zāi)場(chǎng)景 (fire scenario )由一系列的火災(zāi)中的事件組成，這些火災(zāi)事件是推測(cè)可能在火災(zāi)過程中發(fā)生的事件，將某些防、滅火技術(shù)或管理措施的成功或失效 /失敗的過程連綴起來(lái)，就能夠形成一個(gè)火災(zāi)場(chǎng)景。? 本章引入火災(zāi)風(fēng)險(xiǎn)評(píng)估的基本概念 ? 火災(zāi)風(fēng)險(xiǎn)評(píng)估－ fire risk assessment 指對(duì)火災(zāi)－人們所不希望發(fā)生的這類事故的后果，帶給人員和財(cái)產(chǎn)的風(fēng)險(xiǎn)的評(píng)估。 綜述 ? Basic concepts of fire risk assessment will be introduced in this chapter. ? The term fire risk assessment refers to assessing risks to both people and property as a consequence of unwanted fires. overview ? In a simple risk assessment the probability of a certain unwanted fire scenario is considered and the consequence of that scenario are explored. ? In a prehensive risk assessment all probable unwanted fire scenarios and their consequences are considered. ? 在簡(jiǎn)單的火災(zāi)風(fēng)險(xiǎn)評(píng)估過程中，僅對(duì)某些或某類火災(zāi)場(chǎng)景發(fā)生的可能性和結(jié)果進(jìn)行分析和評(píng)估； ? 在全面或綜合的火災(zāi)風(fēng)險(xiǎn)評(píng)估過程中，對(duì)所有的可能火災(zāi)場(chǎng)景發(fā)生的可能性或結(jié)果進(jìn)行分析和評(píng)估。 ? 因此一個(gè)火災(zāi)場(chǎng)景發(fā)生的可能性 (probability)決定于這一系列事件中每一個(gè)防、滅火技術(shù)或管理措施的成功或失效 /失敗的可能性。 ? 通常應(yīng)用火勢(shì)增長(zhǎng)、煙氣傳播、人員疏散、建筑結(jié)構(gòu)響應(yīng)和消防人員滅火效能等模型來(lái)對(duì)火災(zāi)場(chǎng)景的結(jié)果進(jìn)行計(jì)算和模擬。 ? The risk to the occupants depends not only on the probability of the fire scenario that can lead to harm to the occupants, but also the level of harm to the occupants as a result of the consequence of that scenario. The consequence of a fire scenario can be assessed by using timedependent modeling of fire and smoke spread, occupant evacuation and fire department response. What is Fire Risk Assessment? ? 前面講過，火災(zāi)風(fēng)險(xiǎn)評(píng)估是指對(duì)火災(zāi)－人們所不希望發(fā)生的這類事故的后果，帶給人員和財(cái)產(chǎn)的風(fēng)險(xiǎn)(risk)的評(píng)估。 火災(zāi)風(fēng)險(xiǎn)評(píng)估 (Fire Risk Assessment)的基本概念 ? Fire risk assessment is the assessment of the risks to the people and property as a result of unwanted fires. ? It employs the same basic principles of risk assessment that are used in many other fields. A simple risk assessment considers the probability of the occurrence of a certain unwanted fire scenario and the consequence of that scenario. ? A prehensive risk assessment considers all probable unwanted fire scenarios and their consequences. ? The definition of fire scenario will be discussed in the next section. It involves the linking of anticipated fire events by the success or failure of certain fire protection measures. ? 例如，評(píng)估建筑中的某一個(gè)火災(zāi)場(chǎng)景的后果對(duì)人生命造成的風(fēng)險(xiǎn)，這個(gè)預(yù)計(jì)的生命風(fēng)險(xiǎn)可由 ()式來(lái)表達(dá)： ? 式中 P是這個(gè)特定的火災(zāi)場(chǎng)景發(fā)生的可能性 (頻次或概率， rate或 probability )。 () ? Consider, as an example, the assessment of the expected risk to life to the occupants in a building as a result of one single fire scenario. The expected risk to life can be expressed by the following equation: ? where P is the probability of a certain fire scenario and C is the expected number of deaths as a consequence of that fire scenario. () ? If the probability of a certain fire scenario occurring in a building is once every 20 years, then P = fires per year. ? If the consequence of that fire scenario is two deaths, then C = 2 deaths per fire. ? From Equation , the expected risk to life as a result of that fire scenario is equal to deaths per year, or 1 death every 10 years. ? 比如建筑中某一火災(zāi)場(chǎng)景發(fā)生的可能是２０年一次，則： P = fires per year ? 如果這個(gè)火災(zāi)場(chǎng)景的后果是死亡２人，則 C = 2 deaths per fire ? 從式 ()可知，這個(gè)火災(zāi)場(chǎng)景的預(yù)計(jì)生命風(fēng)險(xiǎn)為 the expected risk to life ＝ deaths per year 或都 1 death every 10 years. 每年 10年死亡１人。那么一個(gè)全面的（ prehensive fire risk assessment ）風(fēng)險(xiǎn)可由 ()式來(lái)表達(dá)： ? 式中的 ∑代表了對(duì)所有可能的火災(zāi)場(chǎng)景進(jìn)行求和。 ? Ci火災(zāi)場(chǎng)景 i 的后果造成的預(yù)計(jì)死亡人數(shù) 。此時(shí)方程 ()和方程()中的后果也相應(yīng)地更換為財(cái)產(chǎn)損失的后果。 ? 火災(zāi)中的一個(gè)事件－ A fire event 是火災(zāi)中發(fā)生的，與起火、火災(zāi)增長(zhǎng)、煙氣傳播、建筑物結(jié)構(gòu)響應(yīng)、人員疏散或消防人員響應(yīng)相關(guān)的事件，如果不是在火災(zāi)中發(fā)生的，或與火災(zāi)的上述過程無(wú)關(guān)的事件，則不視為火災(zāi)中的一個(gè)事件。 ? For example, a fire event can be: a fire develops into a postflashover fire, or the occupants can not evacuate quickly enough and are trapped in the building, or the fire department responds in time and rescues the trapped occupants. ? A fire protection measure is a measure that can be a fire protection system, such as sprinklers and alarms。 ? A simple example of a fire scenario is the following set of events that are linked together by the failure of fire protection measures: ? Another simple example is the following set of events that are linked together by the success of fire protection measures: a fire does not develop into a postflashover fire, the alarm system activates, and the occupants receive the warning signals and evacuate the building. ? 火災(zāi)場(chǎng)景的簡(jiǎn)單例子： ? (1)火災(zāi)發(fā)生了轟燃－報(bào)警系統(tǒng)沒有啟動(dòng)－人員沒有接收到報(bào)警信號(hào)－人員被因于火場(chǎng)中。 ? In realworld fires, fire scenarios are much more plex and the possible number of fire scenarios can be many. ? The number of fire scenarios depends on the number of permutations that can be constructed based on all the fire protection measures that are in place and all the fire events that are anticipated. ? The proper construction of fire scenarios and the proper analysis of the consequence of the fire scenarios, however, are the key to a credible fire risk assessment. ? 就真實(shí)的火災(zāi)而言，火災(zāi)情況要復(fù)雜得多，因此可能的火災(zāi)場(chǎng)景數(shù)量也會(huì)有很多。 ? 合理構(gòu)建火災(zāi)場(chǎng)景并分析其發(fā)生的可能性，對(duì)所建立的火災(zāi)場(chǎng)景后果的盡量符合實(shí)際的分析、計(jì)算或模擬，是決定火災(zāi)風(fēng)險(xiǎn)評(píng)估結(jié)果可信度的關(guān)鍵。 ? The general principle of how fire scenarios can be constructed will be