安全性評價是對被評價單位的設備設施、勞動安全和作業環境、安全生產管理三個方面安全狀況做出全面的、量化的分析和評估。安全性評價分為安全預評價、安全驗收評價、安全現狀綜合評價和專項安全評價，其基本原則是具備國家規定資質的安全評價機構科學、公正和合法地自主開展安全性評價。安全性評價工作是傳統安全管理模式的一種變革，由原來的事后管理轉化為事先管理，是一種較為先進的安全管理方法。在企業發生安全問題之前，經過全面分析、評估，找出問題，予以整改；通過改善勞動環境，健全規章制度，深化安全管理，防止安全事故的發生，提高企業安全生產的基礎。《中華人民共和國安全生產法》第二十四條規定，“生產經營單位新建、改建、擴建工程項目（以下統稱建設項目）的安全設施，必須與主體工程同時設計、同時施工、同時投入生產和使用。” 國家安全生產監督管理局和國家煤礦安全監察局于2003年發布了《安全評價通則》、《安全預評價導則》，加強生產經營單位新建、改建、擴建工程項目安全設施“三同時”工作，規范建設項目安全預評價行為。現在新上馬的火力發電廠，包括企業自備電廠，都必須在可行性研究以后進行安全預評價，由安全生產主管機關對安全預評價報告組織評審通過后，電廠才可以申請開工建設。
     1. 安全預評價的程序安全預評價是根據建設項目可行性研究報告的內容，分析、預測該建設項目存在的危險、有害因素的種類和程度，提出合理可行的安全技術設計和安全管理的建議。安全預評價程序一般包括：準備階段；危險、有害因素識別與分析；確定安全預評價單元；選擇安全預評價方法；定性、定量評價；安全對策措施及建議；安全預評價結論；編制安全預評價報告。
     2. 發電廠主要危險有害因素的辨識和分析
    2.1 重大危險源辨識和分析
    根據《關于開展重大危險源監督管理工作的指導意見》（安監管協調字【2004】56號）的要求，額定蒸汽壓力大于2.5MPa，且額定蒸發量大于等于10t/h的蒸汽鍋爐即構成重大危險源。根據粗略計算，一般功率超過1500kW的機組所配套的鍋爐參數均超過這個標準，因此都構成重大危險源。鍋爐點火助燃使用的輕柴油因閃點較高(大于55℃)，不在GBl8218-2000所列的易燃物質名單中，卻在安監管協調字[2004]56號文規定的范圍內，且在火電廠中儲量較大(一般大于1000t)，應把點火油罐區劃為重大危險源管理；有些大型新建電廠的啟動鍋爐容量較大，運行時間較長，也應該列為重大危險源。鍋爐是具有爆炸危險的特種設備，受國家特種設備監察機構監管。火力發電廠鍋爐一般在較高壓力下運行，其使用的燃料為煤粉，點火燃料使用易燃易爆的0＃～20＃輕柴油，工程配套設備、管線閥門多，工藝復雜。一旦設備、管線、閥門發生破裂，燃料泄漏，鍋爐運行操作不當，極易導致自燃、火災、爆炸、爆管等事故發生；供煤系統也有煤粉塵發生火災、爆炸的可能性。同時，還存在觸電、機械傷害、灼燙、煙氣中毒等危險因素。
     2.2 主要危險因素辨識和分析
    根據發(fa)電(dian)(dian)(dian)(dian)廠工程設備(bei)(bei)的特點(dian)(dian)(dian)，存(cun)在鍋(guo)爐、汽(qi)(qi)輪機(ji)(ji)、蒸汽(qi)(qi)管道、壓(ya)力容(rong)器(qi)等(deng)高(gao)(gao)壓(ya)設備(bei)(bei)，變(bian)配電(dian)(dian)(dian)(dian)等(deng)電(dian)(dian)(dian)(dian)氣(qi)設備(bei)(bei)，以及煤(mei)粉、油(you)類、危(wei)(wei)險(xian)(xian)(xian)化(hua)(hua)(hua)學(xue)品（如鹽(yan)酸、燒(shao)堿、氨水(shui)(shui)等(deng)）等(deng)危(wei)(wei)險(xian)(xian)(xian)物質(zhi)，生產過程中(zhong)(zhong)存(cun)在著火(huo)(huo)(huo)(huo)災、爆(bao)(bao)(bao)(bao)炸(zha)、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、中(zhong)(zhong)毒、高(gao)(gao)處(chu)墜(zhui)落(luo)、車輛(liang)傷(shang)(shang)害(hai)(hai)(hai)等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素。這些危(wei)(wei)險(xian)(xian)(xian)有害(hai)(hai)(hai)因(yin)(yin)(yin)素主要存(cun)在于：電(dian)(dian)(dian)(dian)站(zhan)(zhan)鍋(guo)爐系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；汽(qi)(qi)輪機(ji)(ji)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；電(dian)(dian)(dian)(dian)氣(qi)一次(ci)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；熱(re)(re)工自控系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；化(hua)(hua)(hua)學(xue)制(zhi)(zhi)水(shui)(shui)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)（包括(kuo)制(zhi)(zhi)氫站(zhan)(zhan)）；除灰(hui)渣(zha)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；脫(tuo)硫(liu)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；燃(ran)煤(mei)貯(zhu)運系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；燃(ran)油(you)貯(zhu)運系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)；壓(ya)縮空氣(qi)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)等(deng)。對(dui)(dui)(dui)(dui)(dui)電(dian)(dian)(dian)(dian)站(zhan)(zhan)鍋(guo)爐系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)供煤(mei)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)火(huo)(huo)(huo)(huo)災爆(bao)(bao)(bao)(bao)炸(zha)、點(dian)(dian)(dian)火(huo)(huo)(huo)(huo)油(you)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)火(huo)(huo)(huo)(huo)災爆(bao)(bao)(bao)(bao)炸(zha)、鍋(guo)爐爆(bao)(bao)(bao)(bao)炸(zha)、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、中(zhong)(zhong)毒、高(gao)(gao)處(chu)墜(zhui)落(luo)、車輛(liang)傷(shang)(shang)害(hai)(hai)(hai)等(deng)進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)汽(qi)(qi)輪機(ji)(ji)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)潤滑油(you)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)和抗燃(ran)油(you)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)火(huo)(huo)(huo)(huo)災、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、高(gao)(gao)處(chu)墜(zhui)落(luo)、軸承振(zhen)動、化(hua)(hua)(hua)瓦(wa)、動靜(jing)磨(mo)擦、超(chao)速、大(da)(da)軸彎(wan)曲等(deng)進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)電(dian)(dian)(dian)(dian)氣(qi)一次(ci)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)發(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)火(huo)(huo)(huo)(huo)災、密(mi)封(feng)油(you)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)火(huo)(huo)(huo)(huo)災、變(bian)壓(ya)器(qi)火(huo)(huo)(huo)(huo)災、電(dian)(dian)(dian)(dian)纜火(huo)(huo)(huo)(huo)災、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、高(gao)(gao)處(chu)墜(zhui)落(luo)、發(fa)電(dian)(dian)(dian)(dian)機(ji)(ji)軸承振(zhen)動、化(hua)(hua)(hua)瓦(wa)、動靜(jing)磨(mo)擦、大(da)(da)軸彎(wan)曲、繞組變(bian)形燒(shao)毀(hui)等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)熱(re)(re)工自控系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)由于熱(re)(re)控系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)（DCS、DAS、MCS、SCS、FSSS）故(gu)障可(ke)能引起火(huo)(huo)(huo)(huo)災、爆(bao)(bao)(bao)(bao)炸(zha)、設備(bei)(bei)損壞(huai)，觸(chu)電(dian)(dian)(dian)(dian)、靜(jing)電(dian)(dian)(dian)(dian)、電(dian)(dian)(dian)(dian)磁輻射等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)，還應(ying)(ying)對(dui)(dui)(dui)(dui)(dui)MIS、SIS系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)等(deng)的網絡安(an)全的危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)化(hua)(hua)(hua)學(xue)制(zhi)(zhi)水(shui)(shui)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)（包括(kuo)制(zhi)(zhi)氫系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)），應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)火(huo)(huo)(huo)(huo)災爆(bao)(bao)(bao)(bao)炸(zha)、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、中(zhong)(zhong)毒、高(gao)(gao)處(chu)墜(zhui)落(luo)等(deng)危(wei)(wei)險(xian)(xian)(xian)有害(hai)(hai)(hai)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)除灰(hui)渣(zha)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、高(gao)(gao)處(chu)墜(zhui)落(luo)等(deng)危(wei)(wei)險(xian)(xian)(xian)有害(hai)(hai)(hai)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)脫(tuo)硫(liu)系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、灼(zhuo)(zhuo)燙(tang)、中(zhong)(zhong)毒、高(gao)(gao)處(chu)墜(zhui)落(luo)等(deng)危(wei)(wei)險(xian)(xian)(xian)有害(hai)(hai)(hai)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)燃(ran)煤(mei)貯(zhu)運系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)火(huo)(huo)(huo)(huo)災爆(bao)(bao)(bao)(bao)炸(zha)、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、車輛(liang)傷(shang)(shang)害(hai)(hai)(hai)等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)燃(ran)油(you)貯(zhu)運系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)火(huo)(huo)(huo)(huo)災爆(bao)(bao)(bao)(bao)炸(zha)、觸(chu)電(dian)(dian)(dian)(dian)、機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)、高(gao)(gao)處(chu)墜(zhui)落(luo)、車輛(liang)傷(shang)(shang)害(hai)(hai)(hai)等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)；對(dui)(dui)(dui)(dui)(dui)空氣(qi)壓(ya)縮系(xi)(xi)(xi)(xi)(xi)(xi)(xi)統(tong)(tong)(tong)(tong)，應(ying)(ying)重點(dian)(dian)(dian)對(dui)(dui)(dui)(dui)(dui)觸(chu)電(dian)(dian)(dian)(dian)和機(ji)(ji)械(xie)(xie)(xie)傷(shang)(shang)害(hai)(hai)(hai)等(deng)危(wei)(wei)險(xian)(xian)(xian)因(yin)(yin)(yin)素進(jin)(jin)行分(fen)(fen)(fen)(fen)(fen)(fen)析(xi)(xi)(xi)。