风险评估方法程序

1、V /赛科 SECCOCon tract TitleShan ghai Secco Petrochemicals Compa ny LimitedShanghai Ethylene Cracker Co mplexCaojing, Shanghai, P R ChinaDocume nt TitleQUANTITIVE RISK ASSESSMENT PHILOSOPH YDOCUMENT NUMBERPH-00-TSC-SE-0008A02APPROVEDMCR30/08/02PS30/08/02JEF30/08/02AS19/11/02A01FOR APPROVALRM18/06/02JE

2、F21/06/02JEF21/06/02RJCTD22/8/02A00FOR APPROVALRM08/05/02MR08/05/02JEF08/0502RJCTDRJCTDP00PRELIMINARY FOR REVIEWRM10/04/02JEF10/04/02IssueRevIssue or Revisi on Descripti onOrigin byDateCheck byDateApprove byDateApprove byDateThis Docume nt is Owned byAdrian Sambrook (AS)IPMT AuthorityHARD COPIES ARE

3、 UNCONTROLLEDPage 1 of 13SECCOQuan titive Risk Assessme nt PhilosophyPH-00-TSC-SE-0008-A02QUANTITIVE RISK ASSESSMENT PHILOSOPHYTABLE OF CONTENTS1.0 INTRODUCTION1.1 General1.2 Integrated Project Management Team (Ipmt) Strategy1.3 Project documents2.0 SCOPE OF WORK2.1 General2.2 Approach to Work3.0 QR

4、A METHODOLOGY3.1 RATIONALE FORQRA3.2 Methodology3.2.1 Hazard Ide ntificati on and Scree ning3.2.2 In cide nt Seen ario Developme nt3.2.3 Freque ncy and Probability An alysis3.2.4 Co nseque nee Modelli ng3.2.5 Fatality Estimatio n3.2.6 Risk Evaluatio n3.2.7 What if? An alysis3.2.8 Human Factors3.3 Co

5、st Benefit Analysis and Demonstration of ALARP3.3.1 Approach3.3.2 Methodology3.4 QRA Flowchart3.4.1 Flow Chart4.0 DOCUMENTATION DELIVERABLES5.0 QRA REPORT ATTACHMENTSQuan titive Risk Assessme nt PhilosophyPage 11 of 1330/08/02INTRODUCTION1.01.11.2G ENERALThe purpose of this docume nt is to set out t

6、he methodology of Quan titive Risk Assessme nt approach for all Process Un its of the SECCO facility. The document has been developed in order to create a global cross-discipline guide for the development of the process derivatives plants and offsites in volved in this project.The Philosophy shall b

7、e used as a guide by all con tractors in the SECCO developme nt and as such will be subject of in put from all concern ed. It will be arran ged as a support for the Shan ghai Secco Petrochemical Compa ny Ltd, SECCO IPMT and Chinese Legislative requirements to ensure that the design process in corpor

8、ates the best available practice with the optimisati on of resource and cost.As a link to the responsibilities of the Operator,Shanghai SeccoPetrochemical Compa ny Ltd an In tegrated Project Man ageme nt Team (IPMT) has bee n established to man age the Shan ghai Ethyle ne Cracker Complex (SECCO) pro

9、ject and it s engin eeri ng con tractors.The QRA docume nt shall li nk the fire hazard assessme nt requireme nts, and any Quantitative Risk Assessment process, to the design development by ensuring that reliable and effective safety and emergency systems are in corporated. This will provide an overa

10、ll system, which will help to mini mise the loss of life, producti on, capital in vestme nt and damage to the en vir onment should an accide ntal eve nt occur.This document while providing the basic safety design guidelines for the Project does not attempt to cover in detail every aspect of safety d

11、esign. Referenee should be made therefore, to specific discipline philosophies and specifications as appropriate.The philosophy does not relieve personnel of Shanghai Secco Petrochemical Compa ny Ltd. SECCO IPMT, the Main En gi neeri ng Con tractors and their subcontractors and Suppliers from their

12、responsibilities for the safe development of the design under current applicable legislative requirements pertaining to the developme nt.INTEGRATED PROJECT MANAGEMENT TEAM (IPMT) STRATEGYThe IPMT strategy for Quantitive Risk Assessment in accordanee with the Concept Safety Evaluation shall be is to

13、develop, within a Health, Safety and En vir onmen tal backgro und, a philosophy, in corporati ng sta ndards and specificati ons in order that a com mon and uniform approach is adopted to en sure across the plot sta ndardisati on.By adopt ing a com mon sta ndard it is inten ded to create a situati on

14、 where facilities are, assessed, engineered and supplied/installed on a uniform basis and hence negate a situation which has arrived at a differing engineering soluti on and differi ng comp onent parts.1.3Project DocumentsActive and Passive Fire Protect ion PhilosophyCon cept Safety Evaluati on Repo

15、rtTech nical HSE Pla nHazardous Area Classificati on PhilosophyEn vir onmen tal Assura nee StrategyIn strume nt and Con trol PhilosophyDistributed Con trol SystemPlant Layout PhilosophyGen eral Site In formati on: Meteorological, Geological & Utilities DataUnit Equipme nt. Line & In strume nt Number

16、i ng ProcedureFire :& Gas System Specificati onPH-00-TSC-TE-0003RE-00-TSC-SE-0001PL-00-TSC-SE-0001PH-00-TSC-SE-0001ST-00-TSC-SE-0004PH-00-TSC-CI-0003SD-00-TSC-CI-0004PH-00-TSC-PP-0001SP-00-TSC-PR-0001PR-00-TSC-PR-0001SD-00-TSC-0010ST-00-TIJ-SE-0001Risk Acceptability Criteria2.0SCOPE OF WORK2.1G ENER

17、ALQua ntified Risk Assessme nts (QRA) are to be performed for the SECCO Project main process ISBL Teams, Olefins, Styrenics, Poleolefins, Acrylonitrile and Methyl Methacreylate to assess the consequences of identified major hazards particularly, those which could result in harm to people and or the

18、en vir onment.The analysis shall be based on the updated Approved for Design (AFD) in formati on for each un it of the project.The Concept Safety Evaluation (CSE) Report shall be considered as the initial pre-assessme nt docume nt to any QRA Report.The QRA Reports shall determ ine In dividual Risk (

19、IR) and pote ntial loss of life for the SECCO Project workforce and in the surrounding area up to 1.5 km. The QRA is to dem on strate that the safety measures to be provided reduce the risks to As Low As Reaso nably Practicable (ALARP).The in dividual Quan titive Risk Assessme nts shall be prepared

20、in accorda nee with the following parameters.2.1.1Hazard Ide ntificati on and Scree ningIdentification of the potential hazards based on the Concept Safety Evaluation, HAZOPS and prelimi nary desig n docume ntati on provided from the in dividual con tractors desig n and product ion of a hazard list.

21、2.1.2In cide nt Seen ario Developme ntBased on the Process Un it hazard list develop defi nitive eve nt seen arios for subseque nt an alysis.2.1.3Freque ncy and Probability An alysisAssess the freque ncy and probability of each eve nt sce nario using published data and any other applicable data. Dat

22、a will en compass as a minimum release frequency data as a function of hole size from equipment and pipework andfittings and ignition probabilities derived from validated historical sources and models.2.1.4Con seque nee Modelli ngDevelop models to establish the con seque nces for each eve nt sce nar

23、io.2.1.5Safety Function Impairme nt Estimati onFrom each eve nt establish the likely impairme nt or vuln erability of the functionality of safety systems by SIL (Safety Integrity Studies) and shall include Unin terrupted Power Supply (UPS) In tegrity.2.1.6Fatality Estimati on2.1.7Estimate likely fat

24、alities aris ing from each ide ntified eve nt.Risk Evaluati on2.1.8Determi ne in dividual risk and pote ntial loss of life from the fatalities and eve nt probabilities.What if? An alysis (Fu ndame ntals of QRA)Quan tified Risk Assessme nt (QRA) may be in itially defi ned asthe qua ntitiveevaluation

25、of the likelihood of undesired events and the likelihood of harm or damage being caused, together with the value judgeme nts made concerning the sig nifica nee of the results.This procedure in volves a series of specific stages, as follows:Ide ntificati on of un desired eve nts. An alysis of the mec

26、ha ni sms by which un desired eve nts could occur.Con siderati on of the exte nt of any harmful effects.* Con siderati on of the likelihood of the un desired eve nts and the likelihood of specific detrime ntal outcomes.* Judgeme nts about the sig nifica nee of the ide ntified hazards and estimated r

27、isks.In this extent consequeneeshall refer to a hazardous condition, eg a toxic gas2.1.9concen trati on or dose, thermal radiati on, explosi on overpressure, and their resultant effects on people and property etc. Risk refers to the likelihood of a stated level of harm or damage aris ing and is a co

28、mb in ati on of freque ncy and con seque nee, tak ing into acco unt the probability of exposure (say of a pers on, or group of in dividuals) and vuln erability to the hazard.Demo nstratio n of ALARP(As Low As Reaso nable Practicable)2.1.10Each QRA report shall contain a secti on to dem on strate tha

29、t risks to people and or the en vir onment are ALARP.Prese ntati on of ResultsThe prese ntati on of results shall be in a spreadsheet format with the usual facility to produce results as bar charts, pie charts, risk con tours, methods of con seque nee modelli ng.A hard (paper) copy of the QRA model

30、in cludi ng an electro nic vers ion (Word) of the final report shall be provided as a deliverable with the final reports produced by in dividual eon tractors.The QRA Reports shall be issued duri ng the detail desig n phase of the projectto en able in corporati on of any desig n cha nges duri ng the

31、desig n phase of the project un its.2.2A pproach to WorkThe work shall be carried out in two parts: The initial analysis and draft report shall be carried out following an initiation meet ing and collect ion of the n ecessary data collated from the Con cept Safety Evaluati on and process in formati

32、on. A final an alysis and report shall the n be prepared duri ng the detailed desig n phase for each Process Un it (eg Olefi ns) by the Desig n Con tractor for that unit.3.03.1QRA METHODOLOGYRationale for QRAQRA represents a systematic approach to the identification, estimation and evaluati onof haz

33、ards associated with particularin dustrialin stallati ons,processes and operations. The overall process of QRA is not a precise scientific exercise. The nu merical risk levels predicted are estimates, subject to in here nt un certa in ties. QRA is not inten ded as a mecha ni stic nor automatic tech

34、ni cal means of decisi on making. In stead, its proper role is as a decisi on-aidi ng tool, to collate and structure technical information on the likelihood and consequences of pote ntial accide ntal eve nts and to permit value judgeme nts on their sig nifica nee.By this means, the technique improve

35、s the consistency and quality of risk man ageme nt in selected areas of applicati on.The QRA shall be to quantify and assess the risks to persons in accordance with the directives of Secco, established from the Concept Safety Evaluation in the following Process Units:* Olefi ns* Styre nics* Polyolef

36、i ns* Acrylo nitrile* Methyl Methacrylatearising from major hazards and to ensure that they comply with the Risk Acceptability Criteria as stated in Document No. ST-00-TIJ-SE-0001 and can be dem on strated to be As Low As Reas on ably Practicable (ALARP).The Desig n Con tractor for each part of the

37、Process shall be resp on sible for produci ng the Quan titive Risk Assessme nt for that part of the process.This gen eric methodology in dicates the approach to the work required in each QRA Report.3.2M ETHODOLOGYThe methodology shall in volve the follow ing nu mber of logical seque ntial steps as e

38、xpla ined in Section 2:Hazard Ide ntificati on and Scree ning.* In cide nt Seen ario Developme nt.* Freque ncy and Probability An alysis.Con seque nee Modelli ng.Safety Function Impairme nt Estimati on.Fatality Estimati on.Risk Evaluati on.What if? an alysis.Demo nstrati on of ALARP.3.2.1* Prese nta

39、ti on of Results.Hazard Ide ntificati on and Scree ningPotential hazards shall be identified and ranked according to the severity of their consequences and potential for escalation. The Top Events shall be determinedfrom the Con cept Safety Evaluati on by Secco and in dicated to the Con tractors Des

40、ign Safety Engineers. Minor hazards are excluded from further analysis. Major hazards form a set of Top Events to be analysed by QRA. Techniques such as HAZOP (Hazard and Operability Study) or FMEA may prove useful in identifying possible Top Events . However, experienee and judgement are by far the

41、 most effective methods for gen erat ing them. Top Eve nts are expected to in clude, but not be limited to: Leaks from process equipme nt or pipework., eg flammable hydrocarb on vapours and liquids, toxic vapours.* Vehicle collisio n with piperacks or similar in cide nts* Dropped objects.3.2.2* Occu

42、pati onal accide nts.In cide nt Seen ario Developme ntEach Top Eve nt is further developed into In cide nt Seen arios result ing in a full range of possible outcomes ( End Events). This development process shall be carried out by mea ns of Eve nt Trees.The eve nt trees are con structed by con sideri

43、 ng a nu mber of in termediate eve nts such as:Immediate ign iti on?Gas detect ion failureFire detecti on failureESD failureBlowdow n failureEach of these eve nts(questi ons) can have two outcomes (an swers), yes or no, giv ing two bran ches to which probabilities are assig ned.For modelli ng purpos

44、es,Top Eve nt -to- End Eve nt paths that have similar ultimatecon seque nces may be aggregated and represe nted by sin gle in cide nt seen arios. Freque ncies of multiple eve nts may, by this means, be summated and assig ned to a relatively small number of distinct and representative scenarios.3.2.3

45、 Freque ncy and Probability An alysisThe frequencies of top events may be obtained from statistical data having a historical basis such as E&P Forum Data. Alter natively, where historical data is abse nt, these freque ncies can be derived by means of Fault Trees, using gen eric equipme nt failure ra

46、tes from the OREDA and SRD Databases.Freque ncies or probabilities of equipme nt failure or in cide nt occurre nee, used in fault and eve nt trees, are either extracted from gen eric databases such as OREDA or derived from engin eeri ng judgeme nt.Assumpti ons regard ing the operati on and maintenan

47、ce of the facilities that affect the con struct ion of fault or eve nt trees should be listed.3.2.4 Con seque nee Modelli ngHazard regi ons for each in cide nt seen ario shall be calculated using appropriate con seque nee models. For hydrocarb on eve nts, these regi ons equate to levels of gas or sm

48、oke concen trati on, fire radiati on or explosi on over-pressure, depe nding on the in cide nt seen ario.The escalation potential of incident scenarios shall then be estimated taking into acco unt the corresp onding failure criteria forprocess equipme nt and structuresun der thermal or blast loadi n

49、g.3.2.5 Fatality Estimati onThe probability of death and number of fatalities at representative locations is estimated for each in cide nt which shall also in clude any subseque nt escalati on.These shall be based on personnel exposure criteria, which shall define the effects of thermal radiati on,

50、overpressure, smoke and gas on huma ns. The fatality estimation shall take into account the probable personnel distribution and the inten ded pla nt operati ng procedures.3.2.6 Risk Evaluati onThe frequencies and the consequences of each scenarioshall be combined toform the required measure of risk.

51、In dividual risk (Site Operative on Site)In dividual on site risk is the risk that will be experie need by an in dividual worker in a given time period. It shall reflect the severity of the hazards and the amount of time the in dividual spe nds in proximity to them. The in dividual risk shall be pre

52、se nted as:In dividual-specific In dividual Risk (derived from Locati on-specific In dividualRisk). This in dicates the risk for particular groups of workers (e.g. operators, maintainers, clerical), taking into account the time they spend on site.In dividual risk (off site)In dividual off site risk

53、is the risk experie need by pers ons liv ing, work ing or passing near the SECCO Complex. It reflects the severity of the hazards and the amount of time the in dividual spe nds in proximity to them. In dividual off site risk is prese nted as:In dividual-specificRisk (derived from Locati on-specificI

54、n dividualRisk).In dividual-specific Risk shall in dicate the risk for particular sect ions of the public (e.g. those liv ing or work ing n ear the pla nt, those pass ing by the pla nt boun dary), tak ing into acco unt the time they are exposed.Societal riskSocietal risk is the risk experieneed by a

55、ll persons on and off site. It shall reflect the severity of the hazards as well as the number of people exposed to them. Societal risk shall be prese nted as: Pote ntial Loss of Life (PLL) calculated for both on site and offsite.Manning distributions used to assess the lives at risk on site from an

56、y given sce nario shall be extracted take n from the Plant Manning Philosophy docume nts.3.2.7 What if? An alysisThe effects of desig n opti ons on the summated risks shall the n be assessed. At this stage, the resulting risk measures may not be the only factors used in reachi ng decisi ons.3283.33.

57、The variations of the QRA process shall be assessed by considering pessimistic and optimistic in put (upper and lower boun d) values for the major con tributors to risk. Un certa in ty an alysis should provide an in dicati on of the con fide nee limits of the risk summati on and may also be used to en sure the results are stable, i.e. a small cha nge in one of the in put variables does not cause a disproporti on ately large cha nge in any of the final risk measures.Huma n FactorsThe effect of Huma n Factors is an issue that shall be addressed by the QRA model. It is accepte