API 580-1
1. The basis for a qualitative probability of failure analysis is: a. consequence b. probability c. POF d. engineering judgment 2. egardless of !hether a more qualitative or a quantitative analysis is used" the POF is determined by t!o main considerations: a. damage mechanisms and inspection effectiveness b. probability # consequence c. damage mechanisms and damage modes d. internal and e#ternal damage $. %ombinations of process conditions and &&&&&&&&&&&&&&&&&&&&& for each equipment item should be evaluated to identify active and credible damage mechanisms: a. pressures and temperatures b. probability # consequence c. materials of construction d. %OF '. (t is important to lin) the damage mechanism to the most li)ely resulting&&&&&&&&&& a. failure analysis b. failure mode c. consequence d. probability *. (n general" an +( program !ill be managed by plant inspectors or inspection engineers" !ho !ill normally manage ris) by managing the POF !ith inspection and maintenance planning. They !ill not normally have much ability to modify the &&&&&&&&&&&&&&&&&&&&: a. process flo! b. failure mode c. POF d. %OF ,. The consequence of loss of containment is generally evaluated as loss of fluid to the&&&&&&&&&&&&&&&&&&&&: a. process flo! b. ground c. e#ternal environment d. unit -. quantitative method involves using a &&&&&&&&&&&&&depicting combinations of events to represent the effects of failure on people" property" the business and the environment : a. POF and %OF b. ris) analysis
c. logic model d. /oore0s a! . esults of a quantitative analysis are usually &&&&&&&&&&&&&&&&&&: a. consequence b. numeric c. logic models d. +uccheim0s a! 13. (t is important to stress that the &&&&&&&&&&&& of the data should match the comple#ity of the +( method used : a. precision b. accuracy c. analysis d. validation 11. The data quality has a direct relation to the relative &&&&&&&&&&&&&&&&& of the +( analysis: a. precision b. detail c. correctness d. accuracy 12. (t is important to stress that the &&&&&&&&&&&& of the data should match the comple#ity of the +( method used : a. precision b. accuracy c. analysis d. validation 1$. &&&&&&&&&&in the hydrocarbon process industry are addressed in P( ',1: a. Pressure 4essel b. Piping (nspection c. 5amage mechanisms d. elief 4alves 16. Failure modes identify ho! the damaged component !ill&&&&&&&&&&&&&&& a. lea) b. crac) c. react to contaminants d. fail 1'. The +( team should consult !ith a &&&&&&&&&&&&&& to define the equipment damage mechanisms: a. +( analyst b. reliability specialist c. corrosion specialist d. engineer
1*. (dentifying trace constituents 7ppm8 in addition to the primary constituents in a &&&&&&&&&&&&ca &&&&&&&&&&&&can n be very very important important as trace trace constituents constituents can can have a significant significant affect affect on the damage mechanisms: a. process b. material c. temperature band d. pressure vessel 1,. Once a credible damage mechanism7s8 has been identified" the associated &&&&&&&&&&&&&& &&&&&&&&&&&&&&& & should also be identified: identified: a. reference b. material c. temperature d. failure mode 1-. (n some cases" damage by one mechanism may progress to a point at !hich a different mechanism ta)es over and begins to dominate the rate of &&&&&&&&&&&&&&&&&&: a. damage b. dissemination c. throughput d. failure 1. The probability analysis in an +( program is performed to estimate the probability of a specific adverse consequence resulting from a &&&&&&&&&&&&&&that occurs due to a damage mechanism7s8: a. damage mechanism b. event c. loss of containment d. failure 23. (t should be noted that damage mechanisms are not the only causes of loss of containment. Other causes of loss of containment could include but are not limited to all 9%9PT the follo!ing: a. seismic activity b. truc) off;loading c. design error d. sabotage 21. (t should be noted that damage mechanisms are not the only causes of loss of containment. Other causes of loss of containment could include but are not limited to all 9%9PT the follo!ing: a. seismic activity b. truc) off;loading c. design error d. sabotage 22. %hanges in the &&&&&&&&&&&&&&&&&&" such as pressure" temperature or fluid composition" resulting from unit abnormal or upset conditions should be considered in the +( assessment:
a. process b. metallurgy c. P<(5 d. design 2$. The &&&&&&&&&&&&&&& of the data should be consistent !ith the +( method used: a. accuracy b. precision c. completeness d. quantification 26. n +( study may use a qualitative" semi;quantitative and=or quantitative approach. fundamental difference among these approaches is the amount and detail of : a. probability and consequence b. accuracy and precision c. input" calculations and output d. damage mechanisms and failure modes 2'. >enerally" a qualitative analysis using broad ranges requires a higher level of judgment" s)ill and understanding from the user than a more &&&&&&&&&&&& approach: a. probabilistic b. quantitative c. consequential d. semi;quantitative 2*. &&&&&&&&&&&&&&&& uses logic models depicting combinations of events that could result in severe accidents and physical models depicting the progression of accidents and the transport of a ha?ardous material to the environment: a. qualitative b. P@ c. A d. semi;quantitative 2,. The semi;quantitative analysis typically requires the same type of data as a quantitative analysis but generally not as: a. quantitative b. detailed c. A d. semi;quantitative 2-. The data quality has a direct relation to the relative &&&&&&&&&&&&&&&&& of the +( analysis: a. precision b. detail c. correctness d. accuracy
2. s is true in any inspection program" data validation is essential for a number of reasons. mong the the reasons reasons for inspection inspection data data quality quality errors are all of of the follo!ing follo!ing 9%9PT 9%9PT : a. outdated dra!ings and documentation b. high corrosion rates c. inspection error d. clerical and data transcription errors $3. Bnfortunately" !hen this &&&&&&&&&&&&&&&&&& step has not been a priority before +(" the time required to do it gets included !ith the time and resources necessary to do a good job on +(" +(" leaving leaving the !rong !rong impression impression !ith !ith some managers managers believing believing that that +( is more time time consuming and e#pensive than it should be : a. precision and accuracy b. planning c. probability # consequence d. data validation $1. The selection and type of &&&&&&&&&&&&&&& used by a facility can have a significant impact on +( results: a. rules and regulations b. codes and standards c. +( analysis d. precision and accuracy $2. Facilities approaching the end of their economic or operating service life are a special case !here &&&&&&&&&&&&&&& can be very very useful. The end of life case for plant operation is about gaining the ma#imum remaining economic benefit from an asset !ithout undue personnel" environmental or financial ris): a. development of damage mechanisms b. creation of integrity operating !indo!s c. removal of high ris) equipment d. application of +( $$. The scope of an +( assessment may vary bet!een an entire refinery or plant and a single component !ithin a single piece of equipment. Typically" +( is done on multiple pieces of equipment 7e.g. an entire process unit8 rather than&&&&&&&&&&&&&&&&&&&&&&: a. on damage mechanisms alone b. on a single component c. on damage factors d. on failure modes alone $6. (f the scope of the +( assessment is a multi;unit facility" the first step in the application of +( is screening of entire process units to ran) &&&&&&&&&&&&: a. absolute ris) b. damage mechanisms c. relative ris) d. probability $'. (t is often advantageous to group equipment !ithin a process unit into &&&&&&&&&&&&&& &&&&&&&&&&&&&&&&&&&& &&&&&& !here common common environment environmental al operating operating conditions conditions e#ist e#ist based based on
process chemistry" pressure and temperature" metallurgy" equipment design and operating history: a. systems" loops" or circuits b. probability" consequence" or ris) c. bacon" lettuce" and tomato d. qualitative" semi;quantitative" or quantitative $*. &&&&&&&&&diagrams for the unit may be used to identify the systems including information about metallurgy" process conditions" credible damage mechanisms and historical problems: a. Piping and (nstrumentation b. +loc) flo! or process flo! c. 4essel and piping d. P%/C $,. (n most plants" a large percentage of the total unit ris) !ill be concentrated in a relatively small percentage of the&&&&&&&&&&&&&&&&&&&&. These potential high;ris) items should receive greater attention in the ris) assessment: a. total unit re!ard b. probability c. consequence d. equipment items $-. Dhen emergency systems 7e.g. flare systems" emergency shutdo!n systems8 are included in the +( assessment" their service conditions during both &&&&&&&&&&&should be considered: a. up and do!n periods b. metallurgies c. routine operations and upset d. intermittent $. The purpose of establishing &&&&&&&&&&&&&&&is to identify )ey process parameters that may impact deterioration: a. ris) matrices b. set points c. operational boundaries d. probability 63. Process conditions during start;up and shutdo!n can have a significant effect on the ris) of a plant especially !hen they are more severe 7li)ely to cause accelerated deterioration8 than normal conditions" and as such should be considered for all equipment covered by the +( assessment. good e#ample is&&&&&&&&&&&&&&&&&&&&: a. >eneral corrosion b. e#ternal corrosion c. @F cid corrosion d. polythionic acid stress corrosion crac)ing 61. The normal operating conditions may be most easily provided if there is a process flo! model or &&&&&&&&&&&&&&&&&&&& available for the plant or process unit:
a. P<(5 b. mass balance c. flo! rates d. process rates 62. %odes and legal requirements vary from one &&&&&&&&&&&&&&&&&&&&to another: a. inspection b. state c. jurisdiction d. PC/ 6$. n +( assessment is a &&&&&&&&&&&&&&&&&&&&&&process: a. team;based b. required c. tiresome d. PC/ mandated 66. From the understanding of &&&&&&&&&&&&&&&&" an inspection program may be designed that optimi?es the use of inspection and plant maintenance resources: a. probability b. consequence c. ris)s d. criteria 6'. The results of managing and reducing ris) are all of the follo!ing 9%9PT: a. avoided losses of containment b. improved safety c. inspection deferral d. avoided commercial losses 6*. educing inspection costs is usually not the primary objective of an&&&&&&&&&&&&&&&&&&" but it is frequently a side effect of optimi?ation: a. +( assessment b. P c. @EOP d. ris) analysis 6,. /ore effective infrequent inspections may be substituted for less effective frequent inspections: a. true b. false c. maybe d. ( don0t )no! 6-. +( focuses efforts on areas !here the &&&&&&&&&&&&&&&&&&&ris)s e#ist : a. lo!est b. greatest c. probable d. ne!est
6. %hanging metallurgy of components can reduce &&&&&&&&&&&: a. PC/ b. P c. %OF d. POF '3. educe or limiting available inventories can reduce by !hat a. PC/ b. P c. %OF d. POF '1. n +( assessment made on ne! equipment or a ne! project" !hile in the design stage" may yield important information on potential ris)s. This may allo! potential ris)s to be &&&&&&&&&& &&&&&&&&&& and have a ris);based ris);based inspection inspection plan plan in place place prior to to actual installat installation: ion: a. minimi?ed by design b. reduced by half c. removed d. mitigated '2. The objective of +( is to direct management0s decision process of prioriti?ing resources to &&&&&&&&&&&&&&&&&&&&&&: a. Cave money b. manage ris) c. fi# stationary equipment d. P@0s and @EOP0s '$. (mpending failure of pressure equipment is not avoided by inspection activities unless the inspection precipitates ris) mitigation activities that change the &&&&&&&&&&&& : a. P b. POF c. %OF d. P@ '6. The primary product of an +( effort should be an &&&&&&&&&&&&& for each equipment item evaluated: a. probability and consequence b. ris) plan c. mitigation plan d. inspection plan ''. For ris)s considered unacceptable" the plan should contain the mitigation actions that are recommended to reduce the &&&&&&&&&&&&&&&& to acceptable levels: a. unmitigated ris) b. ris) plan c. probability and consequence d. ris) matri#
'*. The Fitness;For;Cervice assessment is often accomplished through the )no!ledge and e#pertise of the inspector and engineers involved !hen deterioration is !ithin ',. )no!n acceptable limits" but on occasion !ill require an engineering analysis such as those contained in P(&&&&&&&: a. ',1 b. ', c. '-3 d. ',2 '-. Come ris)s cannot be adequately managed by inspection alone. 9#amples !here inspection may not be sufficient to manage ris)s to acceptable levels are: a. equipment nearing retirement b. failure mechanisms 7such as brittle fracture" fatigue8 c. consequence;dominated ris)s d. all of the above '. The ris);based inspection methodology is intended to complement other ris);based and safety initiatives. The output from several of these initiatives can provide input to the +( effort" and +( outputs may be used to improve safety and ris);based initiatives already implemented by organi?ations. +elo! are e#amples of some of these other initiatives 9%9PT the follo!ing : a. P@ b. OP c. P d. OC@ PC/ *3. Potential ha?ards identified in a P@ !ill often affect the &&&&&&&&&&&&&& side of the ris) equation: a. POF b. %OF c. PC/ d. P%/C *1. The +( system !ill improve the focus of the inspection plan" resulting in a strengthened &&&&& program: program: a. PC/ b. %OF c. POF d.P%/C *2. 9quipment &&&&&&&&&&& programs can provide input to the probability analysis portion of an +( program: a. inspection b. ris) management c. OC@ d. reliability *$. physical condition or release of ha?ardous material that could result from component failure and result in human injury or death" loss or damage" or environmental degradation.
7a8 @a?ard 7b8 oss 7c8 failure *6. imitation of any negative consequence or reduction in probability of a particular event. 7a8 mitigation 7b8 reduction 7c8 residual *'. /ethods that use engineering judgment and e#perience as the bases for the analysis of probabilities and consequences of failure. 7a8 Aualitative ris) assessment 7b8 elative ris) 7c8 ominal ris) **. n analysis that identifies and delineates the combinations of events and estimates the frequency of occurrence for each combination and estimates the consequences. 7a8 Auantitative ris) analysis 7b8 Aualitative ris) analysis7c8 Process ha?ard analysis *,. &&&&&&&&&& uses logic models depicting combinations of events. 7a8 Auantitative ris) analysis 7b8 Aalitative ris) analysis 7c8 Process ha?ard analysis 7a8 Auantitative ris) analysis 7b8 Aualitative ris) analysis *-. Auantitative ris) analysis logic models generally consist of &&&&&&&&&& and &&&&&&&&&& &&&&&&&&&& 7a8 9vent tree and fault tree 7b8 Product trees and loss tree 7c8 i)elihood trees and consequence trees *. &&&&&&&&&& delinate initiating events and combinations of systems successes and failures 7a8 9vent tree 7b8 Fault trees 7c8 logic trees ,3. The accurany of any type of +( analysis depends on !hatG 7a8 Cound methodolgy 7b8 quailty data 7c8 )no!ledgeable personnel
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The accurany of any type of RBI analysis depends on what? Cound methodolgy quailty data )no!ledgeable personnel Fault tress depict what? The system failues repersented in the event can occur. The susceptibilty of each equipment item should be clearly defined for current and projected operating cond co ndit itio ions ns in incl clud udin ing g wha whatt fac facto tors rs? ? 7a8 normal operation 7b8 upset conditions 7c8 normal start up and shut do!n 7d8 idle or out;of;se out;of;service rvice timr 7e8 emergency shutdo!n and subsequent start;up What is is ri risk? is) is the combination of the probability of some event occuring during a time period of intrest and consequences associated !ith the event in mathematical terms.
What is the the equatio equation n of risk? risk? ris)HProbability I consequence is) /anagement is a process to assess ris)" to determine if ris) reduction is required and develop a plan to maintain ris) at an acceptable level. Risk reduction is what? The act of mitigating a )no!n ris) that is deemed to be too high and lo!er to a more acceptable level of ris) !ith some form of ris) reduction activity. ondition based inspection (nspection intervals=due dates become more dependent on the equipment condistion. What is the RBI process capable of generating? 71.8 an)ing by relative ris) of all equipment evaluated. 72.8 detailed description of the inspection plan to be employed for each equipment item 7$.8 discription of any other ris) mitigation activites 76.8The e#pected ris) levels of all equipment after the inspection plan and other ris) mitigation activites have been implemented 7'.8 (dentification of ris) drivers. Whatt is RBI Wha RBI benef benefits its!! 7a8 an overall reduction in ris) for facilities and equipment assessed. 7b8 n acceptance=understanding of the current ris). What are R!B!I! limitations or things it will not compensate for? 718 (naccurate or missing information. 728 (nadequate design or faulty equipment instalation. 7$8 Operating outside the acceptable (DO 768 not effectively e#cuting the plans 7'8 ac) of sound engineering or operational judgment. What equipment is co"ered under this R# for RBI? 7a8 Pressure 4essels 7b8 Process piping 7c8 Ctorage tan)s 7d8 otation 9quipment ; pressure containg components 7e8 +oiler and heater; pressuri?ed components 7f8 @eat e#changers 7g8 pressure relief devices What equipment is not co"ered under the $#I %&' RBI? 7a8 instruments and system controls 7b8 electrical systems 7c8 structural system
7d8 machinery components 7e#cept pump and compressor castings. Who is the target audience for this Recommended #ractice (R!#!) %&' R!B!I! The inspection and engineering personnel !ho are responsible for the mechanical integrity and operability of equipment covered by this recommended practice. .%.%. .(. . (.%. %.h. h.9. 9. .. . .. .. .P. P. . . .C .C..(. .C . C./ ./.9 .9.. .C . C. ..T .T.. .C . C.T. T./ /. +..9 +. .9.4. .4.9 9. %.% %. %.P .P..C. %.O.F. 9.P.. F./ F. /.9 .9... *!$!+!,!# . (.O.D. (.C.O. ..O.P .P. ... /..O.%. / /..C.5. / ..% . .%.9 .9.. 59 5 9 FP O.C O .C.@ .@. ... P.@.. P./.(. P.O.F. P.C./. P.T..C.%.%. P.T.. C.%.%. P.4 P. 4. ..% .%.. A A =A% A... .+.(. .+. (. .% . %./. ../.P. C.(. C. (... T.9 T .9./ ./. ... T..O. B.T. B. T.
merican %hemistry %ouncil mer m eric ican an (n (nst stit itut ute e of of %he %hemi mica call 9ng 9ngin inee eers rs as lo lo! ! as as rea reaso sona nabl bly y pra pract ctic ical al me meri rica can n a ati tio onal Cta Ctan ndard rds s (n (nsti titu tutte me meri rica can n Coc Cocie iety ty of /e /ech chan anic ical al 9n 9ngi gine neer ers s mer m eric icam am Co Coci ciet ety y of of on onde dest stru ruct ctiv ive e Tes Testi ting ng me meri rica can n Co Cocie iety ty of Te Test /a /ate teri ria als boili bo iling ng liqu liquid id e#p e#pan andin ding g vapo vaporr e#plo e#plosio sion n %ente terr fo for %h %hemic ica al Pro Proc cess Cafe fetty consequence of failure 9nvironmental 9nvironme ntal Protection gency fail ilu ure modes an and eff effe ects analy lysi sis s ha?a ha ?ard rd an and d ope opera rabi bili lity ty as asse sess ssme ment nt integrity operating !indo! (nternational (nternat ional Organi?ati Organi?ation on for Ctand Ctandardi?ation ardi?ation lay la yers of pro rote tec cti tio on analysi sis s /anagement of change material selection diagrams ati a tion onal al ss ssoc ocia iati tion on of %o %orr rros osio ion n 9ng 9ngin inee eers rs nond no ndes estru tructi ctive ve e# e#ami amina natio tion n ationall Fire Protection ssociati ationa ssociation on Occu Oc cupa pati tion onal al Ca Cafe fety ty an and d @e @eal alth th d dmi mini nist stra rati tion on process ha?ards analysis positive material identifica identification tion probability of failure process safety management polythionic polythion ic acid stress corrosion crac)ing Pre ress ssu ure 4ess sse el e esearc rch h %o %ouncil quality assurance=quality control Auantitative ris) assessment ris);bas ris); based ed insp inspecti ection on reliability ce centered ma maintenance ris) management plan safet saf ety y int integ egrit rity y lev level el Tubu Tu bula larr 9# 9#ch chan ange gers rs /a /anu nufa fact ctur ures es s sso soci ciat atio ion n The etherlands Organi?ation for pplied Ccientific esearch ultr ul tras ason onic ic te test stin ing g
Absolute risk Absolute risk n ideal ideal and accurate accurate description description and quantific quantification ation of ris). ris). Acceptable risk level of ris) that is acceptab acceptable le to the o!ner;use o!ner;user. r. A.L.A.R.P.
as lo! as reasonably practical concept of minimi?ation that postulates that attributes 7such as ris)8 can only be reduced to a certain minimum under current technology and !ith reasonable cost. Compon Comp onen ents ts Parts that ma)e up a piece of equipment or equipment item. For e#ample a pressure boundary may consist of components 7pipe" elbo!s" nipples" heads" shells" no??les" stiffening rings" s)irts" supports" etc.8 that are bolted or !elded into assembles to ma)e up equipment items. Consequence n outcome outcome from an event. There There may be be one or or more consequenc consequences es from an event. event. %onsequen %onsequences ces may range from positive to negative. @o!ever" consequences are al!ays negative for safety aspects. %onsequences may be e#pressed qualitatively or quantitatively. Corrosion special specialist ist person !ho is )no!ledgea )no!ledgeable ble and e#perienc e#perienced ed in the specific specific process process chemistries" chemistries" corrosion corrosion degradation mechanisms" materials selection" corrosion mitigation methods" corrosion monitoring techniques" and their impact on pressure equipment. Cost-effective n activity that is both both effective effective in resolving resolving an issue issue 7e.g. some some form of of mitigation8 mitigation8 and is a financia financially lly sound use of resources. Damage (or deterioration mec!anism process that induces induces micro and=or and=or macro material changes changes over over time that that are harmful harmful to the material condition or mechanical properties. 5amage mechanisms are usually incremental" cumulative" and" in some instances" unrecoverable. %ommon damage mechanisms include corrosion" stress corrosion crac)ing" creep" erosion" fatigue" fracture" and thermal aging. Damage Dama ge (o (orr det deter erio iora rati tion on mod mode e The physical manifestation of damage 7e.g. !all thinning" pitting" crac)ing" rupture8. Damage to tolerance The amount of deterioration that a component can !ithstand !ithout failing. Design premise ssumptions ssumptio ns made during during the design 7e.g. 7e.g. design design life and corrosion allo!ance allo!ance needed8. needed8. Deterior Deter iorati ation on The reduction in the ability of a component to provide its intended purpose of containment of fluids. This can be caused by various damage mechanisms 7e.g. thinning" crac)ing" mechanical8. 5amage or degradation may be used in place of deterioration. "quipment n individual individual item that that is part of of a system. system. 9#amples 9#amples include pressure pressure vessels" vessels" relief devices" devices" piping" piping" boilers" and heaters. "vent Occurrence of a particular set of circumstances. The event may be certain or uncertain. The event can be singular or multiple. The probability of an event occurring !ithin a given period of time can be estimated. "vent tree
n analytical analytical tool that that organi?es organi?es and characteri?es characteri?es potential occurrence occurrences s in a logical logical and graphical graphical manner. The event tree begins !ith the identification of potential initiating events. Cubsequent possible events 7including activation of safety functions8 resulting from the initiating events are then displayed as the second level of the event tree. This process is continued to develop path!ays or scenarios from the initiating events to potential outcomes. "#ternal event 9vents resulting from forces of nature" acts of >od" sabotage" or events such as neighboring fires or e#plosions" terrorism" neighboring ha?ardous material releases" electrical po!er failures" forces of nature" and intrusions of e#ternal transportation vehicles" such as aircraft" ships" trains" truc)s" or automobiles. 9#ternal events are usually beyond the direct or indirect control of persons employed at or by the facility. $acilit% ny location location containing containing equipment equipment and=or and=or components components to be addressed addressed under under this P. P. $ailure Termination of the ability of a system" structure" equipment or component to perform its required function of containment of fluid 7i.e. loss of containment8. Failures may be unannounced and undetected at the instant of occurrence 7unannounced failure8. For e#ample" a slo! lea) under insulation may not be detected until a pool of fluid forms on the ground or someone notices a drip or !isp of vapor. small lea) may not be noticed until the ne#t inspection 7unannounced failure8" e.g. slo! lea)age from buried piping or small lea) in a heat e#changer tubeJ or they may be announced and detected by any number of methods at the instance of occurrence 7announced failure8" e.g. rupture of a pipe in a process plant or sudden decrease in pressure in the system. $ailure $ailu re mode mode The manner of failure. For +(" the failure of concern is loss of containment of pressuri?ed equipment items. 9#amples of failure modes are small hole" crac)" and rupture. $itness-$ $itnes s-$oror-&e &erv rvice ice as asse sess ssme ment nt methodology methodology !hereby !hereby damage damage or fla!s=imperfectio fla!s=imperfections ns contained contained !ithin a component component or equipment equipment item are assessed in order to determine acceptability for continued service. 'aard physical physical condition or a release release of a ha?ardous ha?ardous material that that could result result from component component failure failure and result in human injury or death" loss or damage" or environmental degradation. @a?ard is the source of harm. %omponents that areused to transport" store" or process a ha?ardous material can be a source of ha?ard. @uman error and e#ternal events may also create a ha?ard. 'aard and operabilit% stud% 'A)*P stud% @EOP study study is a form form of failure modes and and effects effects analysis 7F/98. 7F/98. @EOP @EOP studies" studies" !hich !ere !ere originally developed for the process industry" use systematic techniques to identify ha?ards and operability issues throughoutan entire facility. (t is particularly useful in identifying unforeseen ha?ards designed into facilities due to lac) of information" or introduced into e#isting facilities due to changes in process conditions or operating procedures. Thebasic objectives of the techniques are: +nspection ctivities performed performed to verify that materials" fabrication fabrication"" erection" erection" e#aminations" e#aminations" testing" testing" repairs" etc." conform to applicable code" engineering" and=or o!ner0s !ritten procedure requirements. (t includes the planning" implementation" and evaluation of the results of inspection activities. The e#ternal"
internal" or on;stream assessment 7or any combination of the three8 of the condition of pressure equipment. +ntegrit% operating window +*, 9stablished limits for process variables that can affect the integrity of the equipment if the process operation deviates from the established limits for a predetermined amount of time. anagement of of c!ange *C documented documented management management system for revie! revie! and approval of changes changes in process" process" equipment equipment or piping systems prior to implementation of the change. itigation imitation of any negative consequence or reduction in probability of a particular event. Probabilit% 9#tent to !hich an event is li)ely to occur !ithin the time frame under consideration. The mathematical definition of probability is Ka real number in the scale 3 to 1 attached to a random event.K Probability can be related to a long;run relative frequency of occurrence or to a degree of belief that an event !ill occur. For a high degree of belief" the probability is near one 718. Frequency rather than probability may be used in describing ris). 5egrees of belief about probability can be chosen as classes or ran)s li)e Krare=unli)ely=moderate=li)ely=almost certainK or Kincredible=improbable=remote=occasional=probable=frequent.K Process unit group of of systems arranged arranged in a specific specific fashion to produce a product or service. 9#ample 9#amples s of processes include po!er generation" acid production" fuel oil production" and ethylene production. ualitative risk anal%sis n analysis analysis that uses uses broad categori?ati categori?ations ons for probabilities probabilities and and consequence consequences s of failure. failure. /ethods that use primarily engineering judgment and e#perience as the basis for the determination of probabilities and consequences of failure. The results of qualitative ris) analyses are dependent on the bac)ground and e#pertise of the analysts and the objectives of the analysis. F/9 and @EOPs are e#amples of qualitative ris) analysis techniques that become A methods !hen consequence and failure probability values are estimated along !ith the respective descriptive input. Reassessment The process of integrating inspection data or other changes into the ris) analysis. Relati Rela tiv ve ris risk k The comparative ris) of a facility" process unit" system" equipment item or component to other facilities" process units"systems" equipment items" or components" respectively. Residual Resid ual risk risk The ris) remaining after ris) mitigation. Risk %ombination of the probability of an event and its consequence. (n some situations" ris) is a deviation from the e#pected. Dhen probability and consequence are e#pressed numerically" ris) is the product. Risk acceptance decision decision to accept accept a ris). is) is) acceptance acceptance depends depends on ris) ris) criteria.
Risk anal%sis Cystematic use of information to identify sources and to estimate the ris). is) analysis provides a basis for ris) evaluation" ris) mitigation and ris) acceptance. (nformation can include historical data" theoretical analysis" informed opinions" and concerns of sta)eholders. Risk assessment Overall process of ris) analysis and ris) evaluation. Risk avoidance 5ecision not to become involved in" or action to !ithdra! from a ris) situation. The decision may be ta)en based on the result of ris) evaluation. Risk-based Risk-bas ed inspe inspectio ction n R/+ ris) assessment assessment and manageme management nt process process that is focused focused on on loss of containmen containmentt of pressuri?ed pressuri?ed equipment in processing facilities" due to material deterioration. These ris)s are managed primarily through equipment inspection. Risk communication 9#change or sharing of information about ris) bet!een the decision ma)er and other sta)eholders. The information may relate to the e#istence" nature" form" probability" severity" acceptability" mitigation"" or other aspects of ris). mitigation Risk criteria Terms of reference by !hich the significance of ris) is assessed. is) criteria may include associated cost and benefits" legal and statutory requirements" socio;economic and environmental aspects" concerns of sta)eholders" priorities and other inputs to the assessment. Risk driver n item affecting affecting either either the probability" probability" conseque consequence" nce" or both both such that that it constitutes constitutes a significan significantt portion of the ris). Risk estimation Process used to assign values to the probability and consequence of a ris). is) estimation may consider cost" benefits" sta)eholder concerns" and other variables" as appropriate for ris) evaluation. Risk evaluation Process used to compare the estimated ris) against given ris) criteria to determine the significance of the ris). is) evaluation may be used to assist in the acceptance or mitigation decision. Rrisk Rris k ide ident ntif ific icat atio ion n Process to find" list" and characteri?e elements of ris). 9lements may include: source" event" consequence" probability. is) identification may also identify sta)eholder concerns. Risk ma management %oordinated activities to direct and control an organi?ation !ith regard to ris). is) management typically includes ris) assessment" ris) mitigation" ris) acceptance" and ris) communication. Risk mitigation Process of selection and implementation of measures to modify ris). The term ris) mitigation is sometimes used for measures themselves. Risk reduction
ctions ta)en ta)en to lessen lessen the probability probability"" negative consequ consequences" ences" or both both associated associated !ith !ith a particular particular ris). &emi-quantita &emi-qua ntitative tive ana anal%s l%sis is semi;quantitative semi;quantitative analysis analysis includes includes aspects aspects of both both qualitative qualitative and quantitat quantitative ive analyses. analyses. &ource Thing or activity !ith a potential for consequence. Cource in a safety conte#t is a ha?ard. &ta tak ke!ol old der ny individual" individual" group group or organi?ation organi?ation that that may affect" affect" be affected affected by" by" or perceive perceive itself to to be affected affected by the ris). &%stem collection collection of equipment equipment assembled assembled for for a specific function !ithin !ithin a process process unit. 9#amples 9#amples of of systems include service !ater system" distillation systems" and separation systems. 0urnaround period of of do!n time to perform inspectio inspection" n" maintenance" maintenance" or modification modifications s and prepare prepare process process equipment for the ne#t operating cycle. 0o#ic c!emical ny chemical chemical that presents presents a physical or health ha?ard ha?ard or an an environmental environmental ha?ard ha?ard according according to the appropriate material safety datasheet. These chemicals 7!hen ingested" inhaled" or absorbed through the s)in8 can cause damage to living tissue" impairment of the central nervous system" severe illness" or in e#treme cases" death. These chemicals may also result in adverse effects to the environment 7measured as ecoto#icity and related to persistence and bioaccumulation potential8. 1nmitigated risk The ris) prior to mitigation activities.
Dhat is the .+.(. process capable of >eneratingG 18 a ran)ing by relative ris) of all equipment evaluatedJ 28 a detailed description of the inspection plan $8 a description of any other ris) mitigation activities 68 the e#pected ris) levels of all equipment after the inspection plan and other ris) mitigation activities have been implementedJ '8 identification of ris) drivers. The primary !or) products of the +( assessment and management approach are plans that address !ays to manage ris)s on an equipment level. These equipment plans highlight ris)s from a safety=health=environment perspective and=or from an economic standpoint. +( plans should include cost;effective actions along !ith a projected ris) mitigation. (mpl (m plem emen enta tati tion on of th thes ese e pla plans ns pr prov ovid ides es on one e of of the the fo foll llo! o!in ing: g: a8an overall reduction in ris) for the facilities and equipment assessed" b8an acceptance=understanding of the current ris). 0able 230!ree Levels of P*$ Possible Aualitative an) nnual Failure Probability or Frequency o! L3.3331 /oderate 3.3331 to 3.31
@igh M3.31 0able 43&i# 43&i# Levels of P*$ P*$ Possible Aualitative an) nnual Failure Probability or Frequency emote L3.33331 4ery o! 3.33331 to 3.3331 o! 3.3331 to 3.331 /oderate 3.331 to 3.31 @igh 3.31 to 3.1 4ery @igh M3.1 ualitative P*$ Anal%sis qualitative qualitative method involves identificatio identification n of the units" systems systems or equipment" equipment" the the materials materials of construction and the corrosive components of the processes. On the basis of )no!ledge of the operating history" future inspection and maintenance plans and possible materials deterioration" POF can be assessed separately for each unit" system" equipment grouping or individual equipment item. 9ngineering judgment is the basis for this assessment. POF category can then be assigned for each unit" system" grouping or equipment item. 5epending on the methodology employed" the categories may be described !ith !ords 7such as high" medium" or lo!8 or may have numerical descriptors 7such as 3.1 to 3.31 times per year8. uantitative P*$ Anal%sis There are several approaches to a quantitative probability analysis. One e#ample is to ta)e a probabilistic approach !here specific failure data or e#pert solicitations are used to calculate a POF. nother approach approach is used !hen !hen inaccurate inaccurate or insufficient insufficient failure failure data e#ists on the the specific specific item of interest. (n this case" general industry" company or manufacturer failure data are used. methodology should be applied to assess the applicability of these general data. Identification of credible damage mechanisms and failure modes for equipment in a risk analysis is essential to blank and the blank of the risk analysis! 7a8 damage mechanisms 7b8 Auantitative ris) 7c8 Auality and and effectiveness effectiveness 7c8 Auality and and effectiveness effectiveness Risk presented in quantitati"e risk analysis as a 7a8 Precise numeric value 7b8 F orm of ris) /atri# 7c8 Form of event tree and Fault tree. 7a8 Precise numeric value
-amage mechanisms include corrosion. cracking. mechanical and metallurgical damage! /nde /n ders rsta tand ndin ing g da dama mage ge me mech chan anis isms ms is im impo port rtan antt fo for0 r0 a8 the analysis of the POFJ b8 the selection of appropriate inspection intervals=due dates" locations and techniquesJ c8 the ability to ma)e decisions 7e.g. modifications to process" materials selection" monitoring" etc.8 that can eliminate or reduce the probability of a specific damage mechanism. Failure modes identify how the damaged component will fail (e!g! by leakage or by rupture)! /nde /n ders rsta tand ndin ing g fai failu lure re mo mode des s is is im impo port rtan antt for for th thre ree e re reas ason ons0 s0 a8 the analysis of the %OF" b8 the ability to ma)e run;or;repair decisions" c8the selection of repair techniques
9conomic loss for consequences may be placed into categories that have pre;defined ranges:
12cessi"e inspections can ha"e what effect on risk le"el0 /ay cause the ris) level to increase RBI is focused on a systematic determination of What type risk? elative is) RBI is a substitute for? a8@EOP Ctudy b8 ns!er: ns!er: one
P@ c8/( Programs
d8one
Risk riteria is? Terms of reference by !hich the significance of ris) is assessed %an include associated costs and benefits" socio;economic and environmental aspects" legal and statutory reqs Implementation of RBI plans will? Provide an overall reduction in ris) for the facility and=or equipment Provide an acceptance=understanding of the current ris) (dentify equipment that does not require inspection or some other form of mitigation because of acceptable level of ris) The ultimate goal of inspection is? the safety and reliability of operating facilities $n equipment plan is? The !or) product of the +( assessment approach that address !ays to manage ris). $bsolute Risk is? n ideal and accurate accurate description description and quantificatio quantification n of ris) $ *a3ard is? physical physical condition condition or a release of a ha?ardous ha?ardous material material that that could result from from component component failure and result in human injury or death" loss or damage" or environmental degradation. @a?ard is the source of harm.
Probability # %onsequenceHis) Failure is? Termination of the ability of a system" structure" equipment or component to perform its required function of containment of fluid. ie loss of containment What is the industry scope of $#I R# %&'? @ydrocarbon and chemical process industry $#I R# %&' is intend to ? (dentify and clarify the essential elements of an +( analysis and program
$#I R# %&'4s primary audience is? (nspection and engineering personnel !ho are responsible for the mechanical integrity and operability of equipment covered by this P Risk management plans should be adjusted when? s ne! data becomes becomes available available or !hen changes changes occur occur B5161 +oiling liquid e#panding vapor e#plosion
+( requires the involvement of various segments of the organi?ation such as engineering" maintenance and operations 5oss of containment is generally e"aluated as? oss of fluid to the e#ternal environment RBI addresses an area of risk management not completely addresses in other risk management efforts such as? Process @a?ards nalyses 7P@8 (ntegrity Operating Dindo! 7(OD8 eliability %entered /aintenance 7%/8 RBI will not compensate for inaccurate or missing information" inadequate designs or faulty equipment installation" operating outside the acceptable (ODs" not effectively e#ecuting the plans" lac) of qualified personnel or team!or)" lac) of sound engineering or operational judgment. RBI as a continuous impro"ement tool pro"ides a "ehicle to? (mprove inspection of facilities and systematically reduce the ris) associated !ith pressure boundary failures $n 1"ent is? Occurrence of a particular set of circumstances #rimary work products of the RBI assessment are0 plans that address !ays to manage ris) -amage Tolerance is? The amount of deterioration that a component can !ithstand !ithout failing. 7itigation is? imitation of any negative consequence or reduction in probability of a particular event. 8takeholder ny individual" individual" group group or organi?a organi?ation tion that may affect" affect" be affected affected by" by" or perceive perceive itself to be affected by the ris).
7itigation action is an appropriate response to? Dhen the probability and consequence combination 7ris)8 is high enough to be unacceptable Risk is? The combination of the probability of some event occurring during a time period of interest and the consequences" 7generally negative8 associated !ith the event. Risk Reduction The act of mitigating a )no!n ris) that is deemed to be too high to a lo!er" more acceptable level of ris) !ith some form of ris) reduction activity 1ffecti"e risk based decision making can only take place when considering what? %OF < POF What is the I8,9Risk line representation representation on a constant constant ris) ris) level. Risk reduction is part of? is) management Inspection ,ptimi3ation point is is reached reached !here !here additional additional inspection inspection activity activity begins begins to sho! sho! a diminishing diminishing return and" eventually" may produce very little additional ris) reduction. (f e#cessive inspection is applied" the level of ris) may even go up With an initial in"estment in inspection acti"ities. risk generally is? significantly reduced. The use of e2pert opinion is included in risk assessments occurs when? (n most regardless of type or level :R$ Auantitative is) nalysis :R$ % tasks are Cystem (d @a?ards id Probability assessment %onsequence analysis is) esults 8emi quantitati"e $nalysis results are gi"en as? consequence and probability categories or as ris) numbers Fit for 8er"ice $ssessment methodology methodology !hereby !hereby damage damage or fla!s=impe fla!s=imperfections rfections contained contained !ithin !ithin a component component or equipment item are assessed in order to determine acceptability for continued service.
The results of a damage mechanisms and failure modes analysis for RBI should indicate0 1. list of credible damage mechanisms" credible damage modes and a ran)ing of credible failure modes 2. list of credible damage mechanisms" credible damage modes The purpose of establishing operational boundaries is to? identify )ey process parameters that may impact deterioration 8tart9up and shutdown conditions as well as emergency and non9routine conditions should also be re"iewed for? their potential effect on POF and %OF. The accuracy of results from a qualitati"e analysis is dependent on? The bac)ground and e#pertise of the ris) analysts and team members -amage mechanisms include0 %orrosion" crac)ing" mechanical and metallurgical damage. It is beneficial to the accuracy and quality of an RBI analysis to assure that the data is? Bp to date and validated by )no!ledgeable persons Risk9based inspection ris) assessment assessment and management management process process that that is focused focused on loss loss of containme containment nt of pressuri?ed equipment in processing facilities" due to material deterioration. These ris)s are managed primarily through equipment inspection. ,n #,F a probabilistic approach use what type of data to calculate #,F specific failure data or e#pert solicitations In most consequence e"aluations. a key element in determining the magnitude of the consequence is? the volume of fluid released. The total risk is The sum of the individual ris)s for each specific consequence. Flammable e"ents can cause damage in two ways0 thermal radiation and blast overpressure. The consequence analysis in an RBI program is performed to pro"ide discrimination bet!een equipment items on the basis of the significance of a potential failure. Risk reduction ctions ta)en to lessen the the probability" probability" negative negative conseque consequences" nces" or both associated associated !ith !ith a particular ris). -esign is critical for flammables. since the ;;;;;;;;;;;;; can enhance flame speed under some circumstances!
!ater curtain The inspector
