QUESTIONS ON API 580-581: RISK BASED INSPECTION
Select only one option which you think is most appropriate
Q.1 Successful implementation of RBI will give guidelines for: a) Appropriate inspection methods, extent of inspection and inspection intervals, b) Suggestions for Risk mitigation activities, c) Managing the residual level of risk after inspection and other mitigation actions have been implemented. d) All of above Q.2.
API 580 is specifically targeted at the application of RBI for: a] Hydrocarbon industries (Oil & Gas) b] Chemical process industries c] Power plants for Electric generation d] Only a and b above
Q.3.
The graphical representation of scenarios from initiation to potential outcome of an accident will be typically called as : a] Event tree b] Fault tree c] Risk tree d] Result tree
Q.4.
API 580 does not cover RBI assessment for: a] Process piping b] Storage tanks c] Structural systems d] Pressure relief devices
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Q.5.
The 3 approaches in RBI are typically called : a) Qualitative, Semi-Qualitative, Realistic b) Quantitative, Semi-Quantitative, Qualitative c) Realistic, Quantitative, Qualitative d) None of above
Q.6.
RBI methodology can be adopted for : a) Entire operating unit b) Section of operating unit c) Major system or major equipment d) All of above
Q.7.
Risk Management means: a) Risk mitigation only b) Risk mitigation and risk acceptance c) Risk mitigation, risk acceptance and risk communication d) Risk assessment, risk mitigation, risk acceptance, and risk communication.
Q.8.
The term “failure” used for Failure Analysis in RBI typically means: a) Failure due to human error b) Power failure c) Loss of containment d) All of above
Q.9. “Risk driver” in RBI means a) An item affecting probability significantly, b) An item affecting consequence significantly, c) An item affecting the either probability or consequence or both the significantly. d) A rash driver driving the plant vehicle who causes significant risk to plant personnel. 91
Q.10. In RBI analysis ‘ ALARP’ means: a) Always likely and reasonably possible b) As large as reasonably practical c) As large as reasonably profitable d) As low as reasonably practical Q.11. Qualitative risk analysis means a) A risk analysis based on Quality control plans of equipment b) A risk analysis that uses broad categorizations for probabilities and consequences of failure for purpose of risk ranking c) A risk analysis that uses NDT methods to evaluate risks d) A risk analysis that uses high quality data for detailed numerical analysis Q.12. RBI typically is focused on systematic determination of _______ for risk analysis and risk ranking a) Absolute risk b) Realistic risk c) Relative risk d) Residual risk Q.13. “ISO risk line” typically represents: a) Constant risk level b) Risk acceptable to international organization for standards c) Incident specific occurrence of risk level d) None of above Q.14 Risk Matrix and Risk Plot are typically used for: a) Risk Matrix for Quantitative and Risk Plot for Qualitative analysis b) Risk Matrix for Qualitative and Risk Plot for Quantitative analysis c) Both can be used for either Quantitative or Qualitative analysis 92
d) None of above are correct answers Q15. Quantitative analysis is less precise than quantitative analysis, but less costly and faster. If your objective is to carry out screening of low risks items/equipment, which type of analysis will you choose? a)
Qualitative
b)
Quantitative
c)
Quantitative first then Qualitative
d)
API 580 does not give any guideline
Q.16 Effective Inspection by itself can directly reduce risk. (a) True (b) Wrong
Q.17 For calculating Damage factor for thinning the term ‘age’ means: a)
Time since installation
b)
Time since RBI study was done
c)
Time since first inspection
d)
Time since last inspection
Q. 18 For finding out damage factor based on ‘inspection Effectiveness’, we should consider a)
All past inspections
b)
Only last inspection
c)
Only internal inspection
d)
Only external inspection
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Q.19. In consequence analysis in API RBI methodology a) Only Area-Based Consequence methodology is used b) Only Financial-Based Consequence methodology is used c) None of above these methodologies can be used d) Any of these methodologies can be used
Q.20. In Quantitative analysis the probability of failure depends on a) Generic failure frequency only, b) Damage factor and generic failure frequency, c) Management systems factor, and generic failure frequency d) Generic failure frequency , damage factor and management systems factor Q.21 Choose correct option a) The inspection methods will provide little information to correctly identify the true damage state (or 20–40% confidence) is ‘Poorly Effective’. b) The inspection methods that will correctly identify the true damage state in nearly every case (or 80–100% confidence) is ‘Highly Effective’. c) The inspection methods will correctly identify the true damage state about half of the time (or 40–60% confidence) is ‘Fairly Effective’. d) All of above are correct statements Q.22 In an API RBI assessment, which components should be checked for thinning. a) All components should be checked for thinning b) 50% components should be checked for thinning c) Only the components with General corrosion should be checked for thinning d) Only the components with Localised corrosion should be checked for thinning Q.23 If a piping circuit contains an injection point, then an adjustment factor equal to ------ should be used . If a highly effective inspection for injection point circuit (according to API 570) is performed, then this adjustment factor is D.
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a) 3,
2
b) 2,
0
c) 3,
1
d) 2,
1
Q.24 A vessel is in service since year 2003. It is undergoing General corrosion. Up to now, two inspections with external 30% scanning by manual UT were done, and one internal inspection with 60% examination of the surface (partial internals removed) accompanied by thickness measurements was done. There is no On-Line Monitoring. The value of Art parameter is 0.20. What is the Damage Factor? a) 4 b) 1 c) 10 d) 5 Q.25 For above vessel if corrosion was localized instead of general. Two inspections with 30% manual UT scanning, and spot thickness measurements at areas specified by a corrosion specialist were done. Also one internal inspection with 60% visual examination and spot UT measurements was done. There is no On-Line Monitoring. The value of Art parameter is 0.20. What is the Damage Factor? a) 10 b) 70 c) 35 d) 3 Q2.6 A vessel is in service since year 2003. It is undergoing Chloride stress corrosion cracking. Choose the correct answer. a) External Spot Radiography and Spot shear wave ultrasonics is ‘Usually Effective inspection b) Wet fluorescent magnetic particle testing of 100% weldments done from inside is ‘Highly Effective inspection’ . c) Visual inspection done from inside is ‘Fairly Effective inspection’ . d) None of above are correct answers
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Q.27 In Chloride SCC, if cracking is known to be present then for calculating damage factor Severity Index to be used is: a) 1 b) 50 c) 500 d) 5000 Q. 28 A Carbon steel insulated vessel is operating in marine weather . Temperature=160 deg. F. The Insulation is Fiberglass. Considering the vessel nozzles, the complexity is can be determined as ‘above average’ and the insulation condition is ‘average’ What corrosion rate is to be used for Damage Factor calculation? a) 15.6mpy b) 12.5mpy c) 19.5mpy d) 10 mpy Q. 29 As per API 581, Financial-Based Consequence of $ 200,000 is categorized as category ------- in consequence catagories: a) A b) B c) C d) D Q. 30 As per API 581, affected Area of 1600 sq. meters is categorized as category ------ in Area-Based Consequencec. a) B b) C c) D d) E Q.31. Logic models Event Tree and Fault tree are extensively used in : a)
Qualitative Analysis
b)
Quantitative Analysis
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c)
Used in both a and b
d)
Used in neither a or b
Q.32. “Fault Tree” represents a logical model showing a) Initiation of an event and its consequences b) Various ways which lead to the occurrence of event c) Faults in Design and Construction of equipment d) Faulty in operation and maintenance of the equipment Q.33. Typical parameters used for assessing environmental damage are: a)
Acres of land affected per year
b)
Miles of shoreline affected per year
c)
Number of human-use resources affected
d)
All of above
Q.34. Determining representative fluid and selecting a set of hole sizes is essential step in: a)
Qualitative approach only
b)
Quantitative approach only
c)
Essential for both
d)
Essential for none
Q.35. In RBI consequence analysis all releases are modeled in two types, namely : a)
Instantaneous release and continuous release
b)
Continuous release and intermittent release
c)
Intermittent release and Instantaneous release
d)
“Puff” release and Instantaneous release
Q.36. In RBI consequence analysis, if fluid inside the vessel is liquid but its boiling point is less than ambient temperature , the phase considered for consequence analysis will be taken as :
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a)
Solid
b)
Liquid
c)
Gas
d)
Liquid – Gas mixture
Q. 37 Probability of leak of a flammable fluid is 0.002, probability that it will catch fire is 0.5. What is probability of fire ? ( There is no solation/detection system) a)
50%
b)
0.0001
c)
0.001
d)
2%
Q.38 Which of the following would most unlikely result in Metallurgical deterioration a)
HTHA
b)
Fatigue
c)
CUI
d)
Chloride SCC
Q.39 Since RBI is a proven and sound risk management principle; it does not matter if designs/installations are faulty a) True b) False c) Cannot say
Q. 40 Engineering judgement and experience of the analyst are most required for which type of RBI assessment a) Quantitative b) Qualitative c) Semi-quantitative d) All of above
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Q.41 In POF calculations Generic Failure Frequency needs to be adjusted by using an adjustment factor which depends on the damage mechanisms that are active in a component and the type of inspection performed. This factor is called a)
Inspection factor
b)
Component factor
c)
Safety factor
d)
Damage factor
Q.42 Identify Correct Statement a) Properly implemented and correctly monitored RBI generally will result in Zero Risk b) Properly implemented RBI will generally leave “Residual Risk “ c) Properly implemented RBI will give guidance on inspection plan and inspection intervals. d) b) and c) above are correct statements Q.43 Mass of fluid available for release in a pressure vessel consists of a) Mass of fluid in pressure vessel b) Mass of fluid in pressure vessel + additional mass added in 3 minutes as limited to a 203 mm [8 in.] release hole size. c) Inventory Group Mass d) Lower of b) and c) Q.44. Consequence of toxic release area should take into account: a)
Area for the personnel injury
b)
Area for component damage
c)
Total of Both a) and b)
d)
Lower of a) and b)
Q.45. Integrity operating window is:
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a) Window provided in the plant wall for operating Process valves b) Limits for process variables which if changed beyond limits, will affect integrity of equipment c) Imaginary boundary enclosing equipment that is subject to same damage mechanisms d) None of above Q.46 Release hole size for rupture for consequence analysis for a 30” dia pressure vessel Is a) 4”, b) 30”, c) 16 “, d) 10” Q.47 In RBI, Sonic and subsonic release is applicable for: a) Liquid Release only b) Vapor Release only c) For both type Releases d) For None of above releases Q.48 In RBI API 581 Quantitative analysis, Consequences for which of the following are considered a) Flammable Consequences b) Toxic Consequences c) Non-Flammable Non-Toxic Consequences d) All of above Q.49 The parameter Art and Severity index SVI determine the damage factors. Choose correct choice from following. a) Parameter Art is used for thinning and Severity index SVI for cracking b) parameter Art and Severity index SVI both are used for cracking c) parameter Art and Severity index SVI both are used for thinning d) Parameter Art is used for cracking and Severity index SVI for thinning 100
Q. 50 The lowest temperature at which a fluid mixture can ignite without a source of ignition is called a) Auto-Ignition Temperature b) Ignition Temperature c) Flash-point Temperature d) Dew-point Temperature
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API 580-581: RISK BASED INSPECTION Answer Key Q. No.
Answer
Q. No.
Answer
Q. No.
Answer
1
d
21
d
41
d
2
d
22
a
42
d
3
a
23
c
43
d
4
c
24
b
44
a
5
b
25
c
45
b
6
d
26
d
46
c
7
c
27
d
47
b
8
c
28
a
48
d
9
c
29
c
49
a
10
d
30
d
50
a
11
b
31
b
12
c
32
a
13
a
33
d
14
b
34
b
15
a
35
a
16
b
36
c
17
d
37
c
18
a
38
a
19
d
39
b
20
d
40
b
102
