5. Introduction to Risk-Based Inspection Flashcards
- 1 Key Elements of an RBI Program
a) management systems for maintaining
documentation, personnel qualifications, data requirements
- 1 Key Elements of an RBI Program
b) documented method for
POF and COF determination
5.1 Key Elements of an RBI Program
C) All the elements outlined
in the Purpose section
5.2 One Objetive of RBI
Determine what incident could occur (consequence) in the event of an
equipment failure,
and how likely (probability) it is that the incident could happen
5.2 When the probability and consequence combination (risk) is high enough to be unacceptable
A mitigation action to reduce the
probability and/or the consequence of the event is appropriate.
5.2 The combination of probability and consequence produce
An effective
risk-based decision-making take place
5.2 Focus of Risk acceptability criteria
Not every failure will lead to an undesirable incident with serious consequence (e.g. water leaks) and
that some serious consequence incidents have very low probabilities (e.g. rupture of a clean propane vessel).
- 2 About Risk plot diagram
- Represent
the probability and COF
- 2 About Risk plot diagram
- Ordering of equipments by risk and produces a
risk-based ranking foccusing attention on the areas of highest risk
- 2 About ISO-risk line on Risk plot diagram
- Represents a
constant risk level
- 2 About ISO-risk line on Risk plot diagram
- Items that fall on or very near are
roughly equivalent in their level of risk.
- 2 About ISO-risk line on Risk plot diagram
- A user-defined acceptable risk level could be
plotted as an ISO-risk line
- 2 About ISO-risk line on Risk plot diagram
- Would separate the unacceptable from
the acceptable risk items
- 3 Variables for the selection of RBI assessment levels (1/2)
a) objective of
b) number of
c) available
d) assessment
a) the study,
b) facilities and equipment items
c) resources,
d) timeframe,
- 3 Variables for the selection of RBI assessment levels (2/2)
e) complexity of
f) nature and quality of
g) risk discrimination
e) facilities and processes,
f) of available data,
g) needed.
5.3.1 Ways of application of RBI procedure
Can be applied
qualitatively, quantitatively, or by using aspects of both (i.e. semi-quantitatively).
- 3.1 Approaches of RBI procedure
- Each approach provides a systematic way to screen for
risk, areas of potential concern, and develop a
prioritized list for more in-depth inspection or analysis.
- 3.1 Approaches of RBI procedure
- Each approach develops a risk ranking measure to be used for evaluating separately the
POF and the potential COF. These two values are then combined to estimate risk of failure.
- 3.1 Choosing the approaches of RBI procedure
- The chosen approach can be selected at
the beginning of the analysis process and carried through to completion
- 3.1 Choosing the approaches of RBI procedure
- may be changed (i.e. the analysis may become more or less quantitative) as
the analysis progresses
- 3.1 If the risk determined using any approach is below the acceptance criterion specified by the management of the organization conducting the analysis
- no further analysis, inspection, or mitigation steps are typically required and
the conditions and assumptions used in the analysis remain valid.
5.3.1 Continuum of RBI Approaches Diagram
Ver figura 3
- The spectrum of risk analysis should be considered to be a continuum with qualitative and quantitative approaches being the
two extremes of the continuum and everything in between being a semi-quantitative approach.
- 3.2 Concepts of RBI methodology
- Basis for prioritizing and managing the
efforts of an inspection program.
- 3.2 Concepts of RBI methodology
- The POF and COF are assessed separately and then
combined to determine risk of failure.
- 3.2 Concepts of RBI methodology
- Is based on relative risk rather than
a traditional risk analysis, but it uses similar techniques.
- 3.2 Risk and Risk mitigation plans
- Risk is compared and prioritized for
inspection planning and risk mitigation
- 3.2 Risk and Risk mitigation plans
- Risk mitigation plans may include inspection, changes in materials of construction, the
use of corrosion inhibitors, changes in operating conditions and fluids, etc.
- 3.2 An effective RBI program
- Identifies and measures the relative uncertainties associated with
ascertaining the condition of the equipment
- 3.2 An effective RBI program
- Uses risk to identify and prioritize when those uncertainties must be reduced, typically by
improved knowledge though additional data, likes degradation rate, other inspection, IOWs, probes, etc.
- 3.2 An RBI program includes the following
a) Systems or processes within
an operation prioritized by risk.
- 3.2 An RBI program includes the following
b) Determined risk value or category associated with
an equipment item
- 3.2 An RBI program includes the following
c) Prioritized equipment ranking based
on risk.
- 3.2 An RBI program includes the following
d) Development of an appropriate inspection program to
address key risk drivers.
- 3.3 Qualitative Approach Characteristics (1)
- Requires data inputs based on
engineering judgment, subject matter expertise, and experience.
- 3.3 Qualitative Approach Characteristics (1)
- Inputs are often given in
data ranges
- 3.3 Qualitative Approach Characteristics (1)
- Results are typically given in
qualitative terms such as high, medium, and low.
- 3.3 Qualitative Approach Characteristics (1)
- enables completion of a risk assessment in the
absence of detailed quantitative data
- 3.3 Qualitative Approach Characteristics (2)
- accuracy of results is dependent on the background and expertise of the
risk analysts and team members
- 3.3 Qualitative Approach Characteristics (2)
- is less precise than more
quantitative approaches
- 3.3 Qualitative Approach Characteristics (2)
- is effective in screening out
units and equipment with low risk
- 3.3 Qualitative Approach Characteristics (2)
- generally are not as repeatable as
quantitative assessments
5.3.4 Quantitative Approach
Advantages
- Are more systematic, consistent, and documented, and they are
easier to update than qualitative approach
5.3.4 Quantitative Approach
Advantages
- Generally uses a software program to calculate risk and
develop inspection program recommendations
5.3.4 Quantitative Approach
Advantages
- Outlines a methodology for prioritizing
equipment risk in a risk matrix or ISO-risk plot
5.3.4 Quantitative Approach
Advantages
- POF and COF are combined to
produce an estimate of risk for equipment
5.3.4 Quantitative Approach
Advantages
- Equipment items are ranked based on
risk with POF, COF, and risk calculated
5.3.5 Semi-quantitative Approach
Characteristics
- Has aspects derived from
both the qualitative and quantitative approaches.
5.3.5 Semi-quantitative Approach
Characteristics
- Obtain the major benefits of the
qualitative and quantitative approach
5.3.5 Semi-quantitative Approach
Characteristics
- Data used in a quantitative approach is needed for
this approach, but in less detail
5.3.5 Semi-quantitative Approach
Characteristics
- Models may not be
as rigorous
5.3.5 Semi-quantitative Approach
Characteristics
- Results are usually given in
consequence and probability categories or as risk numbers
5.3.6 Continuum of Approaches
Characteristics
- In practice, an RBI study typically uses aspects of
qualitative, quantitative, and semi-quantitative approaches
5.3.6 Continuum of Approaches
Characteristics
- The user is cautioned against drawing conclusions about different results when
different methodologies are used to evaluate the same piece of equipment.
5.3.6 Continuum of Approaches
Characteristics
- Risk-Based Inspection Planning Process diagram, identifies the essential elements of inspection planning based on risk analysis and is applicable to
Continuum of RBI Approaches diagram regardless of which RBI approach is applied
5.4 Precision vs Accuracy
Highlights
- Accuracy is a function of the
analysis methodology, the quality of the data, and consistency of application
5.4 Precision vs Accuracy
Highlights
- Precision is a function of the
selected metrics and computational methods.
5.4 Precision vs Accuracy
Highlights
- Risk presented as a precise numeric value (as in a quantitative analysis) implies a greater level of
accuracy when compared to a risk matrix (as in a qualitative analysis)
5.4 Precision vs Accuracy
Highlights
- It may be beneficial to use quantitative and qualitative methods in a
complementary fashion to produce the most effective and efficient assessment.
5.4 Precision vs Accuracy
Highlights
- The accuracy of any type of RBI analysis depends on
using a sound methodology, quality data, and qualified personnel
5.5 Understanding How RBI Can Help to Manage Operating Risks.
Factors of the operation for suitable condition of equipments
a) normal
b) upset
c) normal start-up and
d) idle or
e) emergency shutdown and
a) operation,
b) conditions,
c) shutdown,
d) out-of-service time,
e) subsequent start-up.
5.5 Understanding How RBI Can Help to Manage Operating Risks.
Process variables for each operating condition
a) process fluid, contaminants, and
b) pressures, including
c) temperatures, including
d) flow
e) desired unit run length between
a) aggressive components;
b) cyclic and transient conditions;
c) cyclic and transient conditions;
d) rates;
e) scheduled shutdowns (turnarounds).
5.5 Understanding How RBI Can Help to Manage Operating Risks.
Suitability of equipment in operation
- The suitability and current condition of the equipment within a
IOWSs will determine the POF
5.5 Understanding How RBI Can Help to Manage Operating Risks.
Suitability of equipment in operation
- The POF and associated COF will determine the
operating risk and therefore the need for mitigation.
5.5 Understanding How RBI Can Help to Manage Operating Risks.
Changes or new information for update a RBI
a) new data from
b) changes in operation, operating variables, or
c) changes in the
d) changes in process
e) equipment leaks or
a) inspection activities
b) operation outside of the IOWs;
c) process fluids;
d) equipment, including additions;
e) failures.
5.5 Understanding How RBI Can Help to Manage Operating Risks
Important points of RBI changes
- it is vital that any RBI process have
the ability to be easily updated
5.5 Understanding How RBI Can Help to Manage Operating Risks
Important points of RBI changes
- Changes or new information shall be
communicated on a timely basis
- 6 Management of Risks
- 6.1 Risk Management Through Inspection
- Inspection influences the
uncertainty of the risk associated
- 6 Management of Risks
- 6.1 Risk Management Through Inspection
- Inspection does not reduce
risk directly
- 6 Management of Risks
- 6.1 Risk Management Through Inspection
- The inspection may precipitates
risk mitigation activities that
change the POF
- 6 Management of Risks
- 6.1 Risk Management Through Inspection
Factors of POF due deterioration
a) deterioration
b) rate of
c) probability of
d) tolerance of the
a) type
b) deterioration;
c) identifying and predicting deterioration with inspection
d) equipment to the type of deterioration.
- 6 Management of Risks
- 6.2 Using RBI to Establish Inspection Plans and Priorities
- The primary product of an RBI effort should be an
inspection plan for each equipment item evaluated.
- 6 Management of Risks
- 6.2 Using RBI to Establish Inspection Plans and Priorities
- For risks considered to be unacceptable, the plan
should contain
the mitigation actions to reduce the level.
- 6 Management of Risks
- 6.2 Using RBI to Establish Inspection Plans and Priorities
- The level of the unmitigated risk should be used to
evaluate the urgency for performing the inspection
- 6 Management of Risks
- 6.3 Evaluation and Fitness-For-Service Analysis
- FFS is a
key part of RBI.
- 6 Management of Risks
- 6.3 Evaluation and Fitness-For-Service Analysis
- Risk without evaluation of results and assessment of equipment FFS after the inspection,
effective risk reduction may not be accomplished
- 6 Management of Risks
- 6.4 Other Risk Management
Where inspection may not be sufficient to
manage risks
a) equipment nearing end of
b) failure mechanisms such
c) consequence-dominated
a) service life;
b) as brittle fracture, fatigue
c) risks.
- 6 Management of Risks
- 6.4 Other Risk Management
Where inspection may not be sufficient to
manage risks
In such cases, non-inspection mitigation actions (such as equipment repair, replacement, etc) may be
the only way to reduce risk
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.1 General
- The RBI methodology is intended to complement other
risk-based and safety initiatives
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.1 General
- The output from several of safety initiatives can provide input to the RBI effort and RBI outputs may be
used to improve safety and risk-based initiatives already implemented by organizations
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.1 General
Examples of other safety initiatives
a) OSHA
b) EPA risk
c) American Chemistry
d) ASME risk
a) PSM programs,
b) management programs,
c) Council (ACC) responsible care,
d) assessment publications,
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.1 General
Examples of other safety initiatives
e) Center for Chemical
f) RCM and
g) PHA,
h) safeguarding
i) safety integrity
j) layers of protection analysis (LOPA).
e) Process Safety (CCPS) risk assessment techniques,
f) FMEA,
h) analysis,
i) level (SIL),
j) analysis (LOPA).
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.2 PHA (Process Hazard Analysis)
- A PHA uses a systemized approach to identify and
analyze hazards in a process unit.
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.2 PHA (Process Hazard Analysis)
- Hazards in the PHA of each equipment can be
specifically addressed in the RBI analysis.
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.2 PHA (Process Hazard Analysis)
- When PHA considers a hazard, it can increase the
POF, and RBI assessment could reflect the same.
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.2 PHA (Process Hazard Analysis)
- Some hazards identified affect the
consequence side of the risk equation
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.2 PHA (Process Hazard Analysis)
- Likewise, the results of an RBI assessment can significantly enhance the
overall value of a PHA.
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.3 PSM (Process Safety Management)
- PSM system can significantly reduce
risk levels in a process plant
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.3 PSM (Process Safety Management)
- PSM program can provide input for an
RBI study (i.e Extensive data on the equipment and the process)
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.3 PSM (Process Safety Management)
- RBI program can improve the mechanical integrity aspect of the
PSM resulting in a strengthened PSM program
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.4 Equipment Reliability
- Realibity program can provide input to the
probability analysis portion of an RBI program
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.4 Equipment Reliability
- Is important if leaks can be caused by
secondary failures, such as loss of utilities.
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.4 Equipment Reliability
- RCM/FMEA, can be linked with
RBI, resulting in an integrated program
- 7 Relationship Between RBI and Other Risk-Based and Safety Initiatives
- 7.4 Equipment Reliability
- RCM program can typically focus on the reliability of
other equipments that do not pertain to loss of containment but they are influential
- 8 Relationship with Jurisdictional Requirements
1. Codes and legal requirements vary from
one jurisdiction to another
- 8 Relationship with Jurisdictional Requirements
2. In some cases, jurisdictional requirements
mandate specific actions of inspections.
- 8 Relationship with Jurisdictional Requirements
3. All users shall review their jurisdictional code and
legal requirements for acceptability of using RBI
- 8 Relationship with Jurisdictional Requirements
4. RBI and Jurisdiction requirements can
work in a integrated mode.
5.8 Relationship with Jurisdictional Requirements
Benefits of applying RBI
a) evidence sound RBI can be used as a basis for
advocating adoption of RBI by jurisdictions;
5.8 Relationship with Jurisdictional Requirements
Benefits of applying RBI
b) evidence of fulfilling requirements of
meeting specific industry standards
5.8 Relationship with Jurisdictional Requirements
Benefits of applying RBI
c) basis for reducing risk further than
what may be achieved through time-based inspection rules