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