risk management techniques - web viewrisk management identifies hazards and tracks them through a...

Risk Management Techniques RPN, Force Field Analysis, Reliability Risk

Risk is the chance that an undesirable event might occur in the future that will result in some negative consequences. In the sense of the definition just given, risk is a part of everyday life. We all are faced with uncertainties in our lives, our careers, and our decisions. Since we cannot avoid such uncertainties, we must find ways to deal with them.

ANURAG RAYCHAUDHURY(2011E14) 1/1/2012

[RISK MANAGEMENT TECHNIQUES]

Table of Contents1.0 Risk:.................................................................................................................................................3

1.1 Risk Management:...........................................................................................................................3

1.2 Reliability Risk:.............................................................................................................................4

1.3 Analytical Reliability Tools...............................................................................................................4

1.3.1 FMEA........................................................................................................................................4

1.3.2. FTA...........................................................................................................................................5

1.3.3. RCA..........................................................................................................................................5

1.3.4. Worst-Case Analysis.................................................................................................................6

1.3.5. SCA...........................................................................................................................................7

1.4 Reliability Testing.............................................................................................................................8

1.4.1. Reliability growth testing:........................................................................................................8

1.4.2. Life testing...............................................................................................................................8

1.4.3. Validation testing.....................................................................................................................9

1.4.4. Production Reliability Testing................................................................................................10

1.4.5. Reliability Predictions and Assessments................................................................................10

1.5 Point estimates versus confidence intervals..................................................................................10

1.6. Conclusions...................................................................................................................................12

2.0 Risk Priority Number (RPN)............................................................................................................13

2.1 Risk Priority Number (RPN)............................................................................................................13

2.1.1. Severity (S).............................................................................................................................13

2.1.2. Occurrence (O).......................................................................................................................14

2.1.3. Detection (D).........................................................................................................................14

2.2. Assessing Risk...............................................................................................................................16

2.3 Revised RPNs and Percent Reduction in RPN:................................................................................18

2.4 Risk Ranking Tables........................................................................................................................19

2.5 Conclusion.....................................................................................................................................20

3.0 Force Field Analysis........................................................................................................................21

3.1 BRAINSTORMING RULES................................................................................................................22

3.2 Advantages of force-field analysis.................................................................................................24

3.2.1 Example..................................................................................................................................24

4.0 Bibliography:..................................................................................................................................25

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1.0 Risk:Risk can be defined as-

1. Possibility of suffering harm or loss: Danger.2. A factor, course, or element involving uncertain danger: Hazard.3. The danger or probability of loss to an insurer.4. The amount that an insurance company stands to lose.5. One considered with respect to the possibility of loss to an insurer

Risk is the chance that an undesirable event might occur in the future that will result in some negative consequences.

This latter definition of risk is often expressed as an equation:

Risk Severity = Probability of Occurrence x Potential Negative Impact

In the sense of the definition just given, risk is a part of everyday life. We all are faced with uncertainties in our lives, our careers, and our decisions. Since we cannot avoid such uncertainties, we must find ways to deal with them.

1.1 Risk Management:

Risk Management identifies hazards and tracks them through a sequence of events that creates a hazardous situation. This hazardous situation could result in harm to people, property, or the environment. The resulting harm has a severity and a probability of occurrence. The combination of severity and probability establishes the risk. Figure 1 illustrates the approach.

Risk management consists of the following activities:

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Identify concerns. Identify risks and risk owners. Evaluate the risks as to likelihood and consequences. Assess the options for accommodating the risks. Prioritize the risk management efforts. Develop risk management plans. Authorize the implementation of the risk management plans. Track the risk management efforts and manage accordingly.

1.2 Reliability Risk:

Reliability program is needed as part of an effective risk management program. Various tools of reliability can be used to help identify, prioritize, and manage risk.

1.3 Analytical Reliability Tools.

These include the Failure Modes and Effects Analysis (FMEA), Fault Tree Analysis (FTA), Root Cause Analysis (RCA), Worst Case Analysis, and Sneak Circuit Analysis (SCA).

1.3.1 FMEA The FMEA is an analytical tool used throughout the design process. It can be used to examine increasing levels of indenture, usually starting at the assembly level and progressing up. Briefly, the analysis is conducted to identify:

a. The various functions of the item being analyzed.b. The possible ways that the item could fail to perform each of its functions (failure

modes).c. The likelihood of each failure mode occurring.d. The effect, should the failure mode occur, on the item and system operation.e. The root cause of each failure mode.f. The relative priority of each failure mode.g. Recommended actions to reduce the likelihood, effect, or both of the failure modes,

beginning first with the highest priority modes.

Different standards are available that define the FMEA process. Although they may differ in the details, they all include similar steps. One of these is some way of prioritizing failure modes. The old military standard (MIL-STD-1629) describes a Failure Modes, Effects, and Criticality Analysis (FMECA) in which failure modes are prioritized based on their relative criticality, a function of the probability of occurrence and severity of effect. The Automobile Industry Action Group (AIAG) standard uses a risk priority number, also based on

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probability of occurrence, severity of effect, and other factors.

Whether the FMEA process described in the AIAG standard, the FMECA process described in MIL-STD-1629, or the process as documented in other standards is used, they share the common element of prioritizing risk. As such, the FMEA/FMECA process is an excellent tool for identifying technical risk. By tracking recommended actions for high-risk failure modes, and ensuring that the recommended design (or other) changes are effective, the technical risk can be managed.

1.3.2. FTAWhereas the focus of the FMEA is on a subassembly, an assembly, and so forth, the FTA focuses on a specific event, usually and undesired event (i.e., a failure). By creating what are known as fault trees, one can then trace all of the possible events or combinations of events that could lead to the undesired event.

Not only can the FTA directly contribute to identifying design risks, but it can also reduce risk during operation. By its very nature, the FTA can help in developing the diagnostics so necessary to the maintenance of a system. (The FMEA can also contribute to the development of diagnostics).

1.3.3. RCA

Given the limited funds and schedule facing each program manager, it is critical that item and money is not expended ineffectively. When high-risk failures occur during testing, design changes usually are required to reduce the risk to an acceptable level. This reduction is achieved by eliminating a failure mode, reducing the frequency with which the mode will occur, minimizing the effect of the mode, or some combination of these alternatives.

To arrive at an effective design change, the underlying cause of each failure must be determined. This underlying cause is not the failure mode. A failure mode, such as an open in a resistor, can be compared to a symptom. When we are ill, our doctor (we hope) does not treat our symptoms. Instead, the doctor tries to determine the underlying reasons for our illness. To do so requires experience, good judgment, and the use of diagnostic tools, such as X-ray, blood tests, and so forth.

Just as doctors search for the underlying cause of an illness, engineers must determine the underlying reason for a failure mode. These reasons are often referred to as failure mechanisms. They are the physics of failure. A primary tool used to identify these failure mechanisms is Root Cause Analysis (RCA). RCA is experience, judgment, and specific activities applied in combination. The activities include non-destructive and destructive

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inspections. Table 2 lists just a few of these activities conducted for RCA.

Table 2. Typical Activities for Determining Root Cause

Physical examination of failed item Fracture mechanics Nondestructive evaluation

o X-rayo Thermographyo Magnetic fluxo Penetrant dyeo Computerized tomographyo Ultrasonics

Mechanical testing Macroscopic examination

and analysis Microscopic examination

and analysis Comparison of failed

items with non-failed items

Chemical analysis Finite element analysis

1.3.4. Worst-Case Analysis

As part of the reliability and design programs, analysis can be performed in worst case conditions to assure adherence to the specification requirements, reducing the risk of failure due to inadequate operating margins.

The design is examined to identify circuit tolerance to parameter drift of critical parts that may lead to out-of-specification conditions over the system's operating life.

The analysis demonstrates sufficient operating margins for the operating conditions of the circuits, taking into consideration:

Parts parameter variations Initial tolerances Temperature Aging effects Radiation effects Power input line voltage variations Operational mode effects Circuit parameter variations due to loading & stimulus

1.3.5. SCA

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Many system failures are not caused by part failure. Design oversights can create conditions under which a system either does not perform an intended function or initiates an undesired function. Such events in modern weapon systems can result in hazardous and even dire consequences. A missile, for example, may be launched inadvertently because of an undetected design error.

A significant cause of such unintended events is the "sneak circuit." This is an unexpected path or logic flow that, under certain conditions, can produce an undesired result. The sneak path may lie in the hardware or software, in operator actions, or in some combination of these elements. Even though there is no "malfunction condition," i.e., all parts are operating within design specifications, an undesired effect occurs. Four categories of sneak circuits are listed in Table 3.

Table 3. Categories of Sneak CircuitsCategory Characteristics

Sneak Paths Unexpected paths along which current, energy, or logical sequence flows in an unintended direction.

Sneak Timing

Events occurring in an unexpected or conflicting sequence.

Sneak Indications

Ambiguous or false displays of system operating indications conditions that may cause the system or an operator to take an undesired action.

Sneak Labels

Incorrect or imprecise labeling of system functions - e.g., system inputs, controls, displays buses - that may cause an operator to apply an incorrect stimulus to the system.

Sneak circuit analysis is a generic term for a group of analytical techniques employed to methodically identify sneak circuits in hardware and software systems. Sneak circuit analysis procedures include Sneak Path Analysis, Digital Sneak Circuit Analysis, and Software Sneak Path Analysis.

1.4 Reliability Testing.

1.4.1. Reliability growth testing: The term Reliability Growth Testing (RGT) usually refers to a process by which the following three objectives are achieved:

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Failures are identified and analyzed.

The design is improved to eliminate the failures, reduce the probability of their occurrence, reduce the effects of the failures, or some combination of these alternatives.

The progress being made in the growth process is tracked with quantitative estimates of the reliability. Models, such as the Duane and AMSAA, are used for making the estimates.

When all three of these objectives are being pursued, the RGT is a formal program for achieving growth. Growth can also be achieved by analyzing the failures from any and all testing and developing design changes to address the failures. However, quantitative estimates of reliability may not be able to be made due to statistical limitations of combining data from different tests. For our purposes, we will refer to this latter process as Test-Analyze-And-Fix (TAAF).

Whether RGT or TAAF is used, the process of identifying and addressing failures helps reduce technical risk. The RGT also provides a quantitative means of assessing the risk of not meeting a specific reliability goal within budget and schedule.

1.4.2. Life testing

Every product and system consists of hundreds, perhaps thousands, or hundreds of thousands of parts. The system reliability depends on how these parts are connected together, how they are applied, and the reliability of each. Some parts may have little impact on system reliability due to their application. Others may be critical to the continued and safe operation of the system.

It is obvious that selecting the "right" parts is important. A "right" part is one that:

Performs the correct function Has sufficient reliability Meets other criteria such as support, obsolescence, and cost

Determining whether a part has the requisite reliability for a given application is an element of part characterization. Life testing is one method for characterizing a part from a reliability perspective. By testing a sample of parts, recording the times to failure for the parts, and analyzing these times to failure, the reliability of the population represented by the sample can be estimated2. As importantly, some insight into the category of failure (wearout, infant mortality, random failure3) can be gained. One common technique for analyzing the times-to-failure data is Weibull analysis (Reference 10).

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Using life testing, engineers can determine if the reliability of each part is adequate4 and, if not, what changes might be necessary to attain the required level. By ensuring that the "right" parts are selected, technical risk is reduced.

1.4.3. Validation testing

Validation testing helps confirm whether the efforts during design have paid off or not. It can be done at the part level or at higher level of indenture. The types of test often used for validation are listed in Table 4.

Table 4. Commonly Used Tests for ValidationLevel of Indenture

Parts Assembly and Higher· Weibull testing· Attribute testing

· Sequential testing· Fixed length testing· Attribute testing

RGT, TAAF, and part characterization is done as part of the design process, a process in which the design is changing. There is no pass-fail criterion for such tests; the objective is to identify and address weaknesses in the design from a reliability perspective. Validation testing, on the other hand, is ideally done on the "finished" design and is a "go-no-go" or "pass-fail" test. Validation testing provides the best measure of the level of reliability achieved before a full production decision is made.

When validation tests are included as part of the contractual requirements, it provides an added incentive to contractor and government alike to do the requisite engineering starting early in the program. Neither the customer nor the contractor wants the system to fail the validation test. Knowing that the test is a hurdle that must be passed provides incentive to control technical risk throughout the design process.

1.4.4. Production Reliability Testing

After the design is accepted, validation tests have been passed, and the production processes have been brought under control, Production Reliability Testing (PRT) may be conducted, especially when the production takes place over an extended period of time.

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PRT is intended to detect any degradation in reliability performance that may result from changes in suppliers, design processes, configuration, and so forth. When degradation is detected, PRT provides an early warning so that corrective actions can be considered before a large number of systems are delivered to the customer. Many of the same techniques used for validation purposes can be used for PRT. Thus, PRT helps reduce the risk of sending systems with poor reliability to the customer. In addition, the earlier that problems are detected, the lower the cost to correct the problems.

1.4.5. Reliability Predictions and Assessments

Realistic and fact based assessment of the level of reliability being achieved at any point in time is an important element of a comprehensive reliability program. The need for quantitative measures has been alluded to several times in this article (likelihood of a failure mode, reducing the probability of occurrence of a failure, and tracking growth in a formal RGT program).

The author distinguishes between a prediction and an assessment in the following way. A prediction is usually thought of as the quantitative output of a model, such as a parts count model, reliability block diagram, or simulation. An assessment is an overall evaluation of the reliability based on the output of models, test results, engineering judgment, and consideration of any assumptions and the limitations of the models and testing. The subject is much too broad and involved to cover here in detail. Two points, however, are important to the subject of risk management.

1.5 Point estimates versus confidence intervals

Predictions based on models and testing can always be expressed as a single, or point value. The output of some types of models, empirical models for example, can only be stated as point values. Point estimates are probably the most common way that technical people communicate predictions and assessments to management.

The problem with a point estimate is that it incorrectly conveys certainty. When one states that the MTTF of a part is 10,000 fatigue cycles or that the MTBF of a subsystem is 2,200 operating hours, it is often interpreted in the same way as stating that the part is 3.5 cm long or the subsystem weighs 450 pounds. The latter two measures are deterministic and, within the limits of our measurement equipment and changes in temperature and humidity, do not vary from day to day.

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Reliability, however, is a probabilistic concept. Reliability testing consists of testing samples. Even when several samples are taken from a population with a given distribution with known parameters, the parameters obtained from the sample testing vary in value. Given that the distribution of the population is never known, the variation in results from testing different samples can be very large. Thus, in accepting a point estimate as "gospel," we run the risk of being optimistic. Worse yet, we have no idea what the level of risk may be.

For those cases where a statistical model or test is used, we can provide confidence bounds on the point estimate. A confidence bound can be either one-sided (i.e., we are X% confident that the interval from the lower bound to infinity includes the true reliability) or two-sided (i.e., we are X% confident that the interval from a lower bound to an upper bound includes the true value of reliability). Consider the following statements concerning an item for which the MTBF requirement is 950 hours.

a. The estimate of reliability is 1,000 hours MTBF.b. The 90% confidence interval for reliability is 700 to 1,500 hours MTBF.

Which does a better job of indicating that the estimate is inexact and carries with it a risk of being wrong (i.e., the achieved MTBF is less than the requirement)? If the manager desires a smaller interval, he or she must either be willing to invest in additional testing or accept a higher risk of being wrong.

The Reliability Case: The Reliability Case is an example of an assessment. It is a progressively expanding body of evidence that a reliability requirement is being met. Starting with the initial statement of the requirements, the "Reliability Case" subsequently includes identified, perceived, and actual risks; strategies; and an Evidence Framework referring to associated and supporting information. This information includes evidence and data from design activities and in-service and field data as appropriate.

The Reliability Case provides an audit trail of the engineering considerations starting with the requirements and continuing through to evidence of compliance. It provides traceability of why certain activities have been undertaken and how they can be judged as successful. It is initiated at the concept stage, and is revised progressively throughout the system life cycle. Typically it is summarized in Reliability Case Reports at predefined milestones. Often, it is expanded to included maintainability (The R&M Case). The Reliability Case is developed using:

Calculations Analyses Testing

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Expert opinion Simulation Information from any previous use

Each Reliability Case report lists and cross references the parent requirements in the Evidence Framework, against which the evidence is to be judged, and is traceable to the original purchaser's requirement. The body of evidence traces the history of reviews and updates of the reliability design philosophy, targets, strategy and plan, which keep these in line with the changing status of the original risks and any new or emerging risks. The status of assumptions, evidence, arguments, claims, and residual risks is then summarized and discussed. Clearly, the Reliability Case can be an important part of the overall technical risk management effort.

1.6. Conclusions

Risk is always with us; there is no escaping it. However, we can deal with risk and keep it at an acceptable level by managing it. We can manage risk by using a variety of tools to:

1. Identify risks2. Evaluate them as to likelihood and consequences3. Assess the options for accommodating the risks4. Prioritize the risk management efforts5. Develop risk management plans6. Track and manage the risk management efforts

One of the tools available to the manager for specifically addressing technical risk is an effective reliability program. Many of the activities conducted to develop a system having the requisite level of reliability can directly contribute to the management of technical risk. These include:

1. Analyses2. Tests3. Predictions and Assessments4. The Reliability Case

By implementing reliability as part of a systems engineering approach, the results of reliability-focused activities can contribute to the many other activities that take place in a system acquisition program. The systems engineering approach capitalizes on the synergy of coordinated and synchronized technical activities. By eliminating duplicative effort and making maximum use of the results of activities, the systems engineering approach by its very nature helps minimize risk. Reliability, implemented as part of the systems engineering approach, can play a significant role in risk management.

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2.0 Risk Priority Number (RPN)

The Risk Priority Number (RPN) methodology is a technique for analyzing the risk associated with potential problems identified during a Failure Mode and Effects Analysis (FMEA).

2.1 Risk Priority Number (RPN)

It is a measure used when assessing risk to help identify critical failure modes associated with your design or process. The RPN values range from 1 (absolute best) to 1000 (absolute worst). The RPN is commonly used in the automotive industry.

Each failure (mode) has an assigned severity, occurence, and detectability values.

2.1.1. Severity (S)

Severity is a numerical subjective estimate of how severe the customer or end user will perceive the EFFECT of a failure.

2.1.2. Occurrence (O)

Occurrence or sometimes termed LIKELIHOOD is a numerical subjective estimate of the LIKELIHOOD that the cause, if it occurs, will produce the failure mode and its particular effect.

2.1.3. Detection (D)

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Detection is sometimes termed EFFECTIVENESS. It is a numerical subjective estimate of the effectiveness of the controls to prevent or detect the cause or failure mode before the failure reaches the customer. The assumption is that the cause has occurred.

After the ratings have been assigned, the RPN for each issue is calculated by multiplying Severity x Occurrence x Detection.

RPN= Severity * Occurrence * Detection

For example, with S = 5, O = 3, D = 6, the RPN is90 = (5)(3)(6).

The RPN value for each potential problem can then be used to compare the issues identified within the analysis. Typically, if the RPN falls within a pre-determined range, corrective action may be recommended or required to reduce the risk (i.e. to reduce the likelihood of occurrence, increase the likelihood of prior detection or, if possible, reduce the severity of the failure effect). When using this risk assessment technique, it is important to remember that RPN ratings are relative to a particular analysis (performed with a common set of rating scales and an analysis team that strives to make consistent rating assignments for all issues identified within the analysis). Therefore, an RPN in one analysis is comparable to other RPNs in the same analysis but it may not be comparable to RPNs in another analysis.

The RPN is not a measure of risk, but of risk priority. You would apply your limited resources to the most important problems. The RPN gives you a model to allocate these resources. Higher numbers are higher priority, so you should work on an RPN of 900, before you put resources on an RPN of 30.Some numbers cannot be an RPN. Many people have the mistaken belief that any number from 1 to 1,000 can be an RPN. Some values can’t occur (17, 22, and 925) as RPN.17 cannot be an RPN because it is a prime number larger than 10. You cannot multiply 3 numbers from 1 to 10 and get 17.

In contrast, many numbers can occur in multiple ways, the highly composite numbers. Consider120. There are 24 different ways it can become an RPN. Two examples are (S)(O)(D) =(2)(6)(10) = (8)(5)(3). In the first case the severity is near the bottom of the scale, 2, while in the second case, the severity is near the top of the scale, 8.There are long stretches of numbers that can’t be an RPN. For example, no number from 901 to 999 is an RPN.In the three dimensional RPN case there are 1,000 cells, but only 120 values.

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Figure 1: RPN maps 1000 problem descriptions onto 120 values

To see the artificiality of these groupings consider the group having an RPN score of 360. On a scale of 1 to 1000, 360 does not sound like a very high score. However, consideration of Figure 1 will show that 862 of the 1000 problem descriptions will have a smaller RPN score. Using the criteria given in the auto industry FMEA Manual, Figure 2 lists the 15 problems that outrank 86% of the other possible problems.

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2.2. Assessing Risk

Some words of caution when using the RPN value to assess risk - RPNs have no value or meaning in themselves. Although it is true that larger RPN values normally indicate more critical failure modes, this is not always the case. For example, here we have three cases where the RPNs are identical, but clearly the second case would warrant the most attention.

As a general rule, any failure mode that has an effect resulting in a severity 9 or 10 would have top priority. Severity is given the most weight when assessing risk. Next, the Severity and Occurrence (S x O) combination would be considered, since this in effect, represents the criticality.

Because the RPN is the product of three ratings, different circumstances can produce similar or identical RPNs. For example, an RPN of 100 can occur when S = 10, O = 2 and D = 5; when S = 1, O = 10 and D = 10; when S = 4, O = 5 and D = 5, etc. In addition, it may not be appropriate to give equal weight to the three ratings that comprise the RPN. For example, an organization may consider issues with high severity and/or high occurrence ratings to represent a higher risk than issues with high detection ratings. Therefore, basing decisions solely on the RPN (considered in isolation) may result in inefficiency and/or increased risk.

Below is another RPN example reminding us that we need to be careful not to assess risk purely based on the RPN values. Here, the failure modes with the lowest RPN values are actually the most critical. Be careful to not just establish "threshold values" for RPNs when assessing risk, as this could lead you to make costly mistakes. Below we see that #1 is most critical even though it has the lowest RPN value, then #2, and then #3.

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In summary, always address high severity failure modes regardless of their overall RPN

values.

2.3 Revised RPNs and Percent Reduction in RPN:

In some cases, it may be appropriate to revise the initial risk assessment based on the assumption (or the fact) that the recommended actions have been completed. This provides an indication of the effectiveness of corrective actions and can also be used to evaluate the value to the organization of performing the FMEA. To calculate revised RPNs, the analysis team assigns a second set of Severity, Occurrence and Detection ratings for each issue (using the same rating scales) and multiplies the revised ratings to calculate the revised RPNs. If both initial and revised RPNs have been assigned, the percent reduction in RPN can also be calculated as follows:

For example, if the initial ratings for a potential problem are S = 7, O = 8 and D = 5 and the revised ratings are S = 7, O = 6 and D = 4, then the percent reduction in RPN from initial to revised is (280-168)/280, or 40%. This indicates that the organization was able to reduce the risk associated with the issue by 40% through the performance of the FMEA and the implementation of corrective actions.

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Rank Issues by Severity, Occurrence or Detection: Ranking issues according to their individual Severity, Occurrence or Detection ratings is another way to analyze potential problems. For example, the organization may determine that corrective action is required for any issue with an RPN that falls within a specified range and also for any issue with a high severity rating. In this case, a potential problem may have an RPN of 40 (Severity = 10, Occurrence = 2 and Detection = 2). This may not be high enough to trigger corrective action based on RPN but the analysis team may decide to initiate a corrective action anyway because of the very high severity of the potential effect of the failure.

2.4 Risk Ranking Tables

In addition to, or instead of, the other risk assessment tools described here, the organization may choose to develop risk ranking tables to assist the decision-making process. These tables will typically identify whether corrective action is required based on some combination of Severity, Occurrence, Detection and/or RPN values. As an example, the table in Figure 4 places Severity horizontally and Occurrence vertically

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Figure 4: Sample risk ranking table

The letters and numbers inside the table indicate whether a corrective action is required for each case.

N = No corrective action needed. C = Corrective action needed. # = Corrective action needed if the Detection rating is equal to or greater than the given

number. For example, according to the risk ranking table in Figure 4, if Severity = 6 and Occurrence = 5, then corrective action is required if Detection = 4 or higher. If Severity = 9 or 10, then corrective action is always required. If Occurrence = 1 and Severity = 8 or lower, then corrective action is never required, and so on. Other variations of this decision-making table are possible and the appropriate table will be determined by the organization or analysis team based on the characteristics of the product or process being analyzed and other organizational factors, such as budget, customer requirements, applicable legal regulations, etc.

2.5 Conclusion

The RPN is not a measure of risk, but of risk priority. The Risk Priority Number (RPN) methodology can be used to assess the risk associated with potential problems in a product or process design and to prioritize issues for corrective action. A particular analysis team may choose to supplement or replace the basic RPN methodology with other related techniques,

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such as revised RPNs, the Occurrence/Severity matrix, ranking lists, risk ranking tables and/or higher level RPNs. All of these techniques rely heavily on engineering judgment and must be customized to fit the product or process that is being analyzed and the particular needs/priorities of the organization.Reserve Bank of India(RBI) uses the technique of RPN to prioritize risks and mitigate those risks by taking corrective and preventive actions.

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3.0 Force Field Analysis

Force Field Analysis is a useful technique for looking at all the forces for and against a decision. In effect, it is a specialized method of weighing pros and cons.By carrying out the analysis you can plan to strengthen the forces supporting a decision, and reduce the impact of opposition to it.To carry out a force field analysis, one needs to use the follow these steps: Describe your plan or proposal for change in the middle.

List all forces for change in one column, and all forces against change in another column.

Assign a score to each force, from 1 (weak) to 5 (strong).

For example, imagine that one is a manager deciding whether to install new manufacturing equipment in his factory. One needs to draw up a force field analysis like the one in Figure 1:

Once he has carried out an analysis, he can decide whether that project is viable. In the example above, initially question arises whether it is worth going ahead with the plan.

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Where one has already decided to carry out a project, Force Field Analysis can help to work out how to improve its probability of success. Here we have two choices: To reduce the strength of the forces opposing a project.

To increase the forces pushing a project.

Often the most elegant solution is the first: just trying to force change through may cause its own problems. People can be uncooperative if change is forced on them.If we had to implement the project in the example above, the analysis might suggest a number of changes to the initial plan: By training staff (increase cost by 1) we can eliminate fear of technology (reduce fear

by 2)

It would be useful to show staff that change is necessary for business survival (new force in favor, +2)

Staff could be shown that new machines would introduce variety and interest to their jobs (new force, +1)

One can raise wages to reflect new productivity (cost +1, loss of overtime -2)

Slightly different machines with filters to eliminate pollution could be installed (environmental impact -1)

These changes would swing the balance from 11:10 (against the plan), to 8:13 (in favor of the plan).

Force Field Analysis is a useful technique for looking at all the forces for and against a plan. It helps one weigh the importance of these factors and decide whether a plan is worth implementing.Where one has decided to carry out a plan, Force Field Analysis helps us identify changes that one could make to improve it.

The process goes something like this-

Revise the brainstorming rules

3.1 BRAINSTORMING RULESSay the first thing that pops into your mind

Do not be judgemental of your or others ideas

Contributors do not have to justify their ideas

Do not interrupt the other person

The wilder the idea the better the idea

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Do not be constrained by convention

Think out of the square

Quantity not necessarily quality initially

Every person and every idea has equal worth

Build on the ideas put forward by others

Sometimes one may wish to have a fun exercise to practice the brainstorming technique to start with. One exercise had a number of OHS professionals one of whom ran a take-away shop as an extra business. We brainstormed how to increase the sales of fish & chips at a store. One of the members may have a hobby or activity they are trying to improve and we can brainstorm how to help them improve. Main thing is light-hearted & not too serious.

2 Brainstorm an objective or objectives for the Management System .

3 Brainstorm the promoting / facilitating forces acting towards the objective

4 Brainstorm the constraining / restraining forces acting against the objective

5 Develop an action plan to boost the facilitating / promoting forces and negate the constraining / restraining forces.

Discussion needs to be recorded on butchers paper, on a recording whiteboard ( Check beforehand that it is working and there is an adequate supply of paper) or on the fly with a lap-top & data projector. Always have butchers paper, black & blue markers and blu-tac available in case the technology fails or the power goes out. One of the outcomes of the above discussion is that you will define a number of the good things you are already doing in the area being considered, in itself, not a bad thing.

Always make sure you feedback the results of the discussions to the participants and, once decided, what actions resulted from the discussions.

Required actions may need dividing into those the business unit has responsibility for and those corporate has responsibility for.

The deliberations above may assist in the development of strategic and operational management plans.

[MBA-IM 2011-13]


3.2 Advantages of force-field analysis Involves a wide cross-section of stakeholders in meaningful discussions about the

topic Places a high profile on the topic Helps with defining and documenting the things you are already doing in the area Helps to identify the deficiencies in the current Management System With a highly skilled facilitator helps to develop innovative solutions and

improvements

NoteRequires a highly skilled facilitator to develop trust with the participants and “surface” the issues, people often “spill their guts” on a whole range of previously unsurfaced issues. It can, to a certain extent, be a healing process where those aggrieved get a chance to unload their problems.

The real danger is people with hobby horses, it requires some skill to be seen to be interested without having particular issues take over.

For complex issues and / or a large group 2.5-3 hours may be required. The process can be hard work and tiring, monitor how people are going and possibly schedule a second session. Have regular short, sharp breaks.

Very important-Have water & glasses on the table, fruit if possible, aids concentration

3.2.1 ExamplePurpose: To identify the factors or forces that either support or work against a desired outcome.

Method:

Draw a "T" shape as shown below.Brainstorm the forces that will assist you in achieving the desired outcome. List them on the left side of the vertical line.Brainstorm the forces that may prevent or restrain you from reaching your outcome. List them on the right side of the line. •(Optional) Prioritize the driving forces (left side) and/or the restraining forces (right side).Look for opportunities to take advantage of or strengthen driving forces.

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Identify restraining forces that you might be able to eliminate (or reduce the "force" or impact).It is often more helpful to eliminate restraining forces than attempting to strengthen driving forces. In most cases, the driving forces will remain present and continue to help you even if you do nothing to strengthen them; whereas eliminating restraining forces can have significant benefits in achieving your objective/outcome.In a "pound-for-pound" or "best bang for the buck" fashion, the force field analysis is one of the most powerful tools in terms of the effort required to generate it and the potential benefits derived from it.Restraining forces can also be identified as potential risks, and entered into the risk management tracking system.

Example

4.0 Bibliography:

http://www.fmea-fmeca.com/fmea-rpn.htmlhttp://www.reliasoft.com/newsletter/2q2003/rpns.htmhttp://www.ombuenterprises.com/LibraryPDFs/Understanding_Risk_Priority_Numbers.pdfwww.sixsigmaspc.com/dictionary/RPN-riskprioritynumber.html

[MBA-IM 2011-13]

risk management techniques - web viewrisk management identifies hazards and tracks them through a...

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