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Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Always consider a SINGLE failure at the worst time.. high flow, high demand, bad weather etc..  Only consider a secondary failure with safety devices.  An example is a fire extinguisher, fire alarm, smoke detector, etc. has no consequence of failure unless there is a secondary failure...a fire.  I believe the same is true with your div 1 class 1 scenario.  The consequence only occurs if you have TWO failures....a bad atmosphere (high LEL) and an ignition source.  I would assume that you have gas detectors to warn you of a high LEL.

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Thanks for your help, Jeffrey. 

Just wanted to make sure that I understand.  For example, we had a guard on our rotogravure press that fell and rubbed on a rotating cylinder, which would have resulted in a spark and an explosion if the operator hadn't caught it.  Would the guard falling and causing a spark be considered the single failure?

How would you rate the likelihood of this failure since it was the first time that it happened in over 20 years?

Always consider a SINGLE failure at the worst time.. high flow, high demand, bad weather etc..  Only consider a secondary failure with safety devices.  An example is a fire extinguisher, fire alarm, smoke detector, etc. has no consequence of failure unless there is a secondary failure...a fire.  I believe the same is true with your div 1 class 1 scenario.  The consequence only occurs if you have TWO failures....a bad atmosphere (high LEL) and an ignition source.  I would assume that you have gas detectors to warn you of a high LEL.

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Thanks for your help, Jeffrey. 

Just wanted to make sure that I understand.  For example, we had a guard on our rotogravure press that fell and rubbed on a rotating cylinder, which would have resulted in a spark and an explosion if the operator hadn't caught it.  Would the guard falling and causing a spark be considered the single failure?

How would you rate the likelihood of this failure since it was the first time that it happened in over 20 years?

Always consider a SINGLE failure at the worst time.. high flow, high demand, bad weather etc..  Only consider a secondary failure with safety devices.  An example is a fire extinguisher, fire alarm, smoke detector, etc. has no consequence of failure unless there is a secondary failure...a fire.  I believe the same is true with your div 1 class 1 scenario.  The consequence only occurs if you have TWO failures....a bad atmosphere (high LEL) and an ignition source.  I would assume that you have gas detectors to warn you of a high LEL.

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Andrew,

I have worked with a number of clients to establish an asset criticality assessment (ACA) process.  It's important to remember that the ACA process is intended to help you optimize your resource investment in improving reliability.  It is meant to identify the most "critical" systems and assets and the least critical systems and assets.  Knowing if an asset is number 12 or number 10 on that list isn't the goal.  Therefore a consistent, fact based, ranking method, that can be performed consistently and cost effectively, by different teams, is what is important. 

As you, and others, point out, you need to determine the likelihood of an event (i.e. asset failure caused event) and the impact of that event.  As you note, that is generally done for multiple categories and one event may have varying consequences for the various categories.  This leads to a choice of how to treat the various "risk" results by system and by asset.  The two methods that we used were to either use the highest single risk (i.e. probability X consequence) or to use the sum of the top risks by category.  The ranked order of the risk results are very dependent on how you choose to quantify your consequences of an asset failure.  How does a serious personnel injury event compare to a day of lost production?  All of that said, if you have a well documented definition and process, you can present and defend your results to your stakeholders with confidence.  Debate can then focus on how you quantified the risks.  If that changes, you can quickly update your rankings.  Even when that happens, the rank order will likely not change dramatically. 

I know it's a long answer to a short question. 

Regards,

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Thanks for your help, I appreciate the "long answer".  This is the risk matrix that we developed.  We are only defining the consequence and scaling it based on what we felt was more important. 

Forgive my ignorance, but I'm still confused about how to score the likelihood.  For example, if we safety=4 (may result in death) and quality=4, then how should I score the likelihood of the asset failure?  Is it based on how often the asset fails (MTBF.  Note:  we didn't include MTBF in the matrix since we just got a new CMMS and do not have that data) or the likelihood that the failure may result in death (due to the safety score) and/or the likelihood that it may result in a significant quality defect?

Andrew,

I have worked with a number of clients to establish an asset criticality assessment (ACA) process.  It's important to remember that the ACA process is intended to help you optimize your resource investment in improving reliability.  It is meant to identify the most "critical" systems and assets and the least critical systems and assets.  Knowing if an asset is number 12 or number 10 on that list isn't the goal.  Therefore a consistent, fact based, ranking method, that can be performed consistently and cost effectively, by different teams, is what is important. 

As you, and others, point out, you need to determine the likelihood of an event (i.e. asset failure caused event) and the impact of that event.  As you note, that is generally done for multiple categories and one event may have varying consequences for the various categories.  This leads to a choice of how to treat the various "risk" results by system and by asset.  The two methods that we used were to either use the highest single risk (i.e. probability X consequence) or to use the sum of the top risks by category.  The ranked order of the risk results are very dependent on how you choose to quantify your consequences of an asset failure.  How does a serious personnel injury event compare to a day of lost production?  All of that said, if you have a well documented definition and process, you can present and defend your results to your stakeholders with confidence.  Debate can then focus on how you quantified the risks.  If that changes, you can quickly update your rankings.  Even when that happens, the rank order will likely not change dramatically. 

I know it's a long answer to a short question. 

Regards,

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

There are different ways to approach this as you have seen. I agree that as long as you follow typical conventions and have a well documented process you will get good results you can stand by. 

1.) Single point failure is important to define and consider under this analysis. If the asset in question could possibly result in a hidden failure (the smoke alarm example) then I have marked as so and treated these items separately. We perform PHA and ACA analysis. Where the PHA is concerning the worst case scenario for process safety consideration. For our ACA more focused on reliability, I look at the most likely consequence of failure at the likely first detection.  I typically would not focus on the worst case imaginable for my ACA. In your example of a class 1 div 1 area. It may be reasonable to expect an explosion resulting in death as I don't know the process.

2.) You should be considering the likelihood of the asset failure. The asset fails when the asset fails. The safety consequence is very high, and that will be reflected in the final results. The likelihood that the asset won't perform it's intended function is improved by different actions then the actions to reduce the consequence. There may be exceptions but I believe that is typically how it is treated. 

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Thanks for your help, Jesse.  I replied to a couple of the other messages and would love your feedback as well...

For example, we had a guard on our rotogravure press that fell and rubbed on a rotating cylinder, which would have resulted in a spark and an explosion if the operator hadn't caught it.  Would the guard falling and causing a spark be considered the single failure?  How would you rate the likelihood of this failure since it was the first time that it happened in over 20 years?

Forgive my ignorance, but I'm still confused about how to score the likelihood.  For example, if we safety=4 (may result in death) and quality=4, then how should I score the likelihood of the asset failure?  Is it based on how often the asset fails (MTBF.  Note:  we didn't include MTBF in the matrix since we just got a new CMMS and do not have that data) or the likelihood that the failure may result in death (due to the safety score) and/or the likelihood that it may result in a significant quality defect?  (This is the risk matrix that we developed.  We are only defining the consequence and scaling it based on what we felt was more important)

There are different ways to approach this as you have seen. I agree that as long as you follow typical conventions and have a well documented process you will get good results you can stand by. 

1.) Single point failure is important to define and consider under this analysis. If the asset in question could possibly result in a hidden failure (the smoke alarm example) then I have marked as so and treated these items separately. We perform PHA and ACA analysis. Where the PHA is concerning the worst case scenario for process safety consideration. For our ACA more focused on reliability, I look at the most likely consequence of failure at the likely first detection.  I typically would not focus on the worst case imaginable for my ACA. In your example of a class 1 div 1 area. It may be reasonable to expect an explosion resulting in death as I don't know the process.

2.) You should be considering the likelihood of the asset failure. The asset fails when the asset fails. The safety consequence is very high, and that will be reflected in the final results. The likelihood that the asset won't perform it's intended function is improved by different actions then the actions to reduce the consequence. There may be exceptions but I believe that is typically how it is treated. 

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Andrew,

You've received some solid guidance from the other posters, but I wanted to point out an important aspect of your question that is a major factor in how you can use the results of your analysis.

The analysis tool you're using is asking for both the consequences and the probability of a failure event for each asset. (Consequence of failure) * (Probability of failure) is actually the formula for risk, not criticality. While you definitely want to base your asset decision-making around the risk of failure, it's important to keep in mind that the probability of failure will change whenever the condition of the asset changes (e.g. maintenance intervention, degradation from use, asset replacement). The consequence of failure will only change when the asset function changes (e.g. system re-design).

Therefore, I prefer to keep asset criticality and asset risk as separate ideas and values. Changes in asset criticality (consequence of failure) can be managed through your Management of Change process. Changes in asset risk (consequence * probability) requires more dynamic management, with inputs from on-line monitoring, inspection results, and work orders completed.

Feel free to message me if you'd like to discuss further.

~~~~

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!

Good morning!

I'm attempting my first asset criticality analysis and I have a couple questions...

1.)  When we score each category, are we assuming that the worst, most plausible scenario occurs?  For example, safety:  we have rotogravure presses that have class 1 div 1 areas.  The worst case scenario would be an explosion that could result in death.

2.)  I received an asset criticality analysis template from the Mobius Institute (iLearnReliability) and it multiplies the likelihood against the sum of all the scores (for example, safety, environmental, production, quality).  I'm confused by this since the likelihood of an explosion in a class 1 div 1 area (as mentioned above) should be low compared to a production loss of over $10k. I would think that we should assign a different likelihood for each category.

Any help would be greatly appreciated!