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Re: Extent of Condition - How far is reasonable

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  • Judd Sills
    Roger- Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who
    Message 1 of 11 , Feb 2, 2013
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      Roger-
      Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who performed the work has been to our facility and performed this and other maintenance tasks on the engines several times in the past. We are not able to confirm that the pin was actually installed when it needed to be installed, but we did find a used, straightened pin in the general vicinity of where it might have fallen earlier in the maintenance work when it was removed, or it could have been that the pin was straightened when removed and the mechanic intended to reuse it and either forgot to install it, or failed to bend the tines. Too much time had passed for anyone to reliably indicate what happened. The other complicating factor was that the cotter pin was not on the work order bill of materials, so the mechanic could have set the old pin aside intending to obtain a new like-for-like replacement. The idea of looking at work performed by vendors involving cotter pin replacement is a good starting point to narrow the scope down. Our oversight of the contractor was LTA, so I don;t think that I could simply state that we believe it is an issue confined to this vendor as we were not paying sufficient attention to what they were doing to rule out other vendor supplied labor entirely.

      As far as general risk classification, the EDG is classified as a Mitigating System that supports Engineered Safety Features in hypothetical design base accidents. I suppose that I could winnow my EOCo down to other Mitigating Systems (there are in general, four others) that had vendor work performed that would have involved cotter pins. That might get me closer to something that I could get my arms around. Frankly, I'm not certain that I could make a convincing argument that the error would be confined to vendors however. A battle that I had to fight during the cause evaluation was that regardless of whether we consider proper installation of a cotter pin within the "skill of the craft," if the pin serves a function that if not properly completed could result in the inoperability of a required system, then we must call out that installation step and add measures such as independent verification to know that it was completed.

      As far as past failures, my internal OE search turned up a few cases of missing cotter pins on important safety systems at our site, but only ~5. My external OE search, however, turned up lots of examples (62 very similar cases) on lots of systems. It was the OE search that left me with the conundrum regarding the means to convincingly narrow my target population down to a manageable size.

      I do like the idea of using the vendor performed work as a starting point, and then looking at the work orders involving cotter pin replacement, confining that to work on systems classified as mitigating systems. At least this would allow us to begin the search by doing desk review first. We are entering a refueling outage soon, so we could perform inspections on most identified cases if I move quickly.

      Thanks for the great ideas. I guess that I should have gotten there on my own, but was overwhelmed by the external OE population suggested.
      Have a great day
      Judd
    • Roger Willmott
      Judd Just a couple of more thoughts - prevention is fairly simple for future activities; Never reuse cotter pins - it may increase costs but once a cotter pin
      Message 2 of 11 , Feb 2, 2013
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        Judd

        Just a couple of more thoughts - prevention is fairly simple for future activities;
        Never reuse cotter pins - it may increase costs but once a cotter pin has been manipulated in any way its characteristics will change, this is especially true for high potential consequence applications.
        Ensure the task risk assessment includes all steps of the task, either in the technical data supplied with the equipment, (passport or maintenance instructions), and or local work orders.
        Good housekeeping is essential for any technical maintenance work. The original cotter pin (if it was original) would have been seen easily at the sign off stage of the maintenance work if good housekeeping was being followed. Regardless of space limitations, there should be a clean lay down area for any article removed from a machine during maintenance and breakdown repair activities. This should be matched with a clean lay down area for replacement new or reworked parts that will eventually be fitted to the machine.

        In my youth I had 22 years carrying a toolbox on mechanical maintenance activities in Marine (ships) and Oil and Gas offshore and onshore work sites. In later years I was supervising and then managing these activities.

        Take care
        Roger................
        Keep it simple, than even I might understand it.


        From: Judd Sills <sillsj@...>
        To: Root_Cause_State_of_the_Practice@yahoogroups.com
        Sent: Saturday, February 2, 2013 8:57 PM
        Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable

         
        Roger-
        Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who performed the work has been to our facility and performed this and other maintenance tasks on the engines several times in the past. We are not able to confirm that the pin was actually installed when it needed to be installed, but we did find a used, straightened pin in the general vicinity of where it might have fallen earlier in the maintenance work when it was removed, or it could have been that the pin was straightened when removed and the mechanic intended to reuse it and either forgot to install it, or failed to bend the tines. Too much time had passed for anyone to reliably indicate what happened. The other complicating factor was that the cotter pin was not on the work order bill of materials, so the mechanic could have set the old pin aside intending to obtain a new like-for-like replacement. The idea of looking at work performed by vendors involving cotter pin replacement is a good starting point to narrow the scope down. Our oversight of the contractor was LTA, so I don;t think that I could simply state that we believe it is an issue confined to this vendor as we were not paying sufficient attention to what they were doing to rule out other vendor supplied labor entirely.

        As far as general risk classification, the EDG is classified as a Mitigating System that supports Engineered Safety Features in hypothetical design base accidents. I suppose that I could winnow my EOCo down to other Mitigating Systems (there are in general, four others) that had vendor work performed that would have involved cotter pins. That might get me closer to something that I could get my arms around. Frankly, I'm not certain that I could make a convincing argument that the error would be confined to vendors however. A battle that I had to fight during the cause evaluation was that regardless of whether we consider proper installation of a cotter pin within the "skill of the craft," if the pin serves a function that if not properly completed could result in the inoperability of a required system, then we must call out that installation step and add measures such as independent verification to know that it was completed.

        As far as past failures, my internal OE search turned up a few cases of missing cotter pins on important safety systems at our site, but only ~5. My external OE search, however, turned up lots of examples (62 very similar cases) on lots of systems. It was the OE search that left me with the conundrum regarding the means to convincingly narrow my target population down to a manageable size.

        I do like the idea of using the vendor performed work as a starting point, and then looking at the work orders involving cotter pin replacement, confining that to work on systems classified as mitigating systems. At least this would allow us to begin the search by doing desk review first. We are entering a refueling outage soon, so we could perform inspections on most identified cases if I move quickly.

        Thanks for the great ideas. I guess that I should have gotten there on my own, but was overwhelmed by the external OE population suggested.
        Have a great day
        Judd



      • Dr. Bill Corcoran
        Judd, It s hard to stick to the topic of extent when the event is so full of missed opportunities. I ll provide more thoughts when I return to the office. It
        Message 3 of 11 , Feb 3, 2013
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          Judd,

          It's hard to stick to the topic of extent when the event is so full of missed opportunities.

          I'll provide more thoughts when I return to the office.

          It would be interesting to see the investigation report for which you are doing the extent.

          All the best,

          Bill

          Sent from my iPhone



          On Feb 2, 2013, at 9:51 PM, Roger Willmott <willmottr@...> wrote:

           

          Judd

          Just a couple of more thoughts - prevention is fairly simple for future activities;
          Never reuse cotter pins - it may increase costs but once a cotter pin has been manipulated in any way its characteristics will change, this is especially true for high potential consequence applications.
          Ensure the task risk assessment includes all steps of the task, either in the technical data supplied with the equipment, (passport or maintenance instructions), and or local work orders.
          Good housekeeping is essential for any technical maintenance work. The original cotter pin (if it was original) would have been seen easily at the sign off stage of the maintenance work if good housekeeping was being followed. Regardless of space limitations, there should be a clean lay down area for any article removed from a machine during maintenance and breakdown repair activities. This should be matched with a clean lay down area for replacement new or reworked parts that will eventually be fitted to the machine.

          In my youth I had 22 years carrying a toolbox on mechanical maintenance activities in Marine (ships) and Oil and Gas offshore and onshore work sites. In later years I was supervising and then managing these activities.

          Take care
          Roger................
          Keep it simple, than even I might understand it.


          From: Judd Sills <sillsj@...>
          To: Root_Cause_State_of_the_Practice@yahoogroups.com
          Sent: Saturday, February 2, 2013 8:57 PM
          Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable

           
          Roger-
          Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who performed the work has been to our facility and performed this and other maintenance tasks on the engines several times in the past. We are not able to confirm that the pin was actually installed when it needed to be installed, but we did find a used, straightened pin in the general vicinity of where it might have fallen earlier in the maintenance work when it was removed, or it could have been that the pin was straightened when removed and the mechanic intended to reuse it and either forgot to install it, or failed to bend the tines. Too much time had passed for anyone to reliably indicate what happened. The other complicating factor was that the cotter pin was not on the work order bill of materials, so the mechanic could have set the old pin aside intending to obtain a new like-for-like replacement. The idea of looking at work performed by vendors involving cotter pin replacement is a good starting point to narrow the scope down. Our oversight of the contractor was LTA, so I don;t think that I could simply state that we believe it is an issue confined to this vendor as we were not paying sufficient attention to what they were doing to rule out other vendor supplied labor entirely.

          As far as general risk classification, the EDG is classified as a Mitigating System that supports Engineered Safety Features in hypothetical design base accidents. I suppose that I could winnow my EOCo down to other Mitigating Systems (there are in general, four others) that had vendor work performed that would have involved cotter pins. That might get me closer to something that I could get my arms around. Frankly, I'm not certain that I could make a convincing argument that the error would be confined to vendors however. A battle that I had to fight during the cause evaluation was that regardless of whether we consider proper installation of a cotter pin within the "skill of the craft," if the pin serves a function that if not properly completed could result in the inoperability of a required system, then we must call out that installation step and add measures such as independent verification to know that it was completed.

          As far as past failures, my internal OE search turned up a few cases of missing cotter pins on important safety systems at our site, but only ~5. My external OE search, however, turned up lots of examples (62 very similar cases) on lots of systems. It was the OE search that left me with the conundrum regarding the means to convincingly narrow my target population down to a manageable size.

          I do like the idea of using the vendor performed work as a starting point, and then looking at the work orders involving cotter pin replacement, confining that to work on systems classified as mitigating systems. At least this would allow us to begin the search by doing desk review first. We are entering a refueling outage soon, so we could perform inspections on most identified cases if I move quickly.

          Thanks for the great ideas. I guess that I should have gotten there on my own, but was overwhelmed by the external OE population suggested.
          Have a great day
          Judd



        • Judd Sills
          Roger- All valid thoughts and I have already captured those issues in corrective actions in the report. This was probably my best experience with the OE search
          Message 4 of 11 , Feb 3, 2013
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            Roger-
            All valid thoughts and I have already captured those issues in corrective actions in the report. This was probably my best experience with the OE search actually telling me something that I didn't already know. A new failure mode, an undersized cotter pin, became evident from a few of the external reports reviewed, and that sent me to create a new CA that we didn't have. I have used your ideas on proposing a different target population on that extent of condition, and I'm hopeful that the station will consider it rational and well reasoned. Your feedback was very helpful in getting me over the OMG threshold of what is reasonable. I should have seen that answer myself, but nonetheless, was overwhelmed by what I saw in the OE. I've never had that many hits come back that were valid, and the targets were everywhere.

            --- In Root_Cause_State_of_the_Practice@yahoogroups.com, Roger Willmott wrote:
            >
            > Judd
            >
            > Just a couple of more thoughts - prevention is fairly simple for future activities;
            > Never reuse cotter pins - it may increase costs but once a cotter pin has been manipulated in any way its characteristics will change, this is especially true for high potential consequence applications.
            > Ensure the task risk assessment includes all steps of the task, either in the technical data supplied with the equipment, (passport or maintenance instructions), and or local work orders.
            > Good housekeeping is essential for any technical maintenance work. The original cotter pin (if it was original) would have been seen easily at the sign off stage of the maintenance work if good housekeeping was being followed. Regardless of space limitations, there should be a clean lay down area for any article removed from a machine during maintenance and breakdown repair activities. This should be matched with a clean lay down area for replacement new or reworked parts that will eventually be fitted to the machine.
            >
            > In my youth I had 22 years carrying a toolbox on mechanical maintenance activities in Marine (ships) and Oil and Gas offshore and onshore work sites. In later years I was supervising and then managing these activities.
            >
            > Take care
            > Roger................
            > Keep it simple, than even I might understand it.
            >
            >
            > ________________________________
            > From: Judd Sills
            > To: Root_Cause_State_of_the_Practice@yahoogroups.com
            > Sent: Saturday, February 2, 2013 8:57 PM
            > Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable
            >
            >
            >  
            > Roger-
            > Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who performed the work has been to our facility and performed this and other maintenance tasks on the engines several times in the past. We are not able to confirm that the pin was actually installed when it needed to be installed, but we did find a used, straightened pin in the general vicinity of where it might have fallen earlier in the maintenance work when it was removed, or it could have been that the pin was straightened when removed and the mechanic intended to reuse it and either forgot to install it, or failed to bend the tines. Too much time had passed for anyone to reliably indicate what happened. The other complicating factor was that the cotter pin was not on the work order bill of materials, so the mechanic could have set the old pin aside intending to obtain a new like-for-like replacement. The
            > idea of looking at work performed by vendors involving cotter pin replacement is a good starting point to narrow the scope down. Our oversight of the contractor was LTA, so I don;t think that I could simply state that we believe it is an issue confined to this vendor as we were not paying sufficient attention to what they were doing to rule out other vendor supplied labor entirely.
            >
            > As far as general risk classification, the EDG is classified as a Mitigating System that supports Engineered Safety Features in hypothetical design base accidents. I suppose that I could winnow my EOCo down to other Mitigating Systems (there are in general, four others) that had vendor work performed that would have involved cotter pins. That might get me closer to something that I could get my arms around. Frankly, I'm not certain that I could make a convincing argument that the error would be confined to vendors however. A battle that I had to fight during the cause evaluation was that regardless of whether we consider proper installation of a cotter pin within the "skill of the craft," if the pin serves a function that if not properly completed could result in the inoperability of a required system, then we must call out that installation step and add measures such as independent verification to know that it was completed.
            >
            > As far as past failures, my internal OE search turned up a few cases of missing cotter pins on important safety systems at our site, but only ~5. My external OE search, however, turned up lots of examples (62 very similar cases) on lots of systems. It was the OE search that left me with the conundrum regarding the means to convincingly narrow my target population down to a manageable size.
            >
            > I do like the idea of using the vendor performed work as a starting point, and then looking at the work orders involving cotter pin replacement, confining that to work on systems classified as mitigating systems. At least this would allow us to begin the search by doing desk review first. We are entering a refueling outage soon, so we could perform inspections on most identified cases if I move quickly.
            >
            > Thanks for the great ideas. I guess that I should have gotten there on my own, but was overwhelmed by the external OE population suggested.
            > Have a great day
            > Judd
            >
          • Kay Wilde Gallogly
            Judd , In reading the discussion I am seeing target used in association with an extent of condition. In working with the IEEE subcommittee on Human Factors to
            Message 5 of 11 , Feb 4, 2013
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              Judd ,

               

              In reading the discussion I am seeing target used in association with an extent of condition.  In working with the IEEE subcommittee on Human Factors to gain the approval for the recommended practice for event investigation I have become acutely aware of the words that we use in event investigations.  I think Bill Corcoran made this point in a recent discussion was well with his observation that there are over 35 definitions of root cause.  It may be that people have resorted to the term target in connection with extent of condition because the term condition is used in different contexts in event investigations as well.   First in the context of the condition that is the event that is being investigated and secondly in event and causal factor charting meaning the ‘stuff’ the contributed to the actions or events.  I am interested to hear more about the use of the term target in the context of extent of condition.  The definition that I am familiar with is that it is the asset that we are interested in protecting.  I am more familiar with the term target in a barrier analysis.  Would this then default to the condition in the extent of condition being the asset that is to be protected?  Is there another definition of target in the context of extent of condition? 

               

              My sense is that the investigation for the cotter pin is being reviewed as a function of additional regulatory interest.  The diesel overhaul took place in December of 2010.  That being said, I would encourage you to go back to the NRC definition of extent of condition found in NRC Inspection Manual 95002.  Which is: “Extent of Condition is defined as the extent to which the actual condition exists with other plant processes, equipment, or human performance.”  (Emphasis is mine) In conducting research not only for the IEEE recommended practice but for my own practice my understanding is that the purpose of the extent of condition review is to identify any immediate vulnerability to the plant equipment, people, or public from the same condition.  The purpose being to put in place contingencies or immediate actions until the event investigation identifies the actual causes.  Again, in my research, the recommendation is that the extent of cause analysis be completed immediately prior to the completion of the event investigation.  At the point the extent of condition analysis is completed, a practitioner would not have the benefit of the investigation.  This learning is captured in the extent of cause.  Which is defined in NRC Inspection Manual 95002 as:  “Extent of Cause is defined as the extent to which the root causes of an identified problem have impacted other plant processes, equipment, or human performance.”  (Emphasis is mine)  Again going back to the theory as I understand it, the root cause(s) would reflect the missed opportunities.  So they are captured in the extent analysis but at the extent of cause rather than the extent of condition.

               

              I am probably reiterating what you all know.  However, it is my observation that in many cases we, as an industry, make the extent of condition and extent of cause analysis more difficult than what it needs to be if we go back to the basic premise of what their role is in the investigation.  Extent of condition and extent of cause are not easy.  The analysis is very important and receives a lot of scrutiny.  A suggestion is that if the extent of condition analysis is completed immediately, to look for that immediate vulnerability in whether the same condition exists in another unit, a redundant system, etc. that it is easier.  If the extent of condition is left until the end of the event investigation it is easy to start getting confused with information that was gathered during the analysis of the event and the actual condition is lost.

               

              Thoughts?

               

              Kay

               

               

              From: Root_Cause_State_of_the_Practice@yahoogroups.com [mailto:Root_Cause_State_of_the_Practice@yahoogroups.com] On Behalf Of Judd Sills
              Sent: Sunday, February 03, 2013 2:30 PM
              To: Root_Cause_State_of_the_Practice@yahoogroups.com
              Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable

               

               

              Roger-
              All valid thoughts and I have already captured those issues in corrective actions in the report. This was probably my best experience with the OE search actually telling me something that I didn't already know. A new failure mode, an undersized cotter pin, became evident from a few of the external reports reviewed, and that sent me to create a new CA that we didn't have. I have used your ideas on proposing a different target population on that extent of condition, and I'm hopeful that the station will consider it rational and well reasoned. Your feedback was very helpful in getting me over the OMG threshold of what is reasonable. I should have seen that answer myself, but nonetheless, was overwhelmed by what I saw in the OE. I've never had that many hits come back that were valid, and the targets were everywhere.

              --- In Root_Cause_State_of_the_Practice@yahoogroups.com, Roger Willmott wrote:
              >
              > Judd
              >
              > Just a couple of more thoughts - prevention is fairly simple for future activities;
              > Never reuse cotter pins - it may increase costs but once a cotter pin has been manipulated in any way its characteristics will change, this is especially true for high potential consequence applications.
              > Ensure the task risk assessment includes all steps of the task, either in the technical data supplied with the equipment, (passport or maintenance instructions), and or local work orders.
              > Good housekeeping is essential for any technical maintenance work. The original cotter pin (if it was original) would have been seen easily at the sign off stage of the maintenance work if good housekeeping was being followed. Regardless of space limitations, there should be a clean lay down area for any article removed from a machine during maintenance and breakdown repair activities. This should be matched with a clean lay down area for replacement new or reworked parts that will eventually be fitted to the machine.
              >
              > In my youth I had 22 years carrying a toolbox on mechanical maintenance activities in Marine (ships) and Oil and Gas offshore and onshore work sites. In later years I was supervising and then managing these activities.
              >
              > Take care
              > Roger................
              > Keep it simple, than even I might understand it.
              >
              >
              > ________________________________
              > From: Judd Sills
              > To: Root_Cause_State_of_the_Practice@yahoogroups.com
              > Sent: Saturday, February 2, 2013 8:57 PM
              > Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable
              >
              >
              >  
              > Roger-
              > Excellent suggestions. Here is what we have. The vendor that performed this work is the component manufacturer at our facility. The technician who performed the work has been to our facility and performed this and other maintenance tasks on the engines several times in the past. We are not able to confirm that the pin was actually installed when it needed to be installed, but we did find a used, straightened pin in the general vicinity of where it might have fallen earlier in the maintenance work when it was removed, or it could have been that the pin was straightened when removed and the mechanic intended to reuse it and either forgot to install it, or failed to bend the tines. Too much time had passed for anyone to reliably indicate what happened. The other complicating factor was that the cotter pin was not on the work order bill of materials, so the mechanic could have set the old pin aside intending to obtain a new like-for-like replacement. The
              > idea of looking at work performed by vendors involving cotter pin replacement is a good starting point to narrow the scope down. Our oversight of the contractor was LTA, so I don;t think that I could simply state that we believe it is an issue confined to this vendor as we were not paying sufficient attention to what they were doing to rule out other vendor supplied labor entirely.
              >
              > As far as general risk classification, the EDG is classified as a Mitigating System that supports Engineered Safety Features in hypothetical design base accidents. I suppose that I could winnow my EOCo down to other Mitigating Systems (there are in general, four others) that had vendor work performed that would have involved cotter pins. That might get me closer to something that I could get my arms around. Frankly, I'm not certain that I could make a convincing argument that the error would be confined to vendors however. A battle that I had to fight during the cause evaluation was that regardless of whether we consider proper installation of a cotter pin within the "skill of the craft," if the pin serves a function that if not properly completed could result in the inoperability of a required system, then we must call out that installation step and add measures such as independent verification to know that it was completed.
              >
              > As far as past failures, my internal OE search turned up a few cases of missing cotter pins on important safety systems at our site, but only ~5. My external OE search, however, turned up lots of examples (62 very similar cases) on lots of systems. It was the OE search that left me with the conundrum regarding the means to convincingly narrow my target population down to a manageable size.
              >
              > I do like the idea of using the vendor performed work as a starting point, and then looking at the work orders involving cotter pin replacement, confining that to work on systems classified as mitigating systems. At least this would allow us to begin the search by doing desk review first. We are entering a refueling outage soon, so we could perform inspections on most identified cases if I move quickly.
              >
              > Thanks for the great ideas. I guess that I should have gotten there on my own, but was overwhelmed by the external OE population suggested.
              > Have a great day
              > Judd
              >

            • Judd Sills
              Kay- Let me begin my response with an apology. I forgot to respond to this yesterday evening, and saw it again in today s posts, so please forgive me for
              Message 6 of 11 , Feb 5, 2013
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                Kay-
                Let me begin my response with an apology. I forgot to respond to this yesterday evening, and saw it again in today's posts, so please forgive me for forgetting to reply.

                Your question starts out with a general question about targets in connection to the extent of condition questions that I had asked last weekend. I can only speak for myself, and perhaps folks trained similarly, but the concept of target begins when we initially write our problem statement for the cause evaluation. I think that the object-defect terminology is relatively widely used in nuclear power, as I have seen it used at many nuclear power plants. You're probably quite correct about condition having a slightly different context in different types of investigations. For myself, "condition" is not the same in my mind as the "defect," though I do take "defect" to be part of my "condition." I don't know if that makes any sense, but to me, the condition is a bit bigger than just the defect or gap, and is more closely related to my problem that I am investigating.

                When I write my problem statement, it is, at least in my world, a three-part process. The first part is the identification of the requirement, standard or object that the analysis applies to. For an equipment problem, I'm generally going to find myself looking at the object that has in some way been acted upon. So, to go to my example from the weekend, I was looking at an impact upon my Class 1E Emergency Diesel Generator (EDG) on the A train of the redundant system. The second part comes when I am looking at the gap, defect or deviation that occurred. So for my example, the defect was the missing cotter pin, a specific type of fastener. The third part of my problem statement is to identify the actual or potential consequences of my gap, defect or deviation. So, for my situation, my object was a critical plant component, the emergency diesel generator, and the defect was the missing cotter pin, a fastener, and my consequence was that my emergency diesel generator was classified as inoperable in that it could not under all conditions be relied upon to perform its design function. So, when I go to performing my Extent of Condition, I am carrying this object-defect concept directly to that process.

                Extent of Condition is directly related to the "fundamental problem" associated with the problem statement, so to perform the assessment I have to go back to my problem statement. Extent of Condition (EOCo), again, in my world, is a two-step process. Initially, I've discovered a problem, in this case an EDG (my object) that has a missing cotter pin (my defect) resulting in a determination that the EDG is inoperable (the consequence). My first part of my EOCo is to immediately look for the same defect on the same equipment. So I did an EOCo to look for the same defect on the other train of my class 1E EDGs. As I get deeper into my analysis, I start to learn more about how the defect might have occurred and can begin to think about the potential for transportability of the defect to other objects. Hence, when I'm preparing my report, I have to broaden my question about the Extent of Condition tempered by what I now know about the problem that occurred; my second look at Extent of Condition. The question to be answered now is "Am I at risk of experiencing the same or similar consequence as the event that triggered the evaluation because the same conditions exist elsewhere in the plant?" As I was taught, there is a systematic way that I have to work through the question. I've already tackled what is called the "Same-Same" side of this question when I initially looked at my other train EDG for the same problem or defect.

                As I was taught, discussions of Extent of Condition are sufficiently broad when they include the Same-Same, Same-Similar, and Similar-Similar evaluation method. Other stations use the same method and instead of using the word "similar," use the word "different" in its place. Regardless of the vocabulary, the methods are the same. This method can be documented in a text-based format, or the evaluation logic can be illustrated via a "same-similar matrix" table format. I typically do it in a text format, but a 2 x 2 table can visually show you the blanks you're trying to fill-in, where on the rows I'm looking at my objects (same or similar) and on the columns, I'm looking at my defect (same defect, cotter pin, or similar defect other similar fasteners).

                So to carry this out in application, when I was asking my question to the group, I was trying to find a way to reasonably constrain my similar "target" population that my "defect" might possibly occur in. My initial thought was that it might be any safety related component that employs cotter pin fasteners. That was a very large amount of plant equipment, and a lot of research would have to be done simply to identify what that population was. With the help of the group and perhaps less caffeine, I was able to get a better scope on my similar "targets."

                I hope that covers what you wanted to hear more about. I'm sure that other industries and perhaps other nuclear power plants have slightly different ways of approaching this part of the evaluation. We are trying to respond to the example you provided from Inspection Procedure 95002 with what we are doing, so that we can be sure that we are sufficiently broad enough to withstand regulatory evaluation of our cause evaluation.

                Thanks very much
                Judd Sills
              • Kay Wilde Gallogly
                Judd, Thank you for the discussion. Kay From: Root_Cause_State_of_the_Practice@yahoogroups.com [mailto:Root_Cause_State_of_the_Practice@yahoogroups.com] On
                Message 7 of 11 , Feb 5, 2013
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                  Judd,

                   

                  Thank you for the discussion.

                   

                  Kay

                   

                  From: Root_Cause_State_of_the_Practice@yahoogroups.com [mailto:Root_Cause_State_of_the_Practice@yahoogroups.com] On Behalf Of Judd Sills
                  Sent: Tuesday, February 05, 2013 3:39 PM
                  To: Root_Cause_State_of_the_Practice@yahoogroups.com
                  Subject: [Root_Cause_State_of_the_Practice] Re: Extent of Condition - How far is reasonable

                   

                   

                  Kay-
                  Let me begin my response with an apology. I forgot to respond to this yesterday evening, and saw it again in today's posts, so please forgive me for forgetting to reply.

                  Your question starts out with a general question about targets in connection to the extent of condition questions that I had asked last weekend. I can only speak for myself, and perhaps folks trained similarly, but the concept of target begins when we initially write our problem statement for the cause evaluation. I think that the object-defect terminology is relatively widely used in nuclear power, as I have seen it used at many nuclear power plants. You're probably quite correct about condition having a slightly different context in different types of investigations. For myself, "condition" is not the same in my mind as the "defect," though I do take "defect" to be part of my "condition." I don't know if that makes any sense, but to me, the condition is a bit bigger than just the defect or gap, and is more closely related to my problem that I am investigating.

                  When I write my problem statement, it is, at least in my world, a three-part process. The first part is the identification of the requirement, standard or object that the analysis applies to. For an equipment problem, I'm generally going to find myself looking at the object that has in some way been acted upon. So, to go to my example from the weekend, I was looking at an impact upon my Class 1E Emergency Diesel Generator (EDG) on the A train of the redundant system. The second part comes when I am looking at the gap, defect or deviation that occurred. So for my example, the defect was the missing cotter pin, a specific type of fastener. The third part of my problem statement is to identify the actual or potential consequences of my gap, defect or deviation. So, for my situation, my object was a critical plant component, the emergency diesel generator, and the defect was the missing cotter pin, a fastener, and my consequence was that my emergency diesel generator was classified as inoperable in that it could not under all conditions be relied upon to perform its design function. So, when I go to performing my Extent of Condition, I am carrying this object-defect concept directly to that process.

                  Extent of Condition is directly related to the "fundamental problem" associated with the problem statement, so to perform the assessment I have to go back to my problem statement. Extent of Condition (EOCo), again, in my world, is a two-step process. Initially, I've discovered a problem, in this case an EDG (my object) that has a missing cotter pin (my defect) resulting in a determination that the EDG is inoperable (the consequence). My first part of my EOCo is to immediately look for the same defect on the same equipment. So I did an EOCo to look for the same defect on the other train of my class 1E EDGs. As I get deeper into my analysis, I start to learn more about how the defect might have occurred and can begin to think about the potential for transportability of the defect to other objects. Hence, when I'm preparing my report, I have to broaden my question about the Extent of Condition tempered by what I now know about the problem that occurred; my second look at Extent of Condition. The question to be answered now is "Am I at risk of experiencing the same or similar consequence as the event that triggered the evaluation because the same conditions exist elsewhere in the plant?" As I was taught, there is a systematic way that I have to work through the question. I've already tackled what is called the "Same-Same" side of this question when I initially looked at my other train EDG for the same problem or defect.

                  As I was taught, discussions of Extent of Condition are sufficiently broad when they include the Same-Same, Same-Similar, and Similar-Similar evaluation method. Other stations use the same method and instead of using the word "similar," use the word "different" in its place. Regardless of the vocabulary, the methods are the same. This method can be documented in a text-based format, or the evaluation logic can be illustrated via a "same-similar matrix" table format. I typically do it in a text format, but a 2 x 2 table can visually show you the blanks you're trying to fill-in, where on the rows I'm looking at my objects (same or similar) and on the columns, I'm looking at my defect (same defect, cotter pin, or similar defect other similar fasteners).

                  So to carry this out in application, when I was asking my question to the group, I was trying to find a way to reasonably constrain my similar "target" population that my "defect" might possibly occur in. My initial thought was that it might be any safety related component that employs cotter pin fasteners. That was a very large amount of plant equipment, and a lot of research would have to be done simply to identify what that population was. With the help of the group and perhaps less caffeine, I was able to get a better scope on my similar "targets."

                  I hope that covers what you wanted to hear more about. I'm sure that other industries and perhaps other nuclear power plants have slightly different ways of approaching this part of the evaluation. We are trying to respond to the example you provided from Inspection Procedure 95002 with what we are doing, so that we can be sure that we are sufficiently broad enough to withstand regulatory evaluation of our cause evaluation.

                  Thanks very much
                  Judd Sills

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