Monthly Archives: June 2015

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Author: Ben Rowland

Surely if some is good, more is better? Like many things in life, there can be too much of a good thing when it comes to detail in an RCM study and finding the right balance can be tricky. Too little detail and you may miss things, too much and you could suffer from ‘analysis paralysis!’ B

So how do we know when we’ve ‘drilled down’ far enough to be thorough but not too far?

John Moubray summarised it nicely in his RCM 2 textbook:

“Failure Modes should be defined in enough detail for it to be possible to select a suitable failure management policy” (Moubray, 2007)

So what is a suitable failure management policy? The failure management policy is the approach chosen in order to mitigate the consequences of failure to an acceptable level.

Let’s consider two pumps; one is a large, complex gas compression pump and the other is a small air conditioning pump on a fork lift.

When trying to understand what the ‘suitable failure management policy’ is, it is necessary to take into account the ‘bigger picture’ of the equipment under consideration:

Function

What is the function of the machine? What is its purpose? Understanding this will help to understand the consequences of the failure, which in turn will help define the criticality.

Criticality

How critical is it if the failure occurs? Criticality is a product of the severity of the consequences of a failure multiplied and the frequency of occurrence.

In the case of large gas compression pump, a failure could result in product not being delivered, costing $1000’s per hour of downtime. Or for the forklift a/c pump it could be returning the forklift to be swapped for another in the fleet.

Repair vs. replace policy

Another aspect to consider is what is the corrective action? Is it feasible/cost effective to stock the spares and perform a repair activity in-situ, or to simply replace with a new unit?

For a large, expensive pump it would be more expensive to replace the entire unit than to replace a worn seal. Whereas for a small a/c pump it would be more cost effective to discard it and replace with a new one.

Hidden failure

Are the failures evident in normal operation, or do they require fault finding to be performed? Can the seals be seen to check for signs of leakage?

Operating context

How accessible is the equipment? Is scaffolding required? Is the plant required to be shut down? Does the equipment need to be partially dismantled e.g. removing guards etc? Is there any redundancy in place? Is the equipment in a remote location, or a challenging environment?

These are just some things to consider when considering what a ‘suitable failure management policy’ might be for your particular piece of equipment.

Back to our pump examples;
For the large gas compression pump, it is expensive to replace, critical if it fails and is accessible for in-situ repair during scheduled shut downs. In this case the FMEA would be far more detailed, including several failure modes, each with its own inspection or planned maintenance tasks, which would combine to form the ‘Failure Management Policy’ for this pump.

Image 1 How much detail

For the small AC pump on a forklift, let’s say it’s inaccessible for inspection, not critical if it fails and would be replaced rather than repaired. Our FMEA might only include a small number of failure modes, such as ‘Seal worn’, ‘Impellor worn’ and ‘Motor burnt out’ and our corresponding ‘Failure Management Policy’ would be ‘No scheduled maintenance’ and the corrective action would be to ‘Replace AC pump’.

Image 2 How much detail

In conclusion, it can be a challenge to know how much detail to go into when performing a FMEA analysis, but the aim is to go into enough detail to determine a suitable failure management policy. Considering the ‘bigger picture’ of the equipment you are analysing will help guide you as to the level of detail required.

alternate realitiesMuchas veces nuestras diferencias pueden ser una fuente de conflicto o confusión, pero en este artículo me gustaría explorar cómo pueden aprovecharse para resolver problemas en lugar de crearlos.

“Todo va a estar bien si tú lo haces a mi manera.” En algún momento todos hemos probablemente dicho o pensado algo como esto. O tal vez usted lo ha oído de alguien más (muy probable que de su pareja). ¿Cuál es el sentimiento base o cual es el problema aquí? Lo que realmente estamos diciendo es: “Si todo el mundo es igual que yo y pensamos de la misma manera, todo va a estar bien.” Desde luego que esto es imposible. La investigación en neurociencia nos dice que no hay dos cerebros que sean exactamente iguales, y para citar un artículo de Scientific American sobre este tema, “… si el aparato que detecta el mundo difiere entre dos individuos, entonces la experiencia consciente de los cerebros conectados a sus sensores, por tanto, no puede ser la misma”.

Los buenos solucionadores de problemas deben ser conscientes de esto para que no caigan en la trampa de suponer que todo el mundo sabe lo mismo, o que todo el mundo interpreta la información de la misma manera. Yo estaba cambiando los canales de televisión un día y vi un espectáculo interesante de gemelos siameses que comparten un solo cuerpo y la mayoría de los órganos, pero tienen cabezas completamente separadas (y por lo tanto sus cerebros). Cuando el entrevistador plantea una pregunta, cada gemelo respondió a su vez con diferentes respuestas. Esto provocó un desacuerdo entre ellos.

Estas dos personas compartían una crianza idéntica, estaban expuestos  a la vida y a los factores ambientales como cualquier humano, y sin embargo, todavía pensaban diferente. Si eso no te convence de que es imposible que dos cerebros distintos puedan compartir la misma perspectiva, entonces, ¡no estoy seguro de que lo hará!

He aquí un ejemplo de cómo dos personas pueden estar teniendo una conversación sobre lo mismo tema y sin embargo no estar hablando de lo mismo en absoluto. Durante un ejercicio común en una de mis clases, comenzó una discusión entusiasta acerca de los como limpiar los peces. Todos, excepto un estudiante brillante parecía estar en la misma página. Todo el mundo tenía la sensación de que esta persona estaba siendo difícil, pero algo dentro de mí recordó que debía obtener más información. Después de un par de preguntas de sondeo descubrimos que no teníamos el mismo punto de vista sobre el tema. Esta persona nunca había estado pescando y no entendía que “limpiar los peces” implicaba destriparlos y prepararlos para el consumo. Ella no podía entender el ejercicio debido a que su punto de vista de la limpieza era lavar y en general limpiar el exterior de algo, por lo que decía: ¿¡que tiene que ver un cuchillo con todo esto!?

Una observación más personal para respaldar este tema es una discusión que tuve con colegas acerca de la “Jerarquía de Controles” (se muestra en la foto a continuación como referencia).

Un colega dijo que el otro debe entender este concepto ya que tiene una formación en ingeniería, y todos los ingenieros sabrían esto. Tuve que informarles que yo también tengo una formación de 30 años en ingeniería, mantenimiento y confiabilidad, pero en realidad nunca había estado expuesto al término tampoco. Así que una vez más, la situación imposible de la perspectiva de cada uno es idéntica vuelve a relucir.

Pyramid_ARMSColours_SP

Mientras que hace su Análisis Causa Raíz, debe mantener el tema de la perspectiva en mente. Asegúrese de formular la definición del problema para que cada perspectiva tenga la oportunidad de ser escuchada, y que el problema es un reflejo de todas las perspectivas del equipo. Mientras se hace el Análisis Causa Raíz, talvez algunos no alcen la voz en la reunión, así que como Facilitador es su trabajo hacer que dichas personas externen su perspectiva y asegurarse entonces que sean escuchados.

En mi experiencia, puede tener un impacto significativo en la comprensión de una causa particular para el equipo. Aunque a veces lo que anhelamos es que todo el mundo vea las cosas exactamente como nosotros, teniendo en cuenta las realidades alternas de los demás es clave para construir una imagen más completa de su problema, lo que le permite encontrar la mejor solución.

Author: Kevin Stewart

RCAInvestigationScoreSheet_Mock-up

Audit is defined in the Merriam-Webster dictionary as:  “a methodical examination and review.” When we talk about auditing your Root Cause Analysis (RCA) investigations, we mean just that — a methodical examination and review. This is easier said than done, especially without some sort of standard to gauge against. If we establish a standard by which we gauge the quality of an RCA, the audit then becomes a simple matter of checking the RCA against the accepted standard and then determining how well it meets that standard. This post is all about helping you establish a standard, and we’ll even give you a free score sheet template to get you started.

Could you have the worst-looking RCA in the world and meet none of the criteria, but have an effective solution that: 

  • prevents reoccurrence,
  • meets our goals and objectives,
  • is within our control, and
  • doesn’t cause other problems?

Sure, and it is hard to argue with success. I doubt anyone would say: “Even though this solution will prevent the problem from recurring, it comes from an RCA that doesn’t meet our stringent, high-quality metrics so we can’t use it.” This scenario is entirely possible, though the odds of it are unlikely. If we have a set of measures to check an RCA against to ensure it meets some quality standards, the probability of an effective solution coming from that RCA is greatly increased. 

So what characteristics of an RCA are important?

Here are some questions to consider: 

(If you need a refresher on some of these points, I’ve included the relevant page numbers from the eBook “RealityCharting™: Seven Steps to Effective Problem-Solving and Strategies for Personal Success” by Dean L. Gano.)

  • Do the causes pass the noun-verb test? (page 83)

noun-verb_relationships

  • Do the causes have a lot of unnecessary words or descriptors?
  • Do the causal elements pass all logic tests? (page 108)
    • Space-Time Logic Check 

      • Do the causes of this effect exist at the same time? 
      • Do the causes of this effect exist in the same place?
    • Causal Logic Check
      • If you remove this cause, will the effect still exist?
        If the answer to this question is no, then the cause is necessary for the causal relationship and should stay on the chart. If the answer is yes, it should be removed or repositioned.
  • Are there any rule violations? If so, what are they and do they pass the minimum standards? Rules to be included are:
    • Are any of the cause boxes empty?
    • Are there any unconnected causes floating around in the chart?
    • Has each cause been identified as an action or condition?
    • Does each effect meet the 2nd principle (causes exist in an infinite continuum – there is an action and a condition for each effect)?
    • Have all conjunctions been eliminated? Remember that “and” is often interpreted to mean “caused,” which can leave too much room for misunderstanding and error. (pages 67-68)
    • Does each cause have the appropriate supporting evidence to justify its inclusion in the chart?
    • Does each branch have some type of stop identified for it? Below are the five potential stops: (pages 88-89)
      • Question Mark – more information needed; an Action Item is created.
      • Desired Condition – there is no need to keep asking why.
      • Lack of Control – something over which you or your organization have no control, for example “laws of physics.”
      • New Primary Effect – a separate analysis is required.
      • Other Cause Paths More Productive – continuing down this path would be a waste of time.
  • Does the solution matrix fall into a typical mix such as:

AuditingYourRCA_Graphic

  • Have the solutions been judged against a standardized set of criteria with standard ranges to minimize the possibility of favorite solutions being chosen? (page 118-120)
  • Has each solution been assigned to a team member and given a due date?
  • Does the chart meet all of the four principles of causation? (page 36)
    • Causes and effects are the same thing.
    • Causes exist in an infinite continuum.
    • Each effect has at least two causes in the form of actions and conditions.
    • An effect exists only if its causes exist in the same space and time frame.
  • Does the problem definition establish a clear dollar value significance that will let management make informed choices and approvals?
    • If a dollar value is not appropriate (safety near miss or potential fatality) does the problem definition establish a significant value?
  • Have all of the action items been resolved? (Action items can include areas where more information is needed, there are evidence issues, or any manually entered items need to be resolved and deleted.)

The next step in developing an audit is to generate a checklist that your RCA will be gauged against.

This list can come from the items above, your own list, or a combination of the two. Once you have a list of items to audit against, you need to generate a ratings scale. This can be a pass/fail situation or a scale that gives a rating from 0 to 5 for each item. This can allow you to give partial credit for some items that may not quite meet the full standard.

Develop a score sheet with each item listed and a place to put a score for each one. Don’t forget to leave a space for notes from the reviewer to explain the reasons for partial credit. It’s handy to add some guidelines with each item to give the reviewer a gauge to score the item against. A sample of such guidelines might look like:

0 = Does not exist
1 = Some are in place but not correct
2 = Many are in place and some are correct
3 = All are in place but only some are correct
4 = All are in place and most are correct
5 = All are in place and correct

With guidelines like these easily available as a reference on your score sheet, it helps ensure consistency in the scoring, especially if multiple people will be scoring an RCA.

Now all you have to do is review an RCA against your list, score it, and have some sort of minimum for passing.

This will ensure that each RCA is measured against a consistent standard that can be repeated by multiple people, though there will always be differences if multiple people are auditing RCAs. Differences can be minimized by either having only one person doing the audit or calibrating the audit, or by bringing all personnel together and scoring several as group so that all auditors understand the scoring nuances.

While I’ve provided a pretty thorough list of what to check for when auditing an RCA, my experience is that an RCA can meet all of the requirements above and still have some issues. The biggest one is that the logic may be correct but the causes may not, so the RCA can pass the tests but it won’t actually fix the issue. The fact is, humans are involved and we make mistakes. Sometimes the errors can be caused by inexperienced investigators that need more practice. Other reasons for error are some of the filters that we talk about, such as time constraints, preconceived notions or biases, language issues, etc. This means that there is still a component that needs to be reviewed by someone for general integrity and for things that a computer just can’t look for. This person can be an external corporate person, a contractor, or an internal resource.

RealityCharting™ has tools that are available to the reviewer to assist them in critiquing the analysis such as rules check, action item report, causal element view, and most importantly there is a dashboard.

 

RCAInvestigationScoreSheet_Mock-up

 

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To assist you in creating your RCA score sheet, we’re offering a free template.