Hi all, I think it depends on how you define criticality. Could be production, safety, environment and so forth.
For example, when we do an RCM we examine the functionality and sometimes away from the clear primary function and the usually clearly defined production / safety functions for secondary functions it isn't always so obvious, and some digging and thinking is required.
The function and purpose within the operating context eventually does come out, what this has taught me is that there is always a purpose & reason for the equipment, otherwise it wouldn't be there, I just didn't know what it was.
From that I would say that everything is critical (but just to different degrees and for different reasons) because it was designed, it was purchased, it was installed, it was part of CAPEX, It adds weight to the platform, it has operating cost, its part of OPEX, it will need to be deconstructed and removed, it has ABEX (abandonment cost) etc etc.
Therefore, because it took some effort to get a piece of equipment to the platform or plant, I'd assume that it was necessary. So, in a sense everything is critical it's just that some are more critical than others.
I'm wary of identifying a proportion that are "critical" because that then suggests the remaining equipment aren't and that can lead to across the board maintenance cuts by criticality rather than considering what needs to be done.
If you find truly superfluous equipment because perhaps operations or context have changed then decommission or remove it. If its of such low criticality then question why it is there.
And of course have a great festive break, but most importantly - Stay Safe!
------------------------------
Mike Hobbs
Atkins Limited
Aberdeen
------------------------------
Original Message:
Sent: 12-12-2018 09:37 AM
From: Matthew Kern
Subject: What percentage of all assets, in a plant/site, should be classified as critical?
Mr. Eisenbise,
In order to answer this question we must first decide if we follow a risk type criticality (severity x frequency) or severity only criticality. I personally subscribe to the severity only as it tells us what the consequence of failure will be and, unless repurposed, should vary little over the life of the asset. Frequency, however, may and should change over time based on the competency of personnel, quality of procedures, variations in process, etc. The Norsok standard agrees with this but there are other standards which do advocate a risk based criticality.
In a simple example to the above, let's suppose I provide surgical lighting systems. My company owns 30 of these assets all operating in similar operating rooms with minimal or no redundancy due to space. The criticality of these systems would likely be high due to the consequence of failure. Trying to say that 20% of these lights, providing a near similar function, are more critical than the others doesn't pass the red-face test. They are all equally critical and it would be unreasonable for any standard to guide us to lumping 15 or 20% into a bucket of "critical"
If the purpose of the exercise is to guide us on priority we should instead temporarily assign a frequency of failure ranking to each asset to help guide us on where we might focus our training efforts, procedure efforts and the like. But as soon as we do these things the frequency, and thus risk, should be reduced on those assets.
In my opinion, we should be cautious to equate criticality with risk of which the latter is more dynamic. If we are looking for a prioritization tool we can assign a temporary risk with the awareness that risk should change if the actions we implement are successful in reducing the frequency of occurrence. Based on this stance, it would be misguided for any standard to tell us that a certain percentage of assets should be more critical than others.
------------------------------
Matthew Kern
Houston TX
Original Message:
Sent: 11-27-2018 11:30 PM
From: Michael Eisenbise
Subject: What percentage of all assets, in a plant/site, should be classified as critical?
Based on my experience, many plants identify about 15% to 20% of all assets as critical assets. One of the key RCM experts Anthony (Mac) Smith has often stated he feels that assets follow the 80/20 rule. He explains that 20% of all assets at a site should receive the most focus and receive a full classical RCM analysis.
Feel there are many opinions on what percentage of assets should be classified as critical. However, has anyone seen a standard or other reference that outlines what percentage of all assets should be classified as critical?
Or, has anyone ever seen a study published on this topic?
Any comments or suggestions you many have would be helpful.
Thanks in advance
------------------------------
Michael Eisenbise
Retired
BP
League City TX
------------------------------