Asset Criticality Calculations

Asset Management Calculations used in Diamond Maps

The following calculations are used in determining End-Of-Life (EOL), POF, COF, and Risk.  The following steps occur in the order listed.  These steps occur whenever the user makes a change to any dependent field.  If you import new data into an asset management layer you may want to run the "Redo Calculations" tool on the Asset Management menu to assure that these calculations get performed on the newly imported features.

1. Calculate an age based EOL
2. Calculate a condition only based EOL
3. Calculate an age + condition based EOL (based on EPA CUPSS method)
4. Auto determine which physical failure method should be used
5. Select a single EOL value based on user selected failure mode
6. Calculate a COF score
7. Calculate a POF score
8. Calculate a Risk

Terms

EOL: End of Life - estimated year
REL: Remaining Effective Life - in years
COF: Consequence Of Failure - a score that measures of how bad it would be for a certain asset to fail.
POF: Probability Of Failure - a score that measures how probably it is that an asset will fail this year
PELC: Percent of Effective Life Consumed 
Risk: a single score that measures the combination of both COF and POF.  Risk = COF X POF

Detailed Description

A more detailed description of each step is included below

1. Calculate an age based EOL
   1. if the installYear or designYears values are not given then the ageBasedEol is set to blank and no calculation is performed. STOP
   2. ageBasedEol = installYear + designYear
2. Calculate a condition only based EOL
   1. a conditionFactor is set to .9, .7, .5, .2, or 0 depending on the condition text
   2. if the condition text is blank then the conditionEol is set to blank. STOP
   3. if the given conditionYear is blank then thisYear is used in its place
   4. REL = designYears X conditionFactor
   5. conditionEol = conditionYear + REL
3. Calculate an age + condition based EOL (ie. CUPSS method)
   1. A conditionFactor is set to 1.1, 1.05, 1.0, .9, or .8 based on condition text
   2. If the given condition text or install year are blank then the cupssEol is set to blank. STOP
   3. EOL = installYear + designYears
   4. REL = EOL – conditionYear
   5. If REL is negative then set REL=0
   6. REL = REL X conditionFactor
   7. cupssEol = conditionYear + REL
4. Auto determine which physical failure method should be used
   1. If the Auto calculate box is checked Diamond Maps will auto determine which physical failure mode should be used.  The following logic is used
   2. If a conditionEol was calculated above then select the Condition failure mode
   3. If conditionEol is blank but AgeEol was calculated then select the Age failure mode
   4. If a staff judgement value is provided and it is earlier than the Eol value auto selected above then select the staffJudgement mode
5. Select a single EOL value based on user selected failure mode
   1. The EOL associated with the users failure mode selection is determined and this EOL value is used in all further calculations below.
   2. No auto determination of failure mode is performed as user interacts with form.  That is to say that the EOL associated with the users selection is used even if one of the other failure modes has an earlier EOL.  However, when originally importing records from the FGDB, the failure mode is automatically set to which ever failure mode has the earliest EOL value.
6. Calculate a COF score (consequence of failure)
   1. The COF score is set to 2, 4, 6, 8, or 10 based on the COF text.
   2. If the COF text is blank, a value of 2 is used which corresponds to “insignificant.”
7. Calculate a POF score
   1. A redundancyFactor is set to 0 5, 9, or 9.8 per the Redundancy text
   2. REL = EOL( from step 5) – thisYear
   3. PELC = (designYears – REL) / designYears
   4. If PELC is negative then set to 0.  Happens in rare scenarios such as a future installYear
   5. POF = PELC X (10 – redundancyFactor)
8. Calculate a Risk
   1. Risk = COF X POF
   2. If Risk > 100 then set Risk = 100