You can analyze failures that are reported against assets with the Failure History and Failure Analysis pages. The Failure History page displays detailed failure data, reported at the work order level. The Failure Analysis page aggregates failure data, based on the user-selected View By and displayed measures, such as Mean Time Between Failures (MTBF), and Mean Time To Repair (MTTR).

The three main measurements for asset maintainability and reliability are:

1. Mean Time Between Failures (MTBF): the average elapsed time between failures. MTBF is the duration in days between an asset's two failure dates, and is a reliability metric indicating how often an asset fails.

2. Mean Time To Repair (MTTR): the average time between when an asset fails (reported failure date) and when it is repaired to its normal operating condition (actual work order completion date). MTTR is a maintainability metric, indicating how fast repair is completed after a failure is reported.

3. Mean Time Between Repairs (MTBR): the average duration when an asset is in acceptable functional condition. The calculation is as follows:

   MTBR = MTBF - MTTR

   To analyze failure history information:

1. Navigate to the Failure History page (Failure Analysis tab > Failure History sub-tab).

2. Enter an Asset Number (or Rebuildable Serial Number).

3. Optionally enter a range of failure reporting dates.

4. If there is a Primary Failure Meter specified for the Asset, its readings automatically appear in the Search Result table.

   However, you can select any Required meters that are associated with the asset from the Display Readings from Meter list of values, to have the selected meter's readings appear in Failure History. This field is enabled only for the Simple Search, with a specified Asset Number.

5. Click the Go button.

   Additional Information: When calculating Mean Costs to Repair, all work orders that are associated with the failure results are included, if their costs are in the same currency. An asset can move between organizations if work orders have multiple currencies. All work order costs that are expressed in a currency that is different than the current maintenance organization's primary currency are excluded. A warning icon appears, informing you that there are repair costs that are not included because they are not in the current maintenance organization's currency.

   To analyze failure information:

Based on your search criteria, work order failure data is filtered for analysis. The View By selection determines how the failure data is aggregated for the MTBF, MTTR, and Mean Cost To Repair calculations. If there is a Primary Failure meter or if a Required meter is selected, the Mean Readings Between Failures are also calculated. You can compare MTBF, frequency, and MTTR calculations by Asset Number, Asset Group, Asset Category, or Failure.

1. Navigate to the Failure Analysis page (Maintenance Super User: Failure Analysis tab > Failure Analysis sub-tab).

2. Optionally enter an Asset Number (or Rebuildable Serial Number).

3. Optionally enter an Asset Group (or Rebuildable Item).

4. Optionally select an Asset Category of the selected Asset Group/Rebuildable Item that is assigned to the current organization

5. The Include Children option indicates whether children assets should also be included within the inquiry results, even if they do not fit the search criteria.

6. Optionally select a View By value. You can view failure information by Asset Number, Asset Group, Asset Category, or Failure Code.

   Note: Use Advanced Search if you want to search by other criteria such as Area. You cannot add additional View By values.

7. Optionally select a Display Readings from Meter value to display meter readings from a non-primary meter.

   Meters that are associated with the selected asset, having the Required check box selected, and that are identified as a non-primary meter, are available for selection. By default, readings from the primary meter, if it exists, appear. This field is enabled only for the Simple Search, with a specified Asset Number and if you View By Asset Number.

8. Optionally select a failure code to further narrow your failure results by code.

9. Optionally enter a range of failure reporting dates.

10. Click the Go button. The number of failure occurrences appear. A link from the Failure Count value provides a drill down to the Failure History information.