5. Critical Item Analysis

The Critical Item Analysis is an editor which is used to generate a list of items based on a set criticality method and value. The editor consists of four sections:

1. Analysis Options
2. Criticality Thresholding
3. Top Critical Items
4. Critical Items

To open Critical Item Analysis:

• Select Analyses > Critical Item Analysis from the main menu

5.1 Analysis Options Section

This section of the editor is used to set the End Effect and Propagation type used for the analysis.

To set these options:

1. Select the End Effect icon to open the Select an End Effect dialog
2. Select an item from the tree diagram
3. Select OK to close the dialog and set the End Effect
4. Select the drop-down menu for Propagation Type and select either FCM or Bond

5.2 Criticality Thresholding Section

This section of the editor is used to select the criticality measure and value used to set the threshold used in the analysis. The types of filters which can be used depend on the Criticality Profile set in Analysis Options. Selecting Calculate runs the analysis and generates a list of critical items. The items which appear in the Critical Items section are those which meet each of the thresholds for the desired filters.

To complete this section:

1. Select the button to open the Critical Item Filters window
2. Tick the boxes of the filters that are to be applied to the current profile
3. For filters with boxes ticked, set the threshold to the desired value

Once the calculations have been completed, the Top Critical Item and Critical Items sections will display items that have met the criticality threshold criteria.

5.3 Top Critical Items Section

This section consists of a bar chart which displays up to 5 items that have been classified as critical (i.e. exceeded the Threshold value in the Criticality Threshold section). The graph consists of individual bars for each critical item (x-axis) and their corresponding criticality values (y-axis).

To export this chart:

1. Select the export icon
2. Specify the file name and file path to save an image (PNG) of the bar chart

5.4 Critical Items Section

The Critical Items section consists of a table which lists the critical items shown in the Top Critical Items chart and information about each item. This information includes:

• Item Display Name
• Parent Item
• Item Number
• Replaceable designation (LRU or SRU)

The user can select Apply to Model to assign the Critical icon to all items in the table. This critical icon is displayed under each FBD in the system model editor.