Concepts

Tasks

Settings

Defining the Problem

In the RCA window, the Definition view allows you to document the problem by entering a problem description and statement. You can add failures, review failure consequences, and augment the definition by attaching documents, photographs, and so on.

For a reactive analysis based on one or more failure records, the Consequences tab displays the result of the RCA evaluation. The Failures tab lists the original failures. You can add related failure records and evaluate failure consequences using these tabs.

Evaluating Failure Consequences

Using the Definition view, Consequences tab, you can evaluate the primary failure’s suitability for root cause analysis based on its criticality index. The evaluation produces one of these recommendations:

•	RCA not required

•	RCA recommended

•	RCA required

APM calculates the criticality index as follows:

Criticality Index = Consequence priority * Failure Severity *
Probability of Recurrence

Consequence Priority

During the evaluation, the team specifies whether the failure is evident or hidden. Then they determine the failure’s consequence priority by selecting severity values for the health and safety, environmental, and economic consequences. For example:

Note: If the failure references a failure mode, severity values are copied from the failure mode’s risk analysis to the failure’s Consequences tab.

APM calculates the consequence priority by multiplying the severity values by their weighting factors and then applying a rule to the result. For example, the following rule could assign a consequence priority of “Medium”.

Any of(Environmental, Economic, Safety) Is equal to 3.00

Rules can also include the failure record’s downtime and failure costs. The larger the consequence priority number, the greater its priority.

Criticality Index

The criticality index is calculated by multiplying the numbers assigned to the consequence priority, failure severity, and probability of recurrence. For example:

Recommendation

The failure’s evident/hidden value and its criticality index determine the RCA recommendation.

The recommendation is determined by the position of the criticality index value in the recommendation thresholds.

Updating the Failure Analysis Status

When you have completed the evaluation, you can change the failure analysis status to “Completed” or “Not required”.

The value is shown in the Failure analysis status box:

This topic explains how:

•	To Add Failures to an RCA

•	To Evaluate Failures for RCA

•	To Update the Failure Analysis Status

•	To Document the Problem

To Add Failures to an RCA

1.	In the RCA window, Definition view, select the Failures tab.

2.	Click Browse. The Browse Failures for RCA dialog lists failures with the status “RCA required” or “RCA recommended”. To view all failure records, select “Failures” in the configuration list.

3.	Select the failures to add to the RCA and click OK. The failures are added to the table. For example:

4.	By default, the first failure is designated as the primary one. You can select a different failure in the Primary failure list. The primary failure’s information is displayed in the Consequences tab. Its failure description is listed as the problem in the RCA diagram.

Tip: You can also view the failures’ consequence evaluations on the Failures tab. Select “Consequences analysis” from the list of configurations.

To Evaluate Failures for RCA

1.	Open the RCA, select the Definition view and the Consequences tab.

2.	Make sure that editing is enabled.

In the following example, failures have been added to the RCA. The primary failure has not been evaluated for root cause analysis. APM copied the downtime and failure costs and failure severity from the primary failure to the Consequences tab.

3.	Downtime and downtime costs are compiled from all downtime incidents that reference the failure. Failure costs are copied from the failure record. These costs can be used in the rules that determine the consequence priority. You can change this information, if necessary.

4.	In the Evaluation area, provide the information needed to arrive at a recommendation:

Setting Name

Description

Evident failure

Specify whether the failure is evident or hidden. A hidden failure’s effects do not become apparent to the operating crew under normal circumstances if the failure occurs on its own. Hidden failures are typically given higher priority for RCA because they often require failure-finding maintenance tasks.

Health and safety

Equipment failure can cause hazards in the workplace. Examples are extreme temperatures, noxious fumes, and the release of liquids that can kill or injure someone. Select a severity value from the list. Each option has a weighting and severity number that is used to calculate the consequence priority.

Environmental

There is an unacceptable risk that the effects of this failure could breach a known environmental standard or regulation. Select a severity value from the list. Each option has a weighting and severity number that is used to calculate the consequence priority.

Economic

The economic consequence of failure reflects the financial effect on assets and production. Labor and material costs associated with lost production and with repairing or replacing the damaged equipment are economic consequences. Select a severity value from the list. Each option has a weighting and severity number that is used to calculate the consequence priority.

Consequence priority

APM calculates the consequence priority by multiplying each severity value by its weighting factor and then applying a rule. For example, a consequence priority of “High” (with a score of 3) might have the rule: Any of(Environmental, Economic, Safety) Is equal to 4.00

Failure severity

The severity indicates the seriousness of the failure. For example: • Total: the asset’s performance has decreased to a point where the asset is no longer performing at its required level. The asset has completely failed. • Partial: the asset’s performance has decreased to a point where it is no longer performing one of its functions at the specified levels. The asset is still functioning. • Potential: a condition that has been noticed that would result in an actual failure if the problem is not resolved. The actual failure has not yet occurred. Potential failures are normally reported as the result of an indicator reading that has raised a warning alarm against the asset. To indicate its relative seriousness, each failure severity is assigned a number, which is used to calculate the criticality index.

Probability of recurrence

Probability of recurrence is used to quantify the likelihood of the failure happening again. Each probability is assigned a score, which is used to calculate the criticality index.

Criticality index

The criticality index is calculated by multiplying the numbers assigned to the consequence priority, failure severity, and probability of recurrence. The index is used to determine the recommendation.

Recommendation

The recommendation is based on the criticality index. Possible values are: • RCA not required • RCA recommended • RCA required • RCA evaluation not performed The recommendation is determined by the position of the index number in the recommendation thresholds, which are set in RCA settings. The default value is “RCA evaluation not performed”.

To Update the Failure Analysis Status

When the evaluation is complete, click the Tools menu, Failure Analysis, and then click one of:

•	Mark as Completed

•	Mark as Not Required

The value in the Failure analysis status box changes accordingly.

To Document the Problem

1.	In the RCA window, select the Definition view and the Problem tab.

2.	If a primary failure has been identified, its description and statement appear on this tab. You can enter or revise the problem definition and statement.

Tip: APM adds the problem description to the Problem node in the RCA diagram.

3.	Select the Photos tab to add inspection photographs. For more information, see Adding Inspection Photographs to Objects.

4.	Select the Attachments tab to add files, folder, notes, and URLs to the analysis.