In RCM, effects refer to the outcomes that result from the failure of an asset. In the 7 Questions, effects represent the question What happens when a failure occurs? Analyzing the effects of failure is a critical step in the RCM methodology to determine the significance and impact of potential failures on safety, environment, operations, and overall system performance. Understanding these effects helps prioritize maintenance activities and develop appropriate maintenance strategies.

Effects should be captured by assuming that there is no maintenance strategy in place (describe what would happen without intervention).

To help the analysis team remain consistent when defining effects, they are often categorized into layers:

1. Local/Primary/Functional Effect: These are the direct consequences of a failure on the intended function or performance of the asset (or component). Local effects are concerned with how the failure affects the ability of the asset/component to perform its designated task. For example, if the function of a pump is to maintain a certain pressure in a system, the local effect would be a loss of pressure.
2. Secondary/Higher/End Effects: A complex asset consists of a hierarchy of sub-systems and components. This complex asset will itself serve a larger system. While the local effect is concerned with the component that provides the specific function under consideration, the higher effects are concerned with how that loss of function affects the (sub-)systems the component serves. Secondary/higher effects are the indirect consequences of a failure that may impact safety, environment, operations, or other aspects of the wider system. The hierarchy of the complex system/asset can be reflected by such effects, producing a reflective hierarchy of effects: Local (component) → Higher (sub-system) → End (system). Higher effects may not be immediately apparent but can have significant consequences over time. For instance, the loss of pressure described above may lead to an operationally critical system failing, leading to operational downtime.
3. Hidden/Latent Effects: Hidden effects are those that are not immediately obvious or easily detectable. They may become apparent only under specific conditions or after a certain period. Identifying hidden effects is crucial to ensuring that potential risks are thoroughly considered and managed.

When defining the effects you should consider:

• the ability to detect that the failure has occurred (evidence of failure)
• potential impact to safety
• potential impact to the environment
• potential impact to operations
• physical damage to assets
• what must be done to restore the function of the system

By systematically analyzing the effects of failures, RCM practitioners can better understand the impact of failure and prioritize maintenance tasks. This helps in developing targeted maintenance strategies to mitigate or prevent failures that could have significant impacts on safety, environmental compliance, and overall system performance.