The Seven Basic Questions

An RCM process uses a structured framework to ask the following questions about the selected asset in its operating context:

• What are the functions and the associated performance standards of the asset?
• In which ways does it fail to fulfil its functions?
• What causes each functional failure?
• What happens when each failure occurs?
• In what way does each failure matter?
• What can be done to prevent each failure?
• What should be done if a suitable preventive task cannot be found?

Briefly, these questions entail detailed analysis of the following areas;

• Functions - Defining the Functions and required performance standards of each asset in its operating context & defining the performance standards that are desired from each asset.
• Functional Failures - Establishing the Functional Failures that apply to each Function. A Functional Failure is defined as the inability of an item or component to meet its desired performance standards.
• Failure Modes - Determining the Failure Modes that cause each Functional Failure. Failure Modes are the engineering reason why a component or item fails. RCM concentrates on determining the root cause of failure.
• Failure Effects - Recording the Failure Effects, i.e. documenting what would happen if the Failure Mode occurs.
• Failure Consequences - Categorising the failure consequences of each Failure Mode by considering how much the failure matters. An RCM process classifies failure consequences into four groups:
• Hidden failures - In themselves have no direct consequences but expose the organisation to the risk of other (often serious) failures. Hidden failures are generally of protective functions.
• Safety or Environmental consequences - Where a failure could hurt or kill someone or lead to a breach of an environmental standard or regulation
• Operational consequences - Where a failure affects output, product quality, operating costs, or customer service
• Non operational consequences - Where the only cost associated with the failure is the direct cost of repair.