In RCM, consequence refers to the impact or outcome that results from the failure of an asset. In the 7 Questions, consequences represent the question; In what way does each failure matter? Analyzing the consequences of failure is a crucial step in RCM to assess the significance and severity of potential failures.

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

Before assessing the consequence, we need to know if the failure will be observed during normal operation. If it is observable, it is an evident failure mode. If it is not observable during normal operation, it is a hidden failure mode. Hidden failures usually occur in protective functions. A protective function is one that protects another function or the operator. Examples include alerts & warnings, guards & shields and emergency shut-down systems. If your car dashboard warning light has failed, there will be no consequence, at least no direct consequence. It is essential to understand such failures, as they protect further functions which will have safety, environmental or operational consequences.

Consequences in RCM are typically categorized to provide a structured understanding of the impact and priority of failures.

These categories usually include:

1. Safety Consequences: Safety consequences involve the potential harm or risk to personnel or the public. Identifying safety consequences is crucial in RCM, especially for assets that have implications for human safety. Examples include the release of hazardous substances, fires, or explosions.
2. Environmental Consequences: Environmental consequences consider the impact of the failure on the surrounding environment. This may include pollution, contamination, or other adverse effects on ecosystems. Assets that pose environmental risks, such as chemical storage tanks, require careful consideration of these consequences.

   Note: safety and environmental consequences are often joined into a single consequence, as together they form the primary consequence of any failure.

3. Operational Consequences: These consequences pertain to the impact on the overall operation of the system or process. Operational consequences consider how the failure affects the efficiency, productivity, and continuity of operations. For instance, a failure in a critical machine might lead to production downtime or delays. Operational consequences usually involve a financial impact, such as losses due to downtime or reduced efficiency.
4. Non-operational / Economic Consequences: Non-operational (economic) consequences involve the direct financial impact of a failure, including repair or replacement costs (but do not include operational costs). These consequences are considered if none of the above are present. By understanding the non-operational cost of failure, we can determine if preventative maintenance is economically viable.

Analyzing consequences helps RCM practitioners prioritize maintenance tasks based on the criticality of the impact and determine the most appropriate maintenance strategies to prevent or mitigate these consequences effectively.