What type of maintenance is defined as "unscheduled" in the 3-M context?

In the context of the 3-M System, "unscheduled" maintenance is defined as maintenance that occurs due to unexpected failures. This type of maintenance is not planned or scheduled in advance; rather, it arises in response to equipment malfunctions or breakdowns that were not anticipated. Unscheduled maintenance is critical in ensuring that systems remain operational and can include repairs and troubleshooting efforts that address immediate issues affecting equipment performance.

Understanding the nature of unscheduled maintenance is essential for effective maintenance planning and resource allocation. It highlights the importance of having contingency measures in place and the need for swift action to minimize downtime and maintain operational readiness. This is in contrast to scheduled maintenance, which involves regular, planned tasks designed to prevent failures from occurring in the first place.