Unplanned maintenanceFree guide to preventive maintenance
What is unplanned maintenance?
Unplanned maintenance is any maintenance task that occurs unexpectedly. It happens when there is no formal strategy in place to address a repair, replacement, or inspection before it’s needed. Unplanned maintenance is commonly the result of equipment failure that was not anticipated.
Unplanned maintenance vs. unscheduled maintenance
Although they sound similar and are often used interchangeably, unplanned maintenance and unscheduled maintenance have a few key differences.
Unplanned maintenance is maintenance that is totally unexpected. There's no plan in place to complete it. Unscheduled maintenance is maintenance that is planned, but is not scheduled for specific time and has not been assigned to a technician.
Maintenance can be planned and unscheduled, but not the other way around. Here's an example of that: You know that a conveyor system needs maintenance every 50 hours of operation. You know how long maintenance will take, what tasks need to be completed as part of that maintenance, how much it will cost, and what parts you will need for the job. In other words, you have a plan for it. However, you don't know when the system will hit 50 hours of use. It might be in one week or in three. In other words, it's unscheduled.
Types of unplanned maintenance
There are three main types of unplanned maintenance:
Reactive maintenance is any maintenance done to fix equipment after it breaks down unexpectedly. Repairs are done as a reaction to the failure and haven’t been planned for. Reactive maintenance can also be called breakdown maintenance.
Corrective maintenance gets equipment working again after it stops operating properly. Corrective maintenance ranges from fixing a minor defect that’s causing an asset to run slowly, to repairs on a machine that has completely broken down. This type of maintenance corrects unforeseen problems that haven’t been planned for.
Opportunistic maintenance takes advantage of an unexpected stoppage in production to perform preventive maintenance on equipment or assets. Because the stoppage was not scheduled, the corresponding maintenance is unplanned.
Examples of unplanned maintenance
Let’s say that an asset relies on a motor to operate properly. Because the motor has been so reliable, there’s no plan in place for when it fails. But one day, the unexpected happens and the motor breaks, causing production to stop. A technician must set aside everything in their schedule to fix the motor. There’s no time allotted to the job and no formal guidelines. Because maintenance is done in reaction to a problem, this is an example of reactive maintenance.
Think about an asset at your facility that undergoes regular preventive maintenance. There’s a plan to identify and fix small problems with this asset before they lead to failure. However, between PMs, an operator notices the asset isn’t functioning as it should be, which is affecting production. A technician now needs to repair the asset before the scheduled PM to correct the problem. Since the technician is doing unplanned work to correct a problem, this is an example of corrective maintenance.
Imagine you’re performing preventive maintenance on an asset and notice that another part of the machine is deteriorating. You take the time to do some maintenance on that other part so it doesn’t cause failure in the future. Because this maintenance wasn’t planned along with the original work order and was identified during another task, this is an example of opportunistic maintenance.
Want to learn more about key performance indicators (KPIs) for maintenance excellence?
Read our "Advanced CMMS Metrics" e-book to find out how you can measure them with your CMMS software.Get your free e-book
When to use unplanned maintenance?
Here are some situations when unplanned maintenance can be an effective part of a balanced maintenance strategy:
- When equipment is not designed to be repairable or is located where repairs are not possible
- When equipment is not production-critical and is quick, safe, and inexpensive to repair or replace
- When equipment is designed to be replaced at the end of its lifespan
- When failed equipment can be easily bypassed, or redundant systems are in place
It’s important to think about the impact of failure on specific assets when including unplanned maintenance in a broader maintenance strategy. A broken piece of equipment in one facility might not affect production or workers at all, but the same part might be crucial to staying productive and compliant at another facility. Unplanned maintenance should never be considered when the safety of people is at stake.
Unplanned maintenance can be a useful part of a broader maintenance strategy, but only if an organization has carefully assessed the equipment and assets involved, and understands the impact that an unplanned failure will have on production. However, steering clear from unplanned maintenance and toward a preventive approach is key to eliminating some of the biggest inefficiencies at your operation.