Maintenance analysis has changed a lot over the last decade or so. New tools and technology have increased our ability to collect and interpret data. It’s enabled us to make informed decisions that wouldn’t have been possible 10 years ago.
But if our understanding of maintenance analysis has changed, why do we still rely on the same handful of metrics we did 40 or 50 years ago?
Metrics like overall equipment effectiveness (OEE) and mean time to repair (MTTR) dominate almost every list of go-to industry measurements. But experts agree that they’re flawed. Not only are these traditional metrics prone to bias and inaccuracy, but they also often don’t have a purpose. And when data doesn’t have a purpose, you can’t use it to make key decisions, like whether to hire an extra technician or increase the frequency of a task.
That’s why we’ve put together 10 useful metrics you won’t see on any other list and some tips for how to use them to improve your maintenance program.
10 maintenance metrics for better maintenance analysis
#1 – Time spent supporting production
What is it?: The total time that the maintenance team spends on production-focused activities. Usually measured weekly, monthly, or quarterly.
How can you use it?: Everyone has to pitch in to complete a big order once in a while. But when once in a while turns into every day, maintenance suffers. This metric helps you catch an unhealthy backlog before it happens and reallocate resources to prevent it. It also helps you advocate for a higher headcount on your team or increased training budget to help production staff learn minor maintenance tasks.
#2 – Follow-up work created after inspections
What is it?: The number of corrective work orders created from routine inspections. Usually measured monthly, quarterly, or annually.
How can you use it?: There are many different ways you can use this metric for maintenance analysis. You can sort it by machine, shift, or site to get insights into how your assets or team are performing. But the most useful is by task.
It’s a good sign when regular preventive maintenance includes follow-up repairs. It means your schedule is accurate and that you’re preventing bigger problems. It allows you to flag common repairs and build processes to make them more efficient. For example, you can create parts kits for quicker access.
If the failed inspection percentage is low, you can increase preventive maintenance intervals. This will reduce the amount of time and money spent on tasks without increasing risk.
#3 – Cost of follow-up maintenance vs expected cost of total failure
What is it?: A comparison between the cost of corrective maintenance (i.e. labor and parts) and the cost of asset failure if maintenance is not done (i.e. lost production, labor, and parts).
How can you use it?: Use this type of maintenance analysis to plan your maintenance strategy. For example, if regular inspections cost you more than failure, you can likely go with a run-to-failure approach for an asset over a preventive one.
You can also use this metric to prioritize tasks and backlog, and figure out how to allocate your budget.
#4 – Cost by maintenance type
What is it?: The total cost of maintenance (i.e. labor and parts) by maintenance type (ie. preventive, emergency, follow-up). Usually measured monthly, quarterly, and/or annually.
How can you use it?: Higher costs are usually the result of broken processes. This view allows you to find out which processes need work so you can increase efficiency.
For example, are work orders unclear and leading to increased repair times and labor costs? Try clarifying instructions.
Are you bringing outside contractors in to do emergency repairs? You could invest in more training for your team or hire a specialist.
#5 – Clean start-ups after maintenance
What is it?: The number of times a production line starts without stoppages or waste after completed maintenance. This is measured monthly, quarterly, and annually.
How can you use it?: Include this metric in your maintenance analysis to draw a direct line between your team’s work and increased output.
If clean start-ups are low, it gives you another chance to spot problems in your processes. For example, you might find that the specs for a production line may be out of date. This will lead technicians to rebuild components incorrectly and the line to stall. Updating the specs is a simple tweak that could lead to higher output.
#6 – Size of backlog
What is it?: The total number of hours of overdue and scheduled maintenance tasks. Track this metric weekly and monthly.
How can you use it?: This metric can be a godsend when it comes to getting your team some much-needed relief. Quantify the gap between available labor hours and your total backlog hours. You might find that the amount of backlog far outpaces how much your team can do. Use that to make a case for more budget to spend on extra overtime, hiring another technician, or bringing in more contractors.
#7 – Top 10 assets by downtime
What is it?: This is your heavy hitters list—the equipment that breaks down most often or takes the longest to repair. Keep tabs on these assets weekly, monthly, and quarterly.
How can you use it?: This metric keeps your biggest problems visible. You might raise an eyebrow at that, but highly visible problems get solved the fastest. This kind of maintenance analysis can help you prioritize your problem-solving efforts, make decisions quickly, and measure their impact.
For example, if you know asset A is at the top of your downtime list, you can start by isolating the reason why. Is it because repairs take longer on that asset? Is work being delayed? Does that piece of equipment break down again and again?
The answer to these questions will give you an idea of how to prevent failure in the future. You might get rid of obsolete parts that keep breaking. Or put an extra technician on a job. Or clarify how much lubrication should be used on a bearing. If all else fails, conducting this type of maintenance analysis helps justify a capital expenditure on new equipment.
#8 – Planned maintenance percentage (last 90 days)
What is it?: The ratio of planned maintenance to all other types of maintenance over the last 90 days.
How can you use it?: This is a measure of progress. Going from reactive to planned maintenance doesn’t happen overnight. The time frame allows you to make a clear connection between action and results. You can draw a line between what happened and its impact on your end goals.
For example, if your percentage has dropped, you can look at what happened in the last 90 days to cause that drop. That could be a massive, unexpected breakdown. Or an increase in production support during the busy season. If you want to increase the percentage, try creating a better work request process to uncover problems earlier. Or shorten inspection intervals on assets with the highest instances of unexpected downtime.
#9 – Wrench time (last 90 days)
What is it?: The amount of time technicians spend working on a piece of equipment as part of the total time it takes to complete a job. This is usually measured by job or as a weekly, monthly, and quarterly average.
How can you use it?: Wrench time is a common tool for maintenance analysis, but it’s often used the wrong way. Technicians usually (and unfairly) get the blame for low wrench time. It leads to wrench time inflation as technicians fudge the numbers to avoid trouble.
Low wrench time usually has its roots in broken processes, not the ability of the technician. That leads to bigger backlogs, more reactive maintenance, and avoidable labor costs.
To use wrench time in your maintenance analysis, start with the jobs that have the lowest scores. Review these jobs step-by-step with technicians. Work together to find out where unclear or incomplete processes cause delays. You’ll spot bottlenecks easier when breaking the task down into smaller pieces. The result is more value for your team’s time and money.
#10 – Health and safety work orders completed
What is it?: The number of work orders completed for health and safety or compliance purposes. This is usually tracked monthly, quarterly, and annually.
How can you use it?: Some metrics are quantitative. Others are qualitative. This one is the latter. And it’s essential for measuring the performance of your maintenance team and the impact it has on your business. A safe workplace keeps accidents low, and productivity and morale high. Passing audits and remaining compliant is crucial to staff safety and avoiding fines.
Three big goals you can accomplish by combining these metrics
All the metrics mentioned above are powerful in their own right. But when combined, they supercharge your maintenance analysis and help you achieve three common goals:
Get a bigger budget and more time for maintenance
Metrics to combine:
- Cost by maintenance type
- Clean start-ups after maintenance
- Top 10 assets by downtime
Getting more money and time for maintenance means winning over whoever divvies up the budget, and whoever leads production. The quickest way to get them on board is to align your plan with their goals. The three metrics above will help you get there.
First, highlight the cost-benefit of preventive maintenance. Regular preventive maintenance might seem expensive. But just one instance of emergency maintenance can cost up to $250,000. If you’re tracking cost by maintenance type, you can highlight how much the company is losing with reactive maintenance, and how much it can save you by investing in preventive maintenance.
Next, it’s time to sway the production team. Use clean start-ups after maintenance to show production that you have their best interests in mind. It emphasizes what is good for maintenance is often good for production.
No one is going to give you more resources without a plan. Your list of bad actors is a blueprint for how you’re going to make the most of your extra time and money. It quantifies the problem and makes it very clear where you’ll focus your efforts.
Get your maintenance team to buy into change
Metrics to combine:
- Planned maintenance percentage (90 days)
- Wrench time (last 90 days)
- Follow-up work created after inspections
Change sucks. And that makes it hard for your team to get on board with a new system or process. The best way to change the mind of naysayers is to show them how your plan is eliminating their biggest pains. Tracking the metrics above is one way to do this.
These data points give you a chance to compare how you operated before a change (i.e. lots of reactive maintenance and frustration over guesswork) and what you’ve accomplished since implementing a new system or process. Seeing the pay-off first-hand makes it easier to convert any critics and expand your project, whether it’s setting up a CMMS or allowing machine operators to do routine maintenance.
Build a preventive maintenance program that would make most other companies jealous
Metrics to combine:
- Cost by maintenance type
- Follow-up work created after inspections
- Cost of follow-up maintenance vs expected cost of total failure
The best preventive maintenance programs don’t have the most PMs. Instead, they have the most efficient PMs. That means doing the right work at the right time. These metrics will help you achieve this balance.
Measuring cost by maintenance type helps you allocate resources to preventive tasks and gauge the efficiency of your PMs. You can track if cost-cutting strategies are working and make sure they’re not leading to reactive costs down the line.
Keeping tabs on follow-up work is one way to optimize PM frequencies. If an inspection isn’t leading to corrective work, you can increase inspection intervals. That means you can use fewer labor hours and parts, and spend that money and time elsewhere. Similarly, comparing the costs of corrective maintenance and total failure ensures you’re not spending money on proactive tasks that aren’t worth it.
The best maintenance analysis is constantly evolving
The best maintenance metrics have a purpose. They are collected and used consistently. They guide decisions and inform you on how to run your maintenance program on a daily basis. This is the backbone of successful maintenance analysis.
On the flip side, all maintenance analysis is a work in progress. Revisit your metrics on a regular basis to make sure they’re still relevant to your goals and the way your maintenance team works. Some of the metrics listed above might work for you now, but you might find others are more effective in six months. Or maybe five years.
Lastly, the best maintenance analysis incorporates data that other departments find useful. If you can connect the metrics above to solve the challenges of other business units, you’ll be well on your way to creating a world-class maintenance program.