Maybe you already read somewhere that 80% of maintenance errors involve human factors. That number is thrown around a lot, and it comes from a 2008 handbook for aviation maintenance technicians. If that rate of human errors remains the same today, and if that percentage is similar across industries, we can’t say. However, there’s one thing we’re sure about: Everybody makes mistakes. 


As a manager, you can’t defeat human nature. But it’s possible to nurture situations and conditions that don’t lead to error as often. Today we want to look at how you can reduce human errors in maintenance and prevent them with people skills, technology, and data! 


Are all errors honest mistakes?

There are two types of mistakes, intended and unintended. Intended mistakes are deliberate violations, something one does out of disregard for the rules, inability to follow them, or occasionally as a thrill-seeking behaviour. Generally speaking, this is something you need to address as a team.


Then there are unintended mistakes, which are more benign in nature. They may be slip-ups or momentaneous lapses, and happen to the best of us. But why do we make these mistakes? And how can we prevent them from happening? That is what we’ll focus on for the first part of the article. 


Why do we make mistakes? (And how to avoid them)


This may sound like a question you’d ask at 2 a.m., fresh out of a terrible plant breakdown. But there are several mechanisms that lead humans to make errors, and it’s interesting to explore them. Otherwise, how will you ever get better at preventing them? (And, fun fact: we’re more likely to make mistakes in the wee hours of the morning, so avoid making decisions at a, after a breakdown.)


Memory, attention and the “conscious workplace”

Attention is a limited resource. We pay attention for a limited period of time, and we’re selective. Each of us processes only a limited amount of information and sensory data. That’s why an unrelated distraction may be enough to derail us on a standard procedure or to forget what we meant to do next. There may also be momentaneous slips, like forgetting something we know or failing to notice a problem. 


  • Develop standard operating procedures 

Developing standard operating procedures is the best way to counter memory failures and small slips. Although work orders compile a lot of information, standard operating procedures that are user-focused improve compliance and quality. You want to keep these statistics in mind:


Written procedures reduce error to 5% 

Written procedures with a checklist reduce it to 1% 


  • Automate processes

Another way to avoid human error… use machines instead. Automate as many processes as you can on your maintenance platform! For example, if people keep going off track or forgetting things, register everything on the platform and let push notifications do their jobs.


  • Control distractions 

If your employees often get distracted, you can help them in a number of ways. First of all, when everyone is aware of this risk, they’ll think twice before interrupting. But you can also improve room layout, provide visual cues, allow them to mute notifications before they finish their current job, and so on. 


Reduced vigilance and skill-based slips 

How many times have you looked for something that was right under your nose? The more time inspectors take to perform an inspection, the more likely they are to miss obvious faults. Apart from these mistakes, there are also skilled-based slips. This means we turn to an “automatic” mode and resort to unintended routine behaviour, even when we’re not supposed to (for example, using a common tool instead of the one the work order calls for).


  • Distribute workload and manage fatigue

The number of hours someone has been working for, and even the time of day (which affects technicians working different shifts) can impact someone’s ability to perform a task correctly. Keep this in mind when you’re distributing tasks and don’t leave the most demanding tasks for the worst times.


  • Assign tasks appropriately 

The most and least performed tasks are more likely to result in errors. Take this into account when assigning tasks and seek some ‘variety’ for each technician to avoid skill-based slips. Besides, you’ll guarantee technicians don’t go out of practice! 


  • Address burnout

A 2018 study found that 23% of field technicians feel burned out at work “very often or always” and 44% feel burned out “sometimes”, which means 67% (two thirds!) aren’t at the height of their capabilities at work. Check in regularly with each worker to make sure they’re feeling well and cared for.


Lack of knowledge or skill 

Sometimes, it just comes down to the ineptitude of the person carrying out the repair. Everyone bites a little more than they can chew from time to time because it’s not easy to admit ‘I don’t know’. Before you assign a task to a technician, make sure they have the right training and experience with similar equipment.


  • Provide training 

Make sure no one takes on a task for the first time without proper training. But that’s not all. You should make everyone aware of situations and factors that may lead to error, like fatigue or pressure, to help technicians watch out for themselves and suggest ways to avoid errors.


  • Encourage mental rehearsal 

Before performing a task, encourage technicians to do a mental rehearsal. Going over every step beforehand improves their mental readiness – which, in turn, improves quality and reliability. In the future, this “rehearsal” may be even more accurate with the help of augmented reality, for example.



No one is immune to biases, including managers. We often suffer from confirmation bias – meaning that we tend to look for data that confirms our initial suspicion. Apart from this bias, there’s emotional decision making. When we’re frustrated, for example, we might make decisions in the heat of the moment without weighting all the options carefully.


  • Audit regularly

Instead of letting biases cloud your judgment, look at the data. Apart from the data reports, you can set tasks, run automatic audits and make an informed assessment. Need more info? Here’s another reminder why you should do maintenance audits and how to do an audit.


System errors 

A few years ago, a study in fossil power plants made a curious discovery.  56% of breakdowns happened less than a week after a planned maintenance shutdown. Why? Probably because the system wasn’t properly inspected or tested before operating again. 55-65% of these breakdowns were related to human performance.


  • Put safety checks in place

Use procedures like lockout-tagout to make sure equipment doesn’t pose a danger to anyone. Besides, it’s helpful to have the equipment’s logs to check what went wrong in previous shutdowns, which life cycle stage it is in, and so on.


  • Promote inspections

A fresh pair of eyes is the best way to find a mistake and prevent the worst consequences. Get a second person to inspect equipment before having it back up again. Extra tip: use a checklist to help the designated inspector (no reduced vigilance here!).


Intended violations

It’s like violations don’t deserve their own chapter (or, in this case, their own article), but we’re trusting the good-will of your employees. Violations are usually classified as routine violations in order to avoid effort (like crossing the street at the wrong place); thrill-seeking violations to avoid boredom or achieve praise (like driving above the speed limit); or situational (it’s not possible to follow rules). The only way to circumvent this is by establishing an intolerant culture to error. 


  • Hold people accountable

Hold people accountable for their mistakes. We’re not suggesting implementing a “culture of fear” – that might backfire spectacularly – but you need to make them understand the consequences of their errors. The culture of ‘accountability’ should exist even between peers to build a natural intolerance to violations.


  • Target deliberate violations

Deliberate violations, especially when they’re for the sake of a thrill, are serious matters. Investigate them thoroughly, find out who did it, and get to the root cause. Sometimes it might be necessary to display a harsher stance – it’s important that violations don’t become routine.


  • Provide leadership 

Providing leadership is one of the best ways to create a healthier culture that doesn’t breed wrongdoers. Provide subordinates with directions and goals, be transparent with them, be open to change processes, explain procedures are not a “whim” and keep investing in your staff’s technical skills. 


Learn from your mistakes

Remember when we said that a root cause analysis should never end at “human error”? Errors are consequences, not causes. Investigate why recurrent errors keep happening – there’s a 100% chance something needs improving. Root cause analysis may be a great ally in your investigation. You might also want to look into FRACAS – Failures Reporting Analysis and Corrective Action System and use mistakes as an opportunity to improve. 


Maintenance is a demanding job that requires attention to detail and great skill. Perhaps that’s what makes it particularly error-prone. However, it’s futile to try and change human behaviour. Managers must treat human errors as normal, expected, and a foreseeable aspect of maintenance work. In other words: don’t change people, change the conditions people work in.