How to Use Root Cause Analysis Tools in Maintenance

Key takeaways

• Match root cause analysis (RCA) tools to the problem’s severity, like the 5 Whys for simple, recurring issues, and a failure mode and effects analysis for complex, high-risk equipment.
• Integrate root cause analysis findings into your computerized maintenance management system by updating preventive maintenance procedures and asset data to prevent future failures.
• Focus root cause analysis efforts on failures that are persistent or have a high impact on safety and production to maximize your team's time and resources.
• A successful root cause analysis process requires accurate data collection, including asset history, operating conditions, and maintenance logs, before analysis begins.

Get 4 practical strategies to reduce maintenance costs

Download Now

‍

Root cause analysis (RCA) gives you a structured methodology to identify and remove the underlying problem rather than just the symptoms. It's a systematic problem-solving approach that helps you understand and resolve the deeper causes of frequent unplanned downtimes for your most critical assets. 

This article has everything you need to know about the benefits of root cause analysis and the most effective RCA tools for industrial maintenance.

What are root cause analysis tools?

Root cause analysis tools are systematic approaches and techniques that identify the underlying causes of equipment failures and operational problems. According to the American Society for Quality (ASQ), root cause analysis involves a range of tools, approaches, and techniques used to uncover the primary causes of problems.

The goal of RCA is to prevent recurring issues by removing their root causes. The process follows a chain of causes and effects to pinpoint the origin.

Toyota founder Sakichi Toyoda originally developed root cause analysis to improve the efficiency of the automaking manufacturing process. Today, RCA is a critical component of the international Total Quality Management (TQM) movement, the corporate process improvement movement, and the drive for quality control.

Benefits of root cause analysis tools

The primary benefit of conducting root cause analyses is the elimination of recurrent problems. RCA enables organizations to move from short-term fixes to long-term solutions for inconvenient asset breakdowns by addressing the source of an equipment breakdown rather than just its symptoms.

Beyond this fundamental advantage, RCA delivers several additional benefits:

• Reduced maintenance costs: Constantly fixing the same equipment problem is expensive. Finding lasting solutions reduces emergency repair costs over time.
• Maintenance task prioritization: RCA helps prioritize maintenance activities for a facility's most crucial assets. Management can better determine which maintenance tasks have a lasting impact on uptime. This allows more time for high-value tasks.
• Improved safety and reliability: RCA enables organizations to provide safe working environments by eliminating issues that hamper employee safety. Employers are obligated under OSHA regulations to handle risk management. In addition, RCA helps ensure consumer products are safe, high-quality, and non-defective.
• Improved product availability: Constant equipment breakdowns affect production timelines. Delayed timelines negatively impact customer relations and reduce revenue and cash flow. Root cause analysis tools make it easier to address equipment breakdowns effectively and improve product availability.
• Improved team communication: Teams that use root cause analysis tools can better articulate exactly how and why common problems happen when writing standard operating procedures.

When teams execute RCA well, it improves both maintenance operations and a company's bottom line.

Manufacturing teams using structured RCA approaches often see improved operational efficiency and reduced maintenance costs over time. For example, some facilities achieve 30% reductions in unplanned maintenance through systematic root cause identification and corrective action implementation.

Popular methods of root cause analysis

Root cause analysis doesn't take a single approach to problem-solving. Think of it as a conceptual framework that allows you to investigate the origins of failures. This means there are many ways to execute RCA successfully.

In this section, we'll examine some of the most popular methods of conducting root cause analysis. Each benefits different industries and situations.

Failure mode and effects analysis

Failure modes and effects analysis (FMEA) is a systematic method that identifies, analyzes, and documents potential failure modes and their impact on business processes and productivity.

This framework prioritizes maintenance actions by assigning them to risk priority numbers (RPN), which quantify the severity, occurrence, and detection likelihood of potential failures. The goal is to spot potential failures before they happen and prevent their impact.

The three primary types of FMEA are:

• Process FMEA: Process FMEA helps to identify potential failures in business processes. The goal of a process FMEA is to improve the production process to prevent problems in the end product.
• Design FMEA: Organizations deploy this type of FMEA during the product development cycle. It focuses on product design and investigates safety concerns, regulatory requirements, and potential failures. A design FMEA ensures that companies deliver high-quality, safe, and reliable products to customers.
• System FMEA: A system FMEA analyzes entire systems and subsystems to ensure teams remedy potential failures that could impact overall productivity. It investigates workplace and system integration, among others.

Manufacturing, warehousing, and aerospace companies rely heavily on FMEA for safety-critical equipment. Key advantages include:

• Optimized production costs: Reduces unexpected repair expenses through proactive planning
• Minimized product recalls: Identifies potential failures before they reach customers
• Structured maintenance prioritization: Uses risk priority numbers to focus efforts on critical issues
• Evaluation controls: Provides both qualitative and quantitative assessment frameworks

Despite these benefits, FMEA does have its limitations. For example, it outlines the kinds of failures that can happen, but doesn't detail why those failures happen. Regulations also don't require FMEA teams to provide evidence of these causal relationships.

Nevertheless, FMEA remains an extremely popular root cause analysis tool within industrial maintenance settings.

The 5 Whys

Sakichi Toyoda, the Toyota founder, developed the Five Whys process to solve complex manufacturing problems. The question-based technique establishes cause-and-effect relationships by asking the question, "Why?"

The technique works on the principle that you can get to the root cause of the problem by asking, "Why" until you reach a countermeasure. The method taps into the knowledge of workers who actually run the equipment daily.

This method is straightforward yet practical. Here's how a maintenance manager at a manufacturing facility might apply the 5 Whys to a conveyor belt failure:

Problem statement: A conveyor belt broke down during peak production hours

1. Why did the conveyor belt break down? The operator overloaded it and the fuse blew
2. Why was it overloaded? The bearings were not properly lubricated
3. Why didn't the team lubricate the bearings? The lubrication pump wasn't fully functional
4. Why wasn't the pump functional? The pump's shaft wore out
5. Why did the shaft wear out? There's no way to prevent metal scraps from getting into the pump

Despite its popularity, organizations rarely use the Five Whys technique in formal investigations. Some managers criticize the method for promoting linear thinking that ignores non-obvious causes.

Critics also say the method doesn't give enough guidance for implementing solutions. The Five Whys is best for resolving minor problems and generating causes with other RCA methodologies.

Fault tree analysis

A fault tree analysis (FTA) is a graphic technique that describes a combination of possible occurrences within a system that can result in undesirable outcomes.

Initially developed by Bell Laboratories for the U.S. Air Force Intercontinental Ballistic Missile launch control system evaluation, the technique uses boolean logic. It also takes into account both human and system failures.

The process maps logical relationships between asset failures and subsystems. It places the failure that teams analyze at the top of the chart and then examines the possible causes. Teams group causes with logical "OR" combination-causing effects using a logical "OR" operator.

An "OR" points to the possibility that the cause could be one thing or another. Alternatively, an "AND" indicator suggests both factors are necessary for an issue to occur.

Additional root cause analysis methods

• 8D problem-solving: Ford Motors developed 8D problem-solving to identify, correct, and eliminate recurring problems in products and processes. Quality engineers in many industries—automotive, retail, manufacturing, and healthcare—use the eight disciplines approach to address safety and regulatory issues.
• Six Sigma methodology: The Six Sigma approach advocates using the Define, Measure, Analyze, Improve, Control (DMAIC) process to address problems systematically. Motorola developed the process to help its managers work faster while making minimal mistakes.
• Pareto analysis: Vilfredo Pareto, an Italian economist, says that 80% of consequences stem from 20% of causes. The 80/20 rule is known as Pareto's Principle. Use a Pareto chart to outline how a small number of factors cause most of the failures. Then, prioritize the causes that result in the highest number of negative effects.
• Cause and effect diagram: This tool is also known as the Ishikawa or fishbone diagram. It illustrates how the impact of a failure relates to underlying causes. This particular method is effective for visual brainstorming sessions.

Facilities that combine multiple RCA methods see 25% better problem resolution rates than single-method approaches. Different maintenance teams prefer different approaches to conduct RCA. Each method brings unique strengths to problem-solving scenarios.

If one approach doesn't deliver the desired results, choose another for a follow-up round of analysis. In complex cases, some organizations choose to hire consultants to spearhead the process.

For these reasons, it's impossible to declare any root cause analysis tool the best one. Want to continue learning more about root cause analysis tools? Check out this webcast by ASQ fellow Jim Rooney: Root Cause Analysis for Beginners, Part 1.

When to use root cause analysis tools

Root cause analysis tools include failure mode and effect analysis, fishbone diagrams,, and fault tree analysis to name just a few methods used in maintenance.

RCA delivers real value, but it's not always worth the investment for every problem. RCA requires significant money and time to execute successfully.

Put simply, it isn't feasible to rely on root cause analysis tools for every problem you encounter. While there are no rules for when to perform RCA, the following two instances provide a good rule of thumb for assessing RCA candidates:

1. Persistent faults

When an asset breaks down repeatedly, fixing the visible problem probably won't help in the long term. Dig deeper to uncover the hidden contributing factors.

Consider this scenario: A maintenance manager at a 200,000-square-foot food processing facility notices their primary packaging line experiences bearing failures every six weeks. Instead of ordering another replacement bearing (treating the symptom), they use RCA to discover that improper installation procedures and inadequate training are the real culprits.

2. Impact of failures

Managers should perform RCA in instances where equipment failures could be extremely harmful, such as an airplane crash or an oil rig explosion. Beyond safety hazards, incidents in which the cost of downtime significantly outweighs the cost of repair are strong candidates for analysis.

Proactively investigate failures that impact production, plant safety, or other critical systems. For a regional maintenance director overseeing five manufacturing sites, starting standardized RCA procedures helps identify common failure patterns across locations and develop enterprise-wide solutions that prevent similar issues company-wide.

How to conduct a basic root cause analysis

Step 1: Define the problem

Identify the problem you must solve. What's happening and what are the symptoms of the occurrence?

Write a problem statement, including a detailed description of the issue at hand. Include any available data to clarify the facts. The assessment should provide your problem-solving task force with a thorough explanation of the problem.

Step 2: Collect data

Next, dig into the failure to understand what happened and why. Use the SMART principle to ensure that the data you're collecting is specific, measurable, action-oriented, realistic, and time-specific.

Gather data about the problem itself, how long it's been happening, and what impact it's had. Teams with centralized asset data complete RCA investigations 40% faster than those using paper-based systems.

Maintenance data worth collecting includes:

• Asset age
• Manufacturer's manuals
• Machine operating characteristics
• Operating environment characteristics
• Length of time in continuous operation
• Operating patterns and maintenance history
• Machine operators and maintenance technicians responsible

We recommend using a digital platform such as MaintainX CMMS to collect asset data.

Step 3: Identify all potential factors

As soon as you've collected enough information about the problem, organize your data. Develop a structured way to analyze your data to identify any knowledge gaps.

At this stage, you're looking to determine:

• The sequence of events that preceded asset failure
• Surrounding conditions that contributed to the failure
• Any other problems that occurred as a result of the main failure

Develop a causal factor chart to provide a sequential description of the events leading to the failure, in addition to surrounding conditions. The more information you have, the more detailed your causal factor chart will be.

Identify as many causal factors as possible instead of limiting yourself to just one or two.

Step 4: Identify your root cause

Now investigate why these factors exist to find the real reason your equipment failed. For RCA to work, you need to dig deep enough to find the main cause.

When investigating root causes, remember that they should be:

• Hidden: Root causes are not typically easy to find. The goal is to uncover specific underlying reasons that you would overlook at first glance
• Cost efficient: RCA should be cost-effective and lead to lasting solutions
• Controllable: Focus on root causes that management can realistically address through specific actions

RCA assumes that all failures and systems interrelate. A single action can trigger a chain of other events. By tracing these events, you'll discover where the problem started.

Step 5: Take action

Finally, start using solutions that fix the root causes and prevent the problem from happening again. Your remedies should be actionable, achievable, and measurable.

Questions worth asking include:

• What immediate actions can we take to resume normal operations?
• How can we prevent the problem from happening again?
• How will we implement the solution?
• Does the solution pose costs and/or risks?
• Who will be responsible for it?

Remember, a single problem often has multiple solutions. Keep in mind that you need to redo the root cause analysis if the problem keeps occurring.

Unfortunately, teams commonly revisit early conclusions when they face new evidence.

Types of root causes

Maintenance teams typically encounter three types of root causes:

1. Human causes

Sometimes, failure comes from machine operators, maintenance technicians, and other individuals making a mistake. Human causes often result in physical causes. For example, car brakes can fail because the mechanic forgot to refill the brake fluid.

2. Physical causes

These are causes that result from a material item failing. For example, the windshield wipers in your vehicle lose traction over time.

3. Organizational causes

These are business processes, systems, or policies that result in faulty decision-making. For example, the vehicle's maintenance checklist didn't include a brake fluid refill, so the mechanic assumed it was unnecessary.

The final word: Transform problem-solving with data-driven root cause analysis

Root cause analysis tools provide the systematic approach maintenance teams need to move from reactive firefighting to proactive problem-solving. The key is building a foundation of accurate asset data and maintenance history that supports effective analysis.

The best maintenance teams combine solid RCA methods with digital tools that track equipment data. When you organize and make your maintenance information accessible, RCA can transform how you solve problems.

Ready to build the data foundation that makes RCA truly effective? Sign up for free to start centralizing your maintenance information and turn equipment problems into opportunities for continuous improvement.