February 7, 2023 | Quality
It’s not uncommon for manufacturers to run into issues with quality or other types of non-conformances. What they do next determines how effectively they can overcome that challenge and enhance their profitably when making their products.
With the workload of running day-to-day operations and the pressure of hitting sales targets, it’s easy for companies to be reactionary rather than proactive when it comes to following up on problems within their production processes. When this happens, they often only address the symptoms that crop up and attempt to do so in the least amount of time and with the least amount of effort; they take shortcuts. Unfortunately though, this often leads to the implemented measures being either wrong, or only a temporary fix.
Rather than addressing the real root cause of the problem, they treat the symptoms. As a result, they fall into a detrimental, cyclical pattern where the problem recurs. How can manufacturers escape this self-perpetuating spiral? It starts with a problem-solving method known as Root Cause Analysis and Corrective Action (RCCA).
What is Root Cause Analysis and Corrective Action?
In manufacturing, root cause analysis is a structured approach to solving problems that can arise either in the actual production process or in an administrative support process. But, what is a root cause?
ASQ defines a root cause as “a factor that causes a nonconformance and should be permanently eliminated through process improvement. The root cause is the core issue — the highest-level cause — that sets in motion the entire cause-and-effect reaction that ultimately leads to the problem.” A good visual might be a few unsightly and unwelcome weeds popping up in a bed of newly-planted grass on your front lawn. Even though you have tried many times to cut off the weeds, they just keep coming back.
So, this type of analysis empowers leaders to systematically identify the underlying causes of problems that commonly occur — whether they are related to quality, delivery, safety, efficiency, or another aspect of the manufacturing process. For example, if a product has a defect, RCCA can help you determine the “how, what, when, where, and why” the situation occurred. It helps us understand each mode of failure, and what precipitated the failure.
This due diligence and focused-analysis involves collecting and analyzing data, conducting interviews with the involved employees, and other techniques such as process mapping to understand the sequence and interaction of tasks to highlight the weak spots in the process. Ideally, after identifying the root cause, the team will apply the corrective measures necessary to resolve and prevent a recurrence. And in industries where safety is a concern, the Corrective Action Process takes center-stage in importance.
Corrective actions often result in:
- Making changes to an existing process
- Training and educating employees on the proper deployment of a process
- Implementing a new process, procedure, or policy
- Updating or revising existing safety measures
Why Does the RCCA Methodology Matter?
The point of RCCA is to be proactive by addressing causal factors — the “event or condition in the accident sequence necessary and sufficient to produce or contribute to the unwanted result” — at their source so that they don’t trouble you any further. RCCA removes emotion and bias from the equation by identifying the most important cause-and-effect relationship in the system that broke down. When conducted properly and objectively, the RCCA process can improve quality, safety, and efficiency without playing the “blame game.” It simply improves the system.
A proper application of RCCA can save your business time, money, and resources while simultaneously improving customer satisfaction.
How Do You Perform RCCA?
So, what does this process entail? We break it down into 10 steps.
1. Organize a Cross-Functional Team
Your first task is to establish and organize a cross-functional team, including representatives from various departments and functions within the organization, such as:
- Engineering
- Manufacturing
- Purchasing
- Quality
- Health and Safety
This ensures that your team can apply diverse perspectives and skills and the breadth of expertise necessary to identify root causes more precisely. A cross-section of skills and knowledge empowers the meeting facilitator to analyze the issue from multiple angles and perspectives. So, as you assemble the optimal team, remember that communication and collaboration are key. Everyone must commit to working together to focus on the problem and not take criticisms directed at the process too personally.
2. Define the Problem
A key in setting up the corrective action is properly defining the problem. The problem statement must be specific and narrowly defined to describe one and only one problem. If the problem statement is defined too broadly, it will be difficult to focus on the root cause. In fact, there might be several root causes with which to contend.
Your team’s initial challenge will be distinguishing the problem’s causes from the problem’s symptoms. Here, symptoms are signs of pre-existing issues, whereas the root cause is the core issue that might generate several symptoms.
We can separate these symptoms into two categories:1. Above the surface (easy to see and identify):
- Obvious material defects
- Broken parts
- Paperwork “triggers” – missing information to kick off the next process step
- Cost to replace parts
- Cost to process return merchandise authorizations (RMAs)
2. Below the surface (more difficult to conceptualize and identify):
- Employee overtime
- Additional freight cost to make up delays
- Administrative processing time
- Capacity constraints that diminish our ability to take on more business
- Building and maintaining extra inventory
- Extra inspection
- Unnecessary product or informational rework
- Unnecessary testing time
- Time spent placating unhappy customers
From there, you should ask follow-up questions, such as what, where, when, who, and how:
- What?:
- What equipment?
- What is wrong?
- What “should be” vs. “what is”?
- Where?:
- Which department?
- What location?
- On what part of the item did the defect occur?
- When?:
- Day, time, date?
- Which shift?
- Which part of a process?
- Is it cyclical?
- Who?:
- Which internal personnel were affected?
- Which customers were affected?
- Which business partners (external providers) were affected?
- How?:
- What events led up to the discovery?
- What and who was affected?
- Describe the triggering event.
3. Confirm the Problem with a Gemba Walk
A Gemba walk is a management technique in Lean manufacturing first created by the Japanese automobile manufacturers which involves walking the production floor. Here, the manager will observe the actual work, interview employees, and gather data about processes. The goal is to identify weaknesses and gaps to requirements, determine whether a different result occurred, and see if the problem can be duplicated. Once the issue has been understood, then the gaps can be closed and all requirements can be met. Those requirements can be internally or externally imposed.
If the issue doesn’t arise, the question becomes, “why?” — what would have to change for it to happen again?
4. Identify and Analyze Causal Factors
With the problem defined, the next step is to understand why or how the problem occurred in the first place. Without the relevant data to understand a problem’s cause, preventing recurrence comes down to luck.
Gathering root cause data requires combining a few different approaches. To start, consult any machine activity logs recorded automatically. You may also need to compile workers’ accounts, camera footage, and data from prior processes or related to inputs.
Analyzing this data should help uncover the causal factors behind the incident, such as whether the team was understaffed at the time or if a new materials supplier’s quality standards contributed. To begin your analysis, start by:
- Evaluating the equipment:
- Check if it’s in good condition and safe working order
- Perform an isolated test run of the process (if possible)
- Reviewing the process’s procedures and asking:
- Was the method approved?
- Did the method deviate from standard operating procedures? If so, how?
- Does the method have sufficient detail to enable a proper RCCA?
- Considering the materials and asking:
- Has there been a recent change in suppliers?
- Was it the appropriate quality or grade?
- Was it handled and stored properly?
- Were there any traces of contamination?
- Reviewing personnel and asking:
- Were the staff members working at the time of the problem responsible for noticing or preventing the problem? Could they have noticed or prevented it?
- Has the scheduled team been associated with similar problems?
If there are issues, you need to gather a statistically significant number of datapoints to verify that this is a real pattern and not an anomaly.
5. Formulate a Theory
Having performed a comprehensive review, you should have enough data and evidence now to formulate a theory that states the potential cause(s) or nonconformity.
The data should tell you the story. What does it say?
For instance, if the problem is environmental, you’ll want to follow up by reviewing factors like space, workflow, lighting, and ventilation. Or, if the issue has to do with personnel, you’ll want to review factors like training, qualifications, planning, scheduling, time, resources, communication, and employee physical and mental well-being/job pressures/stress.
6. Perform Short-Term Containment
Addressing a root cause issue with corrective action rarely involves immediate fixes — machine replacement or repair, new personnel or worker retraining, new suppliers, rethinking an existing process, and other solutions often create production downtime manufacturers can’t afford. So, until the corrective action takes effect, you’ll need to first focus on mitigation strategies.
To begin, establish a “containment” strategy to prevent the issue from spreading or having further negative impact. This may involve physically isolating a particular area, process, or machine. If there are no threats to worker or equipment safety identified, it may involve performing the process as normal with continual inspections throughout and additional quality assurance steps afterward.
Remember that your short-term containment efforts are only temporary measures to alleviate the symptoms in front of us. Those interim responses may impact efficiency, delivery times, or production costs, which could affect your operation’s profitability. However, depending on your corrective action timeline, you may need to maintain those short-term measures until you are able to confirm true problem resolution. It can get expensive rather quickly.
A problem’s root cause still requires corrective action, as containment will not help prevent causal factor recurrence any more than a bandage alone will heal broken bones. True solutions require following through with the full RCCA.
7. Identify and Implement Solutions For Long-Term Corrective Action
After containing the problem, start brainstorming long-term solutions. In the beginning, you may be able to formulate several possible solutions. But, through discussion, you should be able to narrow down that list to the best solution.
To create this short list, take the following steps:
- Rank the solutions: Assign weights to each one and then prioritize them from most to least effective. Choose the solution that is the combination of factors that:
- Is most likely to permanently eliminate the root cause
- Is most cost effective
- Is most appropriate to the magnitude of the problem (don’t use a large sledge hammer to drive in a small tack)
- Best implements long-term changes to the process
- Divide the solutions into sequential tasks: Some of these fixes may be multi-step. If they are, arrange them in the proper, most effective order.
- Create action items with responsibilities and assigned due dates: Once the solutions are determined, everyone involved should be assigned tasks and expected completion dates to ensure a change is implemented. Project management becomes most important.
- Establish a contingency plan: If everything doesn’t go according to plan, what then? You should take the time to ask and answer the following questions:
- What could go wrong?
- How will we know it?
- How can we prevent it or at least mitigate it?
8. Monitor and Verify the Solution
Next, you’ll monitor the situation to ensure that your implemented fixes achieved their intended impact and prevented the issue from recurring. If your corrective action was successful, this may merely involve confirming any new issues are absent from the gathered data, inspection reports, and your observations. But what happens if the problem does recur?
You’ll need to reject the initial root cause determination and try a different solution. Revisit your investigatory data to identify a different root cause. Be sure to expand your investigatory scope as well to identify whether the issue occurred elsewhere during production processes.
To protect client relationships, you should also determine if any products with defects were shipped to customers and what actions you must now take. This likely involves replacing the product at no charge. You should check products that have recently shipped, products that are still in transit, and products that might be in the customer’s warehouse or stockroom.
Depending on the business relationship, such as manufacturing components for another business to assemble, you should proactively provide information about your problem and the temporary containment and long-term corrective actions that you’ve begun implementing. And if you are in a regulated industry supply chain such as medical, aerospace, or automotive, you might be required to disclose the problem and even perform a product recall.
9. Verification
Monitoring your corrective action’s success requires more than a few days. It may take weeks or months of careful observation to ensure that the problem has been fully resolved. So, be patient and allow as much time as needed before assuming that issue has been eradicated. This step is often missed, and that’s why we see the same problems repeat themselves.
10. Update the Documentation and Procedures
Once you’ve verified that your corrective actions have had the desired effect, you should update your existing documents and procedures so that they can be used as instructional materials to train others so that the issue doesn’t crop up again.
Revise your current documents accordingly, including:
- Procedures, work instructions, and standard work
- User handbooks with photos to add details and guidance
- Guideline specifications
- Service manuals
Distribute the new procedures to the affected employees in the relevant departments, provide appropriate training, and confirm that they understand and will follow these new methods. If your company maintains any of the quality certifications such as ISO 9001, there is an additional requirement to verify that the employee is fully competent in the revised process.
WMEP Manufacturing Solutions Helps Small and Medium-Size Manufacturers Improve their Quality and Safety Processes
RCCA supports operations improvements by promoting the problem-solving culture of team communication, resulting in behavior change and company culture focused on quality. Rather than simply dealing with symptoms in a reactionary manner, you can train your team to address the root causes. This way of thinking encourages deeper employee engagement and real empowerment throughout your workforce. We want the employees to drive the problem-solving process.
And WMEP is here to help you teach the RCCA process every step of the way.
Our team is composed of high-quality consultants from diverse backgrounds, bringing unique skill sets and expertise. We provide advice and guidance that Wisconsin manufacturers need to overcome any hurdle that arises.
Want to learn more about our services? Contact us today!
About the Author of this original article.
Eliot Dratch is a quality, lean and safety consultant who understands that U.S. manufacturing has been the economic engine that raised the living standards and built economic equity for the last 6 generations of Americans. Eliot’s work with manufacturers for his entire 30+ year career from different manufacturing sectors allows him to leverage a unique blend of experience for his clients. His goal is always to measurably improve a CMTC client’s productivity, safety and profitability.