Root Cause Analysis (RCA) is a method used to find the root cause of any malfunction, deficiency, or problem. It is most famously used in industries such as healthcare, science, and manufacturing/engineering but its principles can be used in any environment.
As a fundamental problem-solving tool, Root Cause Analysis focuses on finding the source of the problem in order to enact effective and long-lasting solutions. Take for example someone complaining of a sore ankle. You could simply give the person some pain medication but that does not solve the root cause of the pain, only the symptom of pain.
With Root Cause Analysis, you’ll be able to discover and define what happened, why it happened, and how to prevent it from happening again.
Root Cause Analysis is used to determine the root cause of problems within a variety of industries and fields.
The 4 steps of Root Cause Analysis are identification, data collection, causal graphing, and solution.
Always make sure to differentiate between correlational factors and contributing factors.
Use tools like the 5 Whys or the Fishbone Diagram to map out causal factors.
Within manufacturing or any company environment, all causal factors can be broken up into 3 broad categories.
Most problems or malfunctions involve multiple causal factors. For example, there may be an issue with a machine (physical cause), which is due to a lack of maintenance, (human cause), which is due to the lack of a maintenance schedule being established (organizational cause).
Breaking this up into even smaller categories will provide even greater insight into the root causes of a problem. But these 3 broad categories are a great place to start.
Root Cause Analysis can be performed in a myriad of different ways but more often than not, the process follows these 4 core steps.
When collecting data, make sure to carefully differentiate between correlational factors and contributing factors. More often than not, there will be a lot of factors that coincide with the occurrence of a problem while not necessarily contributing to the issue.
The 5 Whys can be used in almost any Root Cause Analysis as it is a fairly simple process. The idea is to ask “why” five times when presented with a problem. This way you can progressively move from superficial causal factors to the ultimate root cause.
For example, imagine your company fabricates and assembles high-quality mechanical seals, similar to Chesterton. Quick side note, did you know they cut their training time in half by using VKS?
Back to the scenario. Lately, the seals have been failing inspection. Why? The operators are not assembling them correctly. Why? The operators are not 100% sure how the seals should be built. Why? Because they are new employees that lack sufficient training. Why? Because we don't have an adequate training program for our new employees. Why? Because the company is not prioritizing workforce improvement and training.
And here we have found the answer to our hypothetical problem. In this situation, the 5 Whys would be mapped like this.
Now the number of why’s is not a hard and fast rule. In reality, you’ll want to ask somewhere in the realm of 3-7 whys. If under that range, you’ve most likely not delved deep enough into the root cause. If over that range, you’ve most likely progressed too far into factors that are outside of your control such as the weather or global events.
This occurrence is easily avoided by using work instruction software to quickly and effectively train new hires while providing on-the-job guidance.
The fishbone diagram is used to investigate multiple factors that lead to one larger problem/failure/event. The resulting diagram displays all causal factors leading to the problem, which closely resembles the figure of a fishbone.
For instance, imagine your facility has been experiencing 7 separate and seemingly unrelated accidents in the past month. This is hurting productivity and is costing a significant amount in maintenance and downtime. You call a meeting with all your employees and go over the factors that have led to the higher rate of accidents and create a fishbone diagram. This breaks up all the accidents into a few basic categories to discern what areas within the operation need the most focus.
Here we can see that the bulk of the accidents fall under methods and manpower. Knowing this and unraveling it as a team enables you to find the right solutions and make an informed difference.
If having trouble knowing how to break up your fishbone diagram, try using the 5 Ms of manufacturing used in the above diagram. These are Manpower, Machines, Measurements, Methods, and Materials. You can add other factors like Environment or Money as long as they are useful to your Root Cause Analysis.
One thing to look out for with Root Cause Analysis is to make sure the solution does not cost more than the problem. Wanting to know if our processes and machines are working properly as this is never a bad thing. But at the end of the day, the solution should not cost more than living with the problem. The solution should always bring in a greater return on investment.
This is why Root Cause Analysis is key to a successful and well-maintained operation. It allows people to gain key insight into the causal factors within their operation to make smart decisions and find effective solutions.