Useful Root Cause Analysis Tools to Use in Each Phase of the RCA Process
RCA is used to investigate and address unwanted problems, troubles, and failures, be they within a procedure; from a business or operational process; or in a physical asset.
Root Cause Analysis (RCA) is a problem-solving methodology that steps you through the RCA process. Each RCA process phase has a range of root cause analysis tools that you can use. The RCA process starts at the problem event then moves through evidence collection, investigation, analysis, developing corrective actions to address the problem or a failure, and concludes with the RCA Report.
Figure 1 is a slide from our online root cause analysis training course by tutored distance learning. It shows the basic RCA process and the root cause analysis tools you can use in each step. There are more advanced, highly technical RCA tools too, but the ones bullet pointed in Figure 1 are the foundational tools that can be applied in every RCA.
Evidence Collection Phase Root Cause Analysis Tools
At the beginning of an RCA, you want to understand what happened before and during the failure event. You seek information and data from all possible sources about the history leading up to the incident. There are several RCA tools to use, like:
- Protect Equipment/Location
- Documents, Records, Diagrams
- Creative Disassembly of Parts
- Scatter Diagrams
- Control Charts, Run Charts
- Expert Investigation
The Evidence Collection RCA tools aim to garner all that is known about the situational circumstances, including personal experiences, the engineering and technical details, the relevant body-of-knowledge, and what is recorded in the organization’s systems.
Investigation Phase Root Cause Analysis Tools
Once evidence is collected, it is necessary to find the truth amongst the noise. The event history is investigated with root cause analysis tools like those noted below.
- Process Mapping Flowchart
- Fishbone Diagram
- Cause and Effect Map
- Timeline Plots
- Distribution Histograms
- Pareto Charts
- Failure Mode Effects Analysis (FMEA)
These RCA tools interrogate the event data, records, and information. They force you to look for the factual details of the incident. They allow you to identify relevant and missing aspects to explain what occurred.
Analysis Phase Root Cause Analysis Tools
Now that we have the full, accurate history, we need RCA tools to help understand the sequence of cause-effect events associated with the incident. Common tools often used include:
- Brain Writing
- Is-Is Not Table
- Why Tree (Fault Tree Analysis)
- 5-Why Table (to test the Why Tree)
At this point in the root cause analysis process, it is time to confirm the truth and provide sure proof. The analysis phase tools review the sequence of operations, actions, decisions, and misunderstandings that led to the failure event.
Corrective Action Choice Phase Root Cause Analysis Tools
Finally, a viable, practical, and affordable solution needs to be found to put into the RCA Report. The following RCA tools can be used to help find an effective solution to address the factors that caused the problem.
- Evaluation Table
- Affinity Diagrams
- Relationship Digraph
The recommendation chosen for the RCA Report must stop the event from happening again at a cost the organization can pay for to implement. Proposed solutions must be sure to address as many factors related to the causes of the event as possible. These choice-making tools give you a means to confirm that what is recommended does focus on addressing the incident’s causes at an affordable price.
Once the Root Cause Analysis Report is passed to Management the RCA is finished. The decision to make recommended changes is the responsibility of Management. When the go-ahead is given the required work is an improvement project and project management methodology is applied.