Root Cause Analysis is the frequently used and Popular Method to aid to catch the exact reason of a problem. It will help you to find out the primary cause of the problem, so that we can determine what happened, why it happened and also formulate the Prevention so that problem will not occur again. It’s a vital part of the Continual Improvement.
Root Cause Analysis Process:-
Root Cause Analysis has Eight Steps:
Define the Problem: – This step will
help you to understand the problem definition.
Identification of Problem: – What
exactly happening, Where the problem is being occurred and what is the symptoms
of the problem.
Collect Data – Before collecting the Data, You have to plot thePareto Chartof Existing Past data for last six month at least. Then formulate the template according to the higher contributing causes by the help ofPareto Principle (80/20 rules). Set up the Template machine wise, process-wise and shift wise etc. At least collect the data for three months.
Represent The Potential Cause: – Now you have to plot the Pareto chartwith the Present collecting data. Next, to apply the Pareto principle to identify the Problems among the set, those are coming under the 80% contribution.
All Problems these are coming under the 80% contribution need to be plot the Fishbone Diagramindividually to represent the Potential Causes.
Find out the significant Causes: –
Hypothesis test needs to be executed here to find out the significant reasons.
For example, let we have taken the
Shrinkage as the problem, which is coming under the 80% contribution (Decision
will come from Pareto chart considering with its Principle rules). Let Shrinkage has the three potential causes
as  High Pouring Temperature,  Wrong Gating System Design,  High Carbon
Equivalent. To find out the significant causes among the three problems. We
have to do the Hypothesis test as
per the below pattern as
 High Pouring Temperature vs.
 Wrong Gating System Design vs.
High Carbon equivalent vs.
After doing the hypothesis testing as per the above pattern, one or number of causes will come to the point as significant Causes.
Now you have to follow the step six
to identify the Root Cause.
Identify the Root Causes:-
Before you execute the root cause identification. All Significant causes need to be listed up. Thereafter we have to do the Why-Why Analysis of all individual significant causes until to get the Root Causes.
CAPA: Corrective and Preventive Action
Plan to be Prepared.
Effectiveness of CAPA: – After
implementation of CAPA, Trend Analysis need to be plotted to figure out the
effectiveness of CAPA or Action Plan. If the Action Plan will fully effective
then control mechanism and action plan need to the incorporated in relevant
documents (e.g. FMEA, SOP, Control Plan etc.).