Re: IS - IS NOT analysis
It is based on answering most of the 5W2Hs
What
What is the object with the defect?
What is the defect?
When
When was the defect first seen?
When else was the defect seen?
When in the life cycle was the defect seen?
Where
Where on the object was the defect seen?
Where geographically was the defect seen?
Who
What parties are involved?
How Much
How many units exhibit the defect?
How many defects per unit?
What rate of defects (e.g., %, PPM, etc.)?
After answering the Is question for the above questions, answer what the defect is not, but could have been.
Then identify the differences between the Is and the IS Not, any changes to the materials, process, detection method, etc. and theories as to how these could explain the defect.
This analysis is used to provide focused potential causes for further investigation, and alos provide a test for potential root causes. Root causes must account for all of the IS/Is Nots.