This tutorial explains how to calculate the process sigma value.
Opportunities = Lowest defect noticeable by customer DPMO = Defects Per Million Opportunities
In hardware company hard disk manufactured is 10000 and the defects is 5. Find the process sigma.
Opportunities = 10000
Defects = 5
Process sigma
Substitute the given values in the formula,
DPMO = (Total defect / Total Opportunities) x 1000000
= (10000/5) x 1000000
Defect (%) = (Total defect / Total Opportunities) x 100%
= (10000/5) x 100
Yield (%) = 100 - Defect (%)
= 100 - 0.05
Process sigma = 0.8406 + √(29.37)-2.221*(log(DPMO))
= 0.8406+sqrt(29.37)-2.221*(log(500))
= 4.79
Process sigma = 4.79