Glossary
DiGi Smart Control
PPM
Parts Per Million
The defect level expressed per million pieces. A common language with the customer at very low reject levels.
Formula
PPM = (Defective pieces ÷ Pieces inspected) × 1,000,000
0.1% of rejects is 1,000 PPM. With small samples PPM can mislead, so it is worth reading it together with the number of pieces inspected.
What it looks like in the system
Calculated from inspection results, also broken down by operator, machine and defect.
Related terms