Definition DPMO - Defects Per Million Opportunities

Defects per million opportunities (DPMO) - The average number of defects per unit observed during an average production run divided by the number of opportunities to make a defect on the product under study during that run normalized to one million.

Defects Per Million Opportunities is synonymous with PPM.

To convert DPU to DPMO, the calculation step is actually DPU/(opportunities/unit) * 1,000,000.

A couple Elsmar Cove discussion threads:
How to define and Calculate the DPU, DPMO, Yield, Rolled Throughput Yield ( RTY)
and
How to decide the “U” to calcuate DPU and "opportunity" of DPMO

DPMO in the Elsmar Cove Wiki.

Marc said:

Defects per million opportunities (DPMO) - The average number of defects per unit observed during an average production run divided by the number of opportunities to make a defect on the product under study during that run normalized to one million.

Defects Per Million Opportunities is synonymous with PPM.

Click to expand...

I'm not sure I would call it synonymous. I understood it as:

PPMs are typically defective units per million units produced.

DPPOs are typically defective opportunities per million units produced.

A complex part could have a 100 opportunities per unit. So, if there were 1,000,000 units, there would be 100,000,000 opportunities.

So, if there were 100 parts with a defective connector in a lot of 1 million units, it would be 100ppm, but only 1 dppmo.

Some would say this is playing games with the stats, others would argue it is a more accurate way to look at defects, because it factors in complexity.

My opinion is use whichever tool you feel is more appropriate to your situation, just use them correctly.

PS: OE customers generally just consider PPM per units, not opportunities. But, opportunities may be appropriate for internal analysis.