Defects per million opportunities


In process improvement efforts, defects per million opportunities or DPMO is a measure of process performance. It is defined as
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A defect can be defined as a nonconformance of a quality characteristic to its specification. DPMO is stated in opportunities per million units for convenience: processes that are considered highly capable are those that experience fewer than 3.4 defects per million opportunities.
Note that DPMO differs from reporting defective parts per million in that it comprehends the possibility that a unit under inspection may be found to have multiple defects of the same type or may have multiple types of defects. Identifying specific opportunities for defects is an art, but generally organizations consider the following when defining the number of opportunities per unit:
  • Knowledge of the process under study
  • Industry standards
  • When studying multiple types of defects, knowledge of the relative importance of each defect type in determining customer satisfaction
  • The time, effort, and cost to count and categorize defects in process output

Other measures

Other measures of process performance include: