What does First-pass yield measure?

What does First-pass yield measure?

• A. The proportion of units that pass inspection on the first pass without rework.
• B. The total number of defects per million units.
• C. The rate of production line stoppages.
• D. The ratio of inventory to sales.

Answer: (D)

First-pass yield measures the proportion of units that pass quality checks on the first attempt, without needing any rework. It is calculated as the number of units that exit the process after the first pass divided by the total number of units that entered the process. A high FPY shows the process is effectively producing good quality units without rework, while a low FPY signals more defects requiring rework and higher costs. This is different from defects-per-million, which counts defects rather than whether a unit passed first time; it also isn’t about production stoppages or inventory levels, which are separate performance measures.

First-pass yield measures the proportion of units that pass quality checks on the first attempt, without needing any rework. It is calculated as the number of units that exit the process after the first pass divided by the total number of units that entered the process. A high FPY shows the process is effectively producing good quality units without rework, while a low FPY signals more defects requiring rework and higher costs. This is different from defects-per-million, which counts defects rather than whether a unit passed first time; it also isn’t about production stoppages or inventory levels, which are separate performance measures.