Which process capability measurement is specifically concerned with the potential capability when in a state of control?

The process capability measurement that specifically addresses potential capability when a process is in a state of control is the Cp measurement. Cp stands for Process Capability and is a statistical measure that evaluates the capability of a process to produce output within specified limits when the process is stable and under control.

It compares the width of the process distribution (the variation) to the width of the specification limits, indicating how well the process can perform under ideal circumstances. A higher Cp value suggests that the process has the potential to produce more consistent and predictable output within the established specifications.

In contrast, other measurements such as CpK, Pp, and Ppk take into account different aspects of process performance. For example, CpK assesses capability while considering the process mean, thereby providing insight into how centered the process is within the specification limits. Pp and Ppk are related to performance and account for both population variation and process centering over time, making them less focused than Cp on potential capability in a controlled state.

Therefore, Cp is the key measurement specifically linked to the intrinsic potential capability of a process under the ideal state of control.