Process capability which is a measurement with respect to the inherent precision of a manufacturing process has two significant elements, i.e. process factor and process conditions. Process factor includes raw material, machine or equipment, operator's skill, measuring devices, etc. To conduct the process capability study process must be examined under normal conditions keeping the input fixed or standardized.
PC studies of the process capability can answer the process ability to meet the specification and whether the process is well centered w.r.t. the desired nominal specification. Process capability is defined as the ratio of specification spread and process spread, i.e. six times of standard deviation. However, the quality losses can be calculated using conventional method or the quality loss function method.