Within our manufacturing process we leak test tubing using a negative air leak test. Basically, it is a vacuum test that detects the flow of air inside the tube when there should not be. The test is a simple pass/fail process.   If it detects a leak, it fails the tube, and if it does not detect a leak, then it passes. The attribute control chart that would be used to help stabilize the process would be a P control Chart. The P control chart looks at variation as a yes or no attribute (pass or fail) and is used to calculate the fraction or percentage of defective or failed parts within a given value (time, quantity). In this scenario, we would need to determine the value we are going to track. In this case what are the challenges of using Pcontrol chart and what other charts we could use.