TOPIC: even if one data point is above or below upper/Lower control Limits,

even if one data point is above or below upper/Lower control Limits,is process considered to be out of control?

Gulraiz:

I'll let one of the PM Pros answer your specific question, but from a Quality Assurance/Quality Control (production analytical chemistry) perspective

The measurement of of a single point outside the LCL or UCL will declare data that was acquired from the latest "in-control" reading and the "out of control" reading as suspect or null, depending on the quality assurance program. From a chemistry perspective (my area of expertise), there will be two sets of quality measurements - one for the instrument and one for the batch of analyses. Instrument QC measurements are normally conducted every 24 hours so that a lot of data is not wasted in the event of an Out of Control measurement. Batch QC measurements are done and if found out of control the entire batch is discarded and repeated.

Harry

Thanks sir Harry.

So answer to my question is yes?

Gulraiz,

Before I lead you astray, I need to do some research on the question. I know what "my" answer is, but I do not know what the answer is from PMI's, and hence, the exam perspective.

Harry

Gulraiz,

I could not find a definitive answer from PMI resources after looking for a couple of hours. With that, I would say that if a single point is outside the control limits, the process is out of control.

Harry