Quality Improvement Through Inspection

An important aspect of Total Quality Management is to inspect work in process after each operation. One of the reasons to do this is that a quick feedback to the operator of the information gathered during inspection can greatly help in improving quality levels at that operation. This paper presents a new model of the effect of inspection on quality improvement in a production line. The inspection policy derived from this model gives a good insight on how learning influences the economic decision to inspect or not. Our results support the recommendations of the total quality theory to inspect all along the production line to improve quality, even when inspection does not seem economical on its own merits (Le. without learning effects). Nevertheless, the model shows that there is some limit to the quality improvement efforts that are economically justified.