Total quality management (TQM) in a reverse supply chain

Six-Sigma is a newer version of Total Quality Management (TQM), and its fundamental principle is to reduce defects in processes. The traditional approach to calculate the value of n for an n-sigma process can be confusing to prospective six-sigma practitioners, because the three values of interest (viz., process capability ratio, process capability index, and n) are always different. In this paper, we present a new formula that is less confusing, and yet serves the purpose of checking how good a given process is. We apply this formula for a crucial issue (selection of potential recovery facilities) identified in the literature for reverse supply chain design. The CPC chart in the literature for selection of potential suppliers uses the process capability index alone. Since the process capability ratio too is required for judging the quality of a facility, we use the new formula for building a chart for selection of potential recovery facilities.