ABSTRACT
This chapter discusses four concepts for eliminating defects are inspection, jidoka, source inspection, and pokayoke. These concepts are part of the total-quality toolkit and are applied in concert with statistical process control (SPC) and design for manufacture, Customer-Focused Quality. Since SPC relies on sampling, it can miss occasional problems from sources that are ephemeral. The main cost for the pokayokes was the time and effort to isolate the problems and determine appropriate mistake-proofing devices. The typical contention about using self- and successive-checks is increased cycle time. Self-check inspection and correction is the most rapid kind of informative inspection system. Minimal requirements for effective screening with self- and successive-checks include setting check targets, enabling quick feedback and action, and management showing consideration of and providing support to workers. Screening with self- and successive-checks can improve quality levels beyond sampling inspection by increasing the comprehensiveness of screening and the speed of feedback.
