With national trade barriers falling, causing the expansion of the com­ petitive global market, the question of quality control has become an essential issue for the 1990s. The time where the promise was to replace a product if it does not work seems to have passed; what is more impor­ tant now is not so much a reduction in what is going wrong but an increase of what is going right the first time (Feigenbaum 1990). This new trend is sometimes referred to as total quality. Among the many advantages ofthis zero-defect manufacturing policy, we can enumerate (Laurin 1990): superior marketability of wholly de­ pendable products, enormous gain in productivity, elimination of waste­ ful cost in replacing poor quality work and retrofitting rejected products from the field. Although total quality is a relatively new and attractive concept for mass products such as cars, consumer electronics and per­ sonal computers, in many fields, mainly aerospace and military, it has been the rule for years because of security reasons.