A few years ago I wrote about the inspection levels, but I regularly notice that some people are confused about the "special" levels (S1, S2, S3, and S4). Here is what the ISO 2859-1 standard says (emphasis is mine): The inspection level designates the relative amount of inspection. Three inspection levels, I, II and III, are given in Table 1 for general use. Unless otherwise specified, level II shall be used. Level I may be used when less discrimination is needed or level III when greater … [Read more...]
Quality Assurance, Product Development, and Purchasing Strategies in China