Content By William A. Levinson

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By: William A. Levinson

Anthony Chirico1 describes how narrow-limit gauging (NLG, aka compressed limit plans) can reduce enormously the required sample size, and therefore the inspection cost, of a traditional attribute sampling plan. The procedure consists of moving acceptance limits t standard deviations inside the engineering specifications, which increases the acceptable quality level (AQL) and therefore reduces the sample size necessary to detect an increase in the nonconforming fraction.

William A. Levinson’s picture

By: William A. Levinson

Inspection is a mandatory but nonvalue-adding activity, and our objective is to do as little as possible, provided that we continue to fulfill the customer’s requirements. The zero acceptance number (c = 0) sampling plan requires far less inspection than the corresponding ANSI/ASQ Z1.4 (formerly MIL-STD 105) plan, and becomes viable when the supplier is extremely confident in its level of quality.1

William A. Levinson’s picture

By: William A. Levinson

The Pareto principle calls for focus on the vital few rather than the trivial many. While none of ISO 9001’s clauses are trivial—a nonconformance for any of them requires corrective action—ISO 9001 users can avoid most nonconformances by focusing on the clauses that are the most frequent trouble sources, and also on what look like frequent common root causes for most of the nonconformances.

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By: William A. Levinson

Chad Kymal1 gave an excellent overview of the ISO 45001 occupational health and safety (OHS) standard that was released in March 2018. I purchased a copy of the standard, and it provides an excellent framework, modeled on Annex SL, which defines the structure of all the new ISO standards, for an OHS management system.

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By: William A. Levinson

ISO 9004:2018—“Quality of an organization—Guidance to achieve sustained success” expands considerably on the former (2009) revision. It introduces the important concept of “quality of an organization” (Clause 4.1), which makes excellent sense. If the organization’s processes are of high quality, we can expect good outputs, or at least rapid corrective and preventive action (CAPA) in response to problems.

William A. Levinson’s picture

By: William A. Levinson

Quality and manufacturing practitioners are most familiar with the effect of variation on product quality, and this is still the focus of the quality management and Six Sigma bodies of knowledge. Other forms of variation are, however, equally important—in terms of their ability to cause what Prussian general Carl von Clausewitz called friction, a form of muda, or waste—in production control and also many service-related activities. This article shows how variation affects the latter as well as the former applications.

William A. Levinson’s picture

By: William A. Levinson

A job safety analysis (JSA) worksheet is almost identical in organization to a job breakdown sheet and standard work, all of which assess a job (or process) on a step-by-step basis. This suggests combining standard work with job safety analysis to support ISO 45001.

William A. Levinson’s picture

By: William A. Levinson

Inspection is a mandatory but nonvalue-adding activity, and our objective is to do as little as possible, provided that we continue to fulfill the customer’s requirements. The zero acceptance number (c = 0) sampling plan requires far less inspection than the corresponding ANSI/ASQ Z1.4 (formerly MIL-STD 105) plan, and becomes viable when the supplier is extremely confident in its level of quality.1

William A. Levinson’s picture

By: William A. Levinson