quality control

{{See also|History of technology}}

Early stone tools such as anvils had no holes and were not designed as interchangeable parts. Mass production established processes for the creation of parts and system with identical dimensions and design, but these processes are not uniform and hence some customers were unsatisfied with the result. Quality control separates the act of testing products to uncover defects from the decision to allow or deny product release, which may be determined by fiscal constraints.{{cite book|last1=Shewhart|first1=Walter A. (Walter Andrew)|last2=Deming|first2=W. Edwards (William Edwards)|title=Statistical method from the viewpoint of quality control|date=1939|publisher=The Graduate School, The Department of Agriculture|location=Washington|pages=1–5|url=https://archive.org/stream/CAT10502416#page/2/mode/2up}} For contract work, particularly work awarded by government agencies, quality control issues are among the top reasons for not renewing a contract.{{cite web |url=http://www.opm.gov/fedclass/gs1910.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.opm.gov/fedclass/gs1910.pdf |archive-date=2022-10-09 |url-status=live |title=Position Classification Standard for Quality Assurance Series, GS-1910 |date=March 1983 |publisher=US Office of Personnel Management |access-date=21 December 2012 }}

The simplest form of quality control was a sketch of the desired item. If the sketch did not match the item, it was rejected, in a simple Go/no go procedure. However, manufacturers soon found it was difficult and costly to make parts be exactly like their depiction; hence around 1840 tolerance limits were introduced, wherein a design would function if its parts were measured to be within the limits. Quality was thus precisely defined using devices such as plug gauges and ring gauges. However, this did not address the problem of defective items; recycling or disposing of the waste adds to the cost of production, as does trying to reduce the defect rate. Various methods have been proposed to prioritize quality control issues and determine whether to leave them unaddressed or use quality assurance techniques to improve and stabilize production.

There is a tendency for individual consultants and organizations to name their own unique approaches to quality control—a few of these have ended up in widespread use:

In project management, quality control requires the project manager and/or the project team to inspect the accomplished work to ensure its alignment with the project scope.{{Cite web|last= Phillips |first= Joseph |title= Quality Control in Project Management |url= http://www.pmhut.com/quality-control-in-project-management |date=November 2008 |publisher=The Project Management Hut |access-date=21 December 2012 }} In practice, projects typically have a dedicated quality control team which focuses on this area.{{cite book |title=Project Quality Management: Why, What and How |author=Rose, K.H. |publisher=J. Ross Publishing |pages=224 |year=2014 |isbn=9781604271027}}

• Analytical quality control
• Corrective and preventative action (CAPA)
• Eight dimensions of quality
• First article inspection (FAI)
• Good automated manufacturing practice (GAMP)
• Good manufacturing practice
• Quality assurance
• Quality management framework
• Standard operating procedure (SOP)
• QA/QC

{{Reflist}}

• {{FS1037C MS188}}

• {{Citation | last = Radford | first = George S. | year = 1922 | title = The Control of Quality in Manufacturing | publisher = Ronald Press Co. | location = New York | oclc = 1701274 | url = https://archive.org/details/controlofquality00radf | access-date = 2013-11-16}}
• {{Citation | last = Shewhart | first = Walter A. | author-link = Walter A. Shewhart | year = 1931 | title = Economic Control of Quality of Manufactured Product | publisher = D. Van Nostrand Co., Inc. | location = New York | oclc = 1045408}}
• {{Citation | last = Juran | first = Joseph M. | author-link = Joseph M. Juran | year = 1951 | title = Quality-Control Handbook | publisher = McGraw-Hill | location = New York | oclc = 1220529}}
• {{Citation | author = Western Electric Company | year = 1956 | title = Statistical Quality Control Handbook | edition = 1 | location = Indianapolis, Indiana | publisher = Western Electric Co. | oclc = 33858387| author-link = Western Electric Company | title-link = Statistical Quality Control }}
• {{Citation | last = Feigenbaum | first = Armand V. | author-link = Armand V. Feigenbaum | year = 1961 | title = Total Quality Control | publisher = McGraw-Hill | location = New York | oclc = 567344}}

• [http://www.astm.org/Standards/quality-control-standards.html ASTM quality control standards]

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Category:Design for X

Category:Quality management

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