Quality Control

The processes a company or organization uses to test products to ensure that they are not defective. Quality control operatives may investigate the procedures used to make a product, the knowledge of employees or even intangibles like company morale. Quality control is distinguished from quality assurance in that quality control tests for errors while quality assurance seeks to put in place systems to ensure that the errors do not happen in the first place. See also: Quality.

quality control

the task of ensuring that the QUALITY of a product or service meets specified performance criteria. Quality control involves a number of activities, in particular:

interpretation of PRODUCT SPECIFICATIONS;
INSPECTION of products at each stage of production, including SAMPLING procedures to select items for testing and the use of testing equipment to check the performance of components or products and detect those that are defective. The results of such tests enable production operations to be modified quickly, for example by changing machine settings, to prevent further defectives being made and thereby saving on rectification costs or the later processing costs of items which would eventually have to be scrapped;
cooperation with design, marketing, production and research and development over improvements in product quality;
undertaking periodic quality audits to review the effectiveness of quality control procedures. See TOTAL QUALITY MANAGEMENT, PRODUCTION CONTROL, QUALITY ASSURANCE, FISHBONE CHART, QUALITY CIRCLE, SCRAP, CONTROL CHART, FAILURE COSTS, NORMAL CURVE, SAMPLING, ACCEPTANCE SAMPLING, CONTROL COSTS, LOT TOLERANCE PERCENTAGE DEFECTIVE, QUALITY FUNCTION DEPLOYMENT, QUALITY LOSS FUNCTION.

quality control

a discipline concerned with improving the QUALITY of goods and services produced. The object of quality control is to prevent faulty components or finished goods from being produced, and it uses a variety of devices to help achieve this aim. Techniques of statistical sampling and testing can be used to identify faulty materials and products. Statistical variability limits can be used to ensure, for example, that machines are continuing to hold their tolerances in producing goods. QUALITY CIRCLES can be employed to involve work-groups in the task of quality assurance by generating discussion about the cause of quality problems and how workers themselves can deal with such problems. See also PRODUCTIVITY, PRODUCT PERFORMANCE, PRODUCT DIFFERENTIATION.