The Reliability Engineering Glossary
Reliability engineering and related fields use a vocabulary unique to our field of endeavor. For example, the term ‘reliability’ has the meaning of ‘trustworthy’ in everyday English use. For us, ‘reliability’ has a precise engineering definition.
Glossary description and plans
This glossary is meant to help us learn the language of reliability engineering. The category of ‘Terms’ is like a dictionary, including terms and their definitions as used by engineers. The category of ‘Methods’ is a listing of the techniques, tools, approaches, or concepts that may be found within a reliability plan. In the near future, we expect to expand the ‘Methods’ pages to include guidelines on use or application, examples, and additional references.
We also plan to expand the glossary to include formulas and failure mechanisms. Please let us know if there is another list of terms that should be added if you do not find a term that should be included or if you would like to recommend a change to an existing entry.
Method Categories
a
- Acceleration factor, stressThe acceleration factor due to an applied stress such as current density, electric field, temperature cycling or humidity. Read More
- Acceleration modelA mathematical relationship describing the a) the rate of a degradation mechanism or the time-to-failure, and b) the conditions or stresses that caused the degradation. Read More
- Acceptability constantA constant useful in acceptance sampling set depending on the acceptance quality limit specified value and the sample size. It is part of an acceptance sampling plan by variable as the criteria for lot acceptance. Read More
- Acceptability criteriaA limit or limits placed upon the degree of nonconformance permitted in material expressed in definitive operational terms. Read More
- Acceptable quality levelIn a continuing series of lots, a quality level that, for the purpose of sampling inspection, is the limit of a satisfactory process average. Read More
- Acceptable riskAn amount of risk that is less than or equal to the maximum tolerable risk and as low as reasonably practical. Risk that the appropriate acceptance authority is willing to accept without additional mitigation. Read More
- AcceptanceWhen using control charts or acceptance control charts, acceptance is a decision that the monitored process is operating in a satisfactory manner considering the plotted statistical measures. Read More
- Acceptance inspection100% or sampling inspection or series of inspections to determine the suitability of a lot of material for shipment or use. Read More
- Acceptance numberThe largest number of nonconformities or nonconforming items within a sample for acceptance sampling by attributes, permitting the acceptance of the lot as detailed in the acceptance sampling plan. Read More
- Acceptance quality limit (AQL)In acceptance sampling with a continuing series of submitted lots, it is a quality limit that defines the worst tolerable process average. Read More
- Acceptance samplingInspection of a sample from a lot to decide whether to accept that lot. There are two types: attributes sampling and variables sampling. In attributes sampling"," the presence or absence of a characteristic is noted in each of the units inspected. In variables sampling"," the numerical(...) Read More
- Acceptance sampling inspection systemA collection of acceptance sampling plans or schemes along with criteria for the selection of appropriate plan or schemes for given situations. (see Inspection and the following entries for the many variations of acceptance sampling inspection types) Read More
- Acceptance sampling planA specific plan that indicates the sampling sizes and associated acceptance or non-acceptance criteria to be used. In attributes sampling, for example, there are single, double, multiple, sequential, chain, and skip-lot sampling plans. In variables sampling, there are single, double, and(...) Read More
- Acceptance sampling procedureThe operational requirements/instructions for a particular acceptance sampling plan, including the method of selection, withdrawal, and preparation of samples. Read More
- Acceptance sampling schemeA combination of acceptance sampling plans along with switching rules to guide using one plan then another. Read More
- Acceptance testA test conducted under specified conditions by or on behalf of the customer, using delivered or deliverable items, to determine whether or not the item satisfies specified requirements. Includes acceptance of first production units. Read More
- Acceptance valueUsed with an acceptance sampling plan by variables as a limiting value of the sample average that enables the meeting of the acceptability constant. Read More
- Accepted reference valueAn agreed-upon value that serves as a reference for comparison. The value may be derived as - A scientific principle based theoretical or established value; An experimental work of a national or international organization assigned or certified value; A collaborative experimental work of an(...) Read More
- AccessTo gain entry to, or control of, a part of a system. Read More
- AccessibilityA measure of the relative ease of admission to the areas of an item for the purpose of operation or maintenance. Read More
Leave a Reply