Acceptable quality limit
Encyclopedia
The acceptable quality limit (AQL) is the worst tolerable process average in percentage or ratio, that is still considered acceptable: that is, it is at an acceptable quality level. Closely related terms are the rejectable quality limit and level (RQL).
In a quality control
procedure, a process is said to be at an acceptable quality level if the appropriate statistic used to construct a control chart
does not fall outside the bounds of the acceptable quality limits. Otherwise, the process is said to be at a rejectable control level.
The usage of the abbreviation AQL for the term Acceptable Quality Level has recently been changed in the standards issued by at least one national standards organization
(ANSI
/ASQ
) to relate to the term Acceptance Quality Level. It is unclear whether this interpretation will be brought into general usage, but the underlying meaning remains the same.
An acceptable quality level is an inspection standard describing the maximum number of defects that could be considered acceptable during the random sampling of an inspection. The defects found during inspection are sometimes classified into three levels: critical, major and minor. Critical defects are those that render the product unsafe or hazardous for the end user or that contravene mandatory regulations. Major defects can result in the product's failure, reducing its marketability, usability
or saleability
. Lastly, minor defects do not affect the product's marketability or usability, but represent workmanship
defects that make the product fall short of defined quality standards. Different companies maintain different interpretations of each defect type. In order to avoid argument, buyers and sellers agree on an AQL standard, chosen according to the level of risk
each party assumes, which they use as a reference during pre-shipment inspection.
In a quality control
Quality control
Quality control, or QC for short, is a process by which entities review the quality of all factors involved in production. This approach places an emphasis on three aspects:...
procedure, a process is said to be at an acceptable quality level if the appropriate statistic used to construct a control chart
Control chart
Control charts, also known as Shewhart charts or process-behaviour charts, in statistical process control are tools used to determine whether or not a manufacturing or business process is in a state of statistical control.- Overview :...
does not fall outside the bounds of the acceptable quality limits. Otherwise, the process is said to be at a rejectable control level.
The usage of the abbreviation AQL for the term Acceptable Quality Level has recently been changed in the standards issued by at least one national standards organization
Standards organization
A standards organization, standards body, standards developing organization , or standards setting organization is any organization whose primary activities are developing, coordinating, promulgating, revising, amending, reissuing, interpreting, or otherwise producing technical standards that are...
(ANSI
American National Standards Institute
The American National Standards Institute is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organization also coordinates U.S. standards with international...
/ASQ
American Society for Quality
American Society for Quality , formerly known as American Society for Quality Control , is a knowledge-based global community of quality control experts, with nearly 85,000 members dedicated to the promotion and advancement of quality tools, principles, and practices in their workplaces and in...
) to relate to the term Acceptance Quality Level. It is unclear whether this interpretation will be brought into general usage, but the underlying meaning remains the same.
An acceptable quality level is an inspection standard describing the maximum number of defects that could be considered acceptable during the random sampling of an inspection. The defects found during inspection are sometimes classified into three levels: critical, major and minor. Critical defects are those that render the product unsafe or hazardous for the end user or that contravene mandatory regulations. Major defects can result in the product's failure, reducing its marketability, usability
Usability
Usability is the ease of use and learnability of a human-made object. The object of use can be a software application, website, book, tool, machine, process, or anything a human interacts with. A usability study may be conducted as a primary job function by a usability analyst or as a secondary job...
or saleability
Saleability
Saleability is a technical analysis term used to compare performances of different trading systems or different investments within one system. Note, it is not simply another word for profit...
. Lastly, minor defects do not affect the product's marketability or usability, but represent workmanship
Workmanship
Workmanship is an EP by Joy Electric released exclusively as a 7" vinyl record album through Republic of Texas Recordings. Workmanship was completely written and recorded by Ronnie Martin on a Minimoog Voyager synthesizer...
defects that make the product fall short of defined quality standards. Different companies maintain different interpretations of each defect type. In order to avoid argument, buyers and sellers agree on an AQL standard, chosen according to the level of risk
Risk
Risk is the potential that a chosen action or activity will lead to a loss . The notion implies that a choice having an influence on the outcome exists . Potential losses themselves may also be called "risks"...
each party assumes, which they use as a reference during pre-shipment inspection.