Acceptable Quality Level (AQL)

Acceptable Quality Level (AQL) is the minimum quality below which a product or service is defined to have failed.

In a sampling plan it is the routinely accepted quality level. An AQL of 95% means the sampling plan will accept 95% of the time.

There has been significant debate about AQL. On one side, it is argued that if you accept a given level and do not constantly strive to improve quality, then your competitors will overtake you and your customer come to see you as producing poor quality. On the other hand, it may be said that 'gold plating' in providing higher quality than is needed is more costly and time-consuming, which can be damaging for both shareholders and customers who want 'good enough', cheaply and quickly.

AQL is sometimes also referred to as Assured Quality Level.

Rejectable Quality Level (RQL) identifies the test failure level below which a product or service will be rejected.

In sampling plan, it is the routinely rejected quality level. This is typically between 0.01% and 10%, depending on the criticality of the items being accepted and the natural probability of failure. In a sampling plan with a RQL of 10%, it will accept 10% of the time (and reject 90% of the time).

RQL is equivalent to Lot Tolerance Percent Defective (LTPD) and Unacceptable Quality Level (UQL) and Limiting Quality (LQ).

Acceptable Quality Level (AQL)

See also: