An Acceptable Quality Level (AQL) is the maximum number of errors, defects, or Contamination at which data are considered usable.

Acceptance Criteria
Specific limits placed on the characteristic of an item, process, or service, as defined in a requirements document, to be considered satisfactory for use. See also Performance Criteria.

Accreditation
The process by which an agency or organization evaluates and recognizes a laboratory as meeting certain predetermined qualifications or standards, thereby accrediting the laboratory.