7 C.F.R. § 43.103 – Purpose and scope.

(a) This subpart contains selected single and double sampling plans for inspection by attributes. They are to serve as a source of plans for developing sound specifications, standards, or sampling and inspection procedures.
(b) The sampling plans of this subpart and corresponding operating characteristic curves are indexed by acceptable quality level, AQL. The AQL's expressed in percent defectives or defects per hundred units are:
0.065 0.40 2.5 8.5
0.10 0.65 4.0 10.0
0.15 1.0 5.0 12.5
0.25 1.5 6.5 15.0