42.107—Lot acceptance criteria.
(a)
The acceptability of the lot is determined by relating the number and class of defects enumerated on the worksheet to the acceptance and rejection numbers shown in §§ 42.109 through 42.111 for the respective sample size and Acceptable Quality Level (AQL).
| Defect class | AQL at origin inspection | AQL at other than origin inspection |
|---|---|---|
| Critical | 0.25 | 0.25 |
| Major | 1.5 | 2.5 |
| Total | 6.5 | 10.0 |
(c)
Refer to the appropriate sample size and AQL and compare the number of defects found in the sample with the acceptance (Ac) and rejection (Re) numbers in the sampling plan.
(1)
Accept the lot after examining the single sample or first sample of a double sampling plan when all of the following conditions are met:
(i)
The number of critical defects does not exceed the applicable acceptance number (Ac) for critical defects, and
(ii)
The number of major defects does not exceed the applicable acceptance number (Ac) for major defects, and
(iii)
The total number of critical, major, and minor defects does not exceed the applicable acceptance number (Ac) for total defects.
(2)
Reject the lot after examining the single sample or first sample of a double sampling plan when any one or more of the following conditions occur:
(i)
The number of critical defects equals or exceeds the applicable rejection number (Re) for critical defects, or
(ii)
The number of major defects equals or exceeds the applicable rejection number (Re) for major defects, or
(iii)
The total number of critical, major, and minor defects equals or exceeds the applicable rejection number (Re) for total defects.
(3)
If the lot can neither be accepted nor rejected on the first sample, when a double sampling plan is used, select and examine the prescribed second sample. Accept the lot if the accumulated defects of the first and second sample meet conditions of paragraph (c)(1) of this section, otherwise, reject the lot.