MIL-PRF-38535K
APPENDIX D
D.4.2.1 Sample size. The sample size for each subgroup shall be determined from table D-I or D-II and shall meet
the specified sample size series. The manufacturer may, at their option, select a sample size greater than that
required; however, the number of failures permitted shall not exceed the acceptance number associated with the
chosen sample size in table D-I or D-II. In table D-II, the sample size series column to be used for sample size
determination shall be that given in the lot size column which is nearest in value of the actual size of the submitted lot,
except that if the actual lot size is midway between two of the lot sizes given in the table, either of the bounding lot
size columns may be used at the manufacturer's option. If, in table D-II, the appropriate lot size column does not
contain a sample size series value equal to or less than the specified sample size series value, 100 percent
inspection shall be used. In table D-II, the sample size series value in the appropriate lot size column that is
numerically closest to the specified sample size series value shall be used to determine the sample size.
D.4.2.2 Acceptance procedure. For the first sampling, an acceptance number shall be chosen and the associated
number of sample devices for the specified sample series selected and tested (see D.4.2.1). If the observed number
of defectives from the first sample is less than or equal to the preselected acceptance number, the lot shall be
accepted. If the observed number of defectives exceeds the preselected acceptance number, an additional sample
may be chosen such that the total sample complies with D.4.2.3. The table (D-I or D-II), which is used for the first
sampling of a given inspection lot for a given subgroup shall be used for any and all subsequent samplings for the
same lot and subgroup for each lot submission.
D.4.2.3 Additional sample. The manufacturer may add an additional quantity to the initial sample, but this may be
done only once for any subgroup and is limited to the initial sample (e.g., does not apply to resubmitted lots after
initial failure). The added samples shall be subjected to all the tests within the subgroup. The total sample size
(initial and added samples) shall be determined by the new acceptance number selected from table D-I or D-II).
D.4.2.4 Multiple criteria. When one sample is used for more than one acceptance criterion, the entire sample for a
subgroup shall be used for all criteria within the subgroup. In table D-I, the acceptance number shall be that one
associated with the largest sample size in the appropriate sample size series column which is less than or equal to
the sample size used. In table D-II, the acceptance number shall be that one associated with the specified samples
size series, in the appropriate lot size column, for the sample size used.
D.4.2.5 One hundred percent inspection. Inspection of 100 percent of the lot shall be allowed, at the option of the
manufacturer, for any or all subgroups other than those which are called "destructive". If the observed percent
defective for the inspection lot exceeds the specified samples size series value, the lot shall be considered to have
failed the appropriate subgroup(s). Resubmission of lots tested on a 100 percent inspection basis shall also be on a
100 percent inspection basis only and in accordance with the tightened inspection sample series value and other
requirements of A.4.3.3.1.
D.4.2.6 Tightened inspection. Tightened inspection shall be performed by testing to the criteria of the next sample
size series value lower than that specified in the series 1, 1.5, 2, 3, 5, and 7 times 10n, where n is an integral number.
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ACTEL [ Actel Corporation ]
