Grand Lot--This lot consists of a number of sub-lots which possess the following characteristics:

SB 740-91-01

The selection of representative samples for inspection is dependent on a given lot's homogeneity. However, to ensure

practicality of storage inspections the lot sampled should be as large as possible. For this reason three lot types have

been defined for use as follows:

(1) Manufacturers Lot--This lot consists of a group of items, belonging to a uniform, pre-established (by

manufacturer) lot, batch, cure data, or control number. Further, as items are drawn from storage for field use, the

remaining items may be considered as either a lot unto themselves, or as deemed appropriate a sublot to a grand or

mixed lot.

(2) Grand Lot--This lot consists of a number of sub-lots which possess the following characteristics:

(a) Identical stock number, class, type, model

(b) Same manufacturer

(c)

Same period of manufacture

(d) Comparable storage history

(e) Identical packaging

(f)

No known significant difference in quality.

NOTE

The grand lot may be formed when complete analysis of all available data-including the conditions noted

above and the technical judgment of the surveillance teams--indicates the homogeneity of deteriorative

characteristics. The formation of a grand lot at a depot is only a paper transaction and does not require

any rewarehousing or reworking of material. Where such grand lots are formed and sampled for

inspection, reports of results must include a complete description of the grand lot composition in each

case. If samples drawn from the grand lot indicate heterogeneity of sub-lots comprising the grand lot, the

lot will be terminated, and manufacturer's lot sampling substituted.

(3) Mixed Lot--The mixed lot consists of one or more lots whose identification by manufacturer or lot number has

been lost, and relationship to other lots cannot be determined. An example of this is depot rollback, or repacks of

preserved materials. Several mixed lots may be grouped into grand lots if inspection data indicate that the lots possess

similar deteriorative characteristics.

e. Acceptable Quality Level (AQL). The Acceptable Quality Level (Storage Quality Level) is the maximum percent

defective (or the maximum number of defects per hundred units) that, for purposes of sampling inspection, can be

considered satisfactory. Table 2-4 (taken from MIL-STD-105) provides specific accept/reject criteria for designated

sample size and acceptable quality levels.

f. Shelf Life (SLC). The Shelf Life column contains a code describing the particular deterioration characteristics

versus time for an item of consideration. Specific definitions for the codes listed in this column are per AR 700-89 and are

defined in Table 2-5. Appendix C gives a separate listing of items identified with specific shelf-life codes for CECOM

materiel.

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