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sample size, the lot fails the requirement.

(c) If in the conduct of on-line inplant inspection of a product covered by a grade standard which does not contain sampling plans, the sample is examined before the lot size is known and the number of sample units exceeds the prescribed sample size for such lot, but does not equal any of the prescribed larger sample sizes, the lot may be deemed to meet or fail a specific requirement in accordance with the following procedure:

(1) If the number of deviants (as defined in connection with the specific requirement) in the nonprescribed sample does not exceed the acceptance number of the next smaller sample size, the lot meets the requirement;

(2) If the number of deviants (as defined in connection with the specific requirement) in the nonprescribed sample equals the acceptance number prescribed for the next larger sample size, additional sample units shall be selected to increase the sample to the next larger prescribed sample size;

(3) If the number of deviants (as defined in connection with the specific requirement) in the nonprescribed sample exceeds the acceptance number prescribed for the next larger sample size, the lot fails the requirement.

(d) In the conduct of on-line in-plant inspection, sampling may be performed on a time interval basis. The sampling frequency shall be specified in an applicable grade standard or other procedural instruction approved by the Administrator.

(e) In the event that the lot compliance determination provisions of a

standard or specification are based on the number of specified deviations instead of deviants the procedures set forth in this section may be applied by substituting the word "deviation" for the word "deviant" wherever it appears.

(f) Sampling plans referred to in this section are those contained in Tables I, II, III, IV, and V and (g)(1) and (g)(2) of this section which follow or any other plans which are applicable. For processed products not included in these tables, the minimum sample size shall be the exact number of sample units prescribed in the table, container group, and lot size that, as determined by the inspector, most closely resembles the product, type, container, size and amount of product to be sampled. The maximum sample size in tables I, II, III, IV, V, (g)(1), (g)(2) and processed products not included in these tables is 29 sample units.

(g)(1) Sampling plan for dried figs. For each 10,000 pounds (or fraction of 10,000 pounds) of product-6 sample units of approximately 35 figs each accumulated into 1 composite (at least 200 figs). Each composite will be examined separately, and all must meet the requirement for the U.S. Grade.

(2) Sampling plan for dried fruits other than dates and figs. For each 15,000 pounds (or fraction of 15,000 pounds) of product-sample units of approximately 16 ounces each accumulated into 1 composite (at least 100 ounces) Each composite will be examined separately and all must meet the requirements for the U.S. Grade.

TABLE CANNED OR SIMILARLY PROCESSED FRUITS, VEGETABLES, AND PRODUCTS CONTAINING UNITS OF SUCH SIZE AND CHARACTER AS TO BE READILY SEPARABLE

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TABLE-CANNED OR SIMILARLY PROCESSED FRUITS, VEGETABLES, AND PRODUCTS CONTAINING UNITS OF SUCH SIZE AND CHARACTER AS TO BE READILY SEPARABLE-Continued

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Under on-line in-plant inspection, a 5% overrun in number of containers may be permitted by the inspector before going to the next larger sample size.

2 When a standard sample size is not specified in the U.S. grade standards, the sample units for the various container size groups are as follows: Groups 1, 2, and 31 container and its entire contents. Group 4 that approximately 2 pounds of product. When determined by the inspector that a 2-pound sample unit is inadequate, a larger sample unit may be substituted.

TABLE II-FROZEN OR SIMILARLY PROCESSED FRUITS, VEGETABLES, AND PRODUCTS CONTAINING UNITS OF SUCH SIZE AND CHARACTER AS TO BE READILY SEPARABLE

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* Under on-line in-plant inspection, a 5% overrun in number of containers may be permitted by the inspector before going to the next larger sample size.

2 When a standard sample unit size is not specified in the U.S. grade standards, the sample units for the various container size groups are as follows: Groups 1 and 2-1 container and its entire contents. Group 3 containers up to 10 lbs.approxi mately 3 pounds of product. When determined by the inspector that a 3-pound sample unit is inadequate, a larger sample unit or 1 or more containers and their entire contents may be substituted for 1 or more sample units of 3 lbs.

TABLE III-CANNED, FROZEN, OR OTHERWISE PROCESSED FRUITS, VEGETABLES, RELATED PRODUCTS OF A COMMINUTED, FLUID OR HOMOGENEOUS STATE

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'Under on-line in-plant inspection, a 5% overrun in number of containers may be permitted by the inspector before going to the next larger sample size.

2 When a standard sample size is not specified in the U.S. grade standards, the sample units for the various container size groups are as follows: Groups 1, 2, and 31 container and its entire contents. A smaller sample unit may be substituted in Group 3 at the inspector's discretion. Group 4 approximately 16 ounces of product. When determined by the inspector that a 16 ounce sample unit is inadequate, a larger sample unit may be substituted.

TABLE IV-DEHYDRATED (LOW-MOISTURE) FRUITS, AND VEGETABLES

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'Under on-line in-plant inspection, a 5% overrun in number of containers may be permitted by the inspector before going to the next larger sample size.

2 When a standard sample unit size is not specified in the U.S. grade standards, the sample units for the various container size groups are as follows: Group 1-1 container and its entire contents. Groups 2 and 31 container and its entire contents or a smaller sample unit when determined by the inspector to be adequate.

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Under on-line in-plant inspection, a 5% overrun in number of containers may be permitted by the inspector before going to the next larger sample size.

2 Samples consist of 25 ounce sample units, each of which may be a composite of product from a sufficient number of individual containers from 1 case to make up the weight. When previous inspection results from a particular source so indicate, 1 composite sample of 25 ounces of product samples of 25 ounces each may be formed from thed from the 3 sample units in the smallest sample size, and 2 composite from the 6 sample units in the next to smallest sample size. Sample units in larger sample sizes may not be further composited.

[38 FR 25166, Sept. 12, 1973; 38 FR 26903, Sept. 27, 1973. Redesignated at 42 FR 32514, June 27, 1977 and at 46 FR 63203, Dec. 31, 1981, and amended at 51 FR 20439, June 5, 1986]

§ 52.38a Definitions of terms applicable to statistical sampling.

(a) Terms applicable to both on-line inspection and lot inspection.

(1) Acceptable Quality Level (AQL). The maximum percent of defective units of product or the maximum number of defects per hundred units of product which are acceptable as a process average. At the AQL's contained in the statistical sampling plans of this subpart, production has a probability of acceptance ("Pa") of approximately 95 percent.

(2) Acceptance sampling. Sampling inspection in which decisions are made to accept or reject product.

(3) Attributes. A method of measurement whereby units of product are examined for the presence or absence of specified characteristics in each unit in the sample.

(4) Defect. Any nonconformance of a unit of product from specified requirements of a single quality characteristic. Defects are classed as "minor," "major," "severe" or "critical" depending upon the severity and undesirability of the defect.

(5) Defective. A unit of product that has one or more defects.

(6) Inspection by attributes. Inspection whereby a unit of product is classified as defective or nondefective or the number or defects in the unit of product is counted.

(7) Standard sample unit size. A specified amount of product to be used for inspection.

(b) Terms applicable to on-line inspection only.

(1) Basic inspection period. A specified period of consecutive production designated for on-line inspection.

(2) Cumulative Sum Sampling (CuSum) Plan. An on-line sampling plan that accumulates the number of defects (or defectives), which exceed the sample unit tolerance (“T”), in a series of consecutive samples. Terms specific to the CuSum sampling plan are:

(i) Acceptance limit (“L”). The maximum accumulation of defects (or defectives) allowed to exceed the sample unit tolerance (“T”) in any sample unit or consecutive group of sample units.

(ii) CuSum value. The accumulated number of defects (or defectives) that exceed the sample unit tolerance ("T").

(iii) Sample unit tolerance ("T"). The allowable number of defects (or defectives) in any sample unit.

(iv) Starting value ("S"). The initial CuSum value used to begin a CuSum sampling plan.

(3) On-line sampling inspection. The random selection and subsequent inspection of sample units from a production line.

(4) Probability of acceptance ("Pa"). The probability that a portion of production, with a given level of quality, will be accepted. In on-line sampling inspection, the probability of acceptance of any portion of production depends on the sample results obtained from the preceding portions. The probability of acceptance values associated with these procedures are the values which would be expected if a large number of sample units are to be inspected. For the CuSum plans referenced in these procedures, the probability of acceptance at the Acceptable Quality Level (AQL) is approximately 95 percent. The starting value ("S") associated with each CuSum plan helps to make the probability of acceptance

of the first portions of production of a basic inspection period as close as possible to 95 percent.

(c) Terms applicable to lot inspection only.

(1) Acceptance number. The largest number of defects (or defectives) in the sample that will permit acceptance of the inspection lot.

(2) Inspection lot. Any number of containers of the same size and type which contain a processed product of the same type and style, manufactured or processed under essentially the same conditions, offered for inspection and acceptance at one time.

(3) Probability of acceptance ("Pa"). The probability that an inspection lot, with a given level of quality, will be accepted.

[43 FR 10540, Mar. 14, 1978. Redesignated at 46 FR 63203, Dec. 31, 1981]

$52.38b Statistical

sampling procedures for on-line inspection by attributes of processed fruits and vegetables.

(a) General. The Cumulative Sum Sampling Plan, hereinafter referred to as "CuSum," shall be used as the online sampling plan for attributes standards under the following conditions.

(1) The producer has designated the intended grade for the basic inspection period prior to the start of production.

(2) Inspection of the product shall be made during the basic inspection period at a point after which all product characteristics, subject to inspection, are fixed and will not be subject to change during final packaging.

(3) A shift to CuSum sampling plans from lot sampling plans during a basic inspection period is not permitted (or vice versa).

(b) Sampling rate/frequency. The minimum number of standard sample units to be drawn at random shall be determined by the applicable sampling procedure as approved by the Administrator.

(c) Determining CuSum values. At the beginning of the basic inspection period, the CuSum value is set equal to the starting value ("S") for the specified CuSum plan. The CuSum value is then determined for each consecutive sample unit as follows:

(1) Add the number of defects (or defectives) for the present sample unit to the CuSum value of the previous sample unit.

(2) Subtract the sample unit tolerance ("T").

(3) The CuSum value is reset in the following situations. However, determine compliance with the designated grade (see paragraph (d) of this section) prior to resetting the CuSum value:

(i) Reset the CuSum value to zero (0) if the CuSum value is less than zero (0).

(ii) Reset the CuSum value to the acceptance limit ("L") if the CuSum value exceeds the acceptance limit ("L").

(d) Determining compliance for a designated grade. (1) A portion of production meets the designated grade if the CuSum value, calculated from the sample unit representing that portion, is equal to or less than the acceptance limit ("L") for all classes of defects.

(2) A portion of production fails the designated grade if the CuSum value, calculated from the sample unit representing that portion, exceeds the acceptance limit (“L”) for one or more classes of defects.

(e) Evaluation of production failing a designated grade. Production failing a designated grade shall be reevaluated by procedures approved by the USDA.

(f) Assigning a grade. (1) All similarly identified (e.g., codes, subcodes, etc.) production will be assigned the same grade.

(2) The grade assigned to similarly identified production will be the lowest grade assigned to any portion of that similarly identified production.

(g) Redesignation of producer's intended grade. If the intended grade is redesignated during a basic inspection period, a new CuSum sampling plan shall be instituted for each class of defects (or defectives).

(h) Cumulative Sum Sampling (CuSum) Plans for processed fruits and vegetables. (1) Tables VI through X contain the CuSum sampling plans for each of five different standard sample unit sizes. The plans within each table are listed according to increasing values of Acceptable Quality Levels (AQL's).

(2) AQL values of 10.0 or less may be expressed either in "defects per hundred units" or in “percent defective

units." The same sampling plans are used for both. Separate sampling plans must be used for AQL values greater than 10.0.

(3) These tables also provide the quality levels associated with 50 percent and 10 percent probabilities of acceptance for each of the plans. These quality levels are expressed in the same units as the corresponding AQL values.

(4) A separate CuSum sampling plan is chosen for each class of defects (or defectives) by first specifying the desired AQL and then selecting the appropriate standard sample unit size. The quality levels associated with 50 percent and 10 percent probabilities of acceptance may be used as guides to help determine a suitable standard sample unit size.

TABLE VI-CUSUM SAMPLING PLANS
[Standard sample unit size=13]

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