CFR > Title 7 - Agriculture > SUBTITLE B—Regulations of the Department of Agriculture > CHAPTER I—AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (parts 27 to 206) > SUBCHAPTER A—COMMODITY STANDARDS AND STANDARD CONTAINER REGULATIONS (parts 27 to 44) > PART 42—STANDARDS FOR CONDITION OF FOOD CONTAINERS > SUBPART E—Miscellaneous (§42.140 to §42.143) > 42.140—Operating Characteristic (OC) curves for on-line sampling and inspection.

42.140—Operating Characteristic (OC) curves for on-line sampling and inspection.

(a) This section contains the Operating Characteristic (OC) curve for each of the sampling plans given in Tables I, I-A, II, II-A, III, and III-A. The OC curve and the corresponding sampling plans are listed by AQL.
(b) Different acceptance and rejection criteria are provided for each AQL. The criteria for each AQL must be obtained from the applicable sampling plan tables.
(c) The curves show the ability of the various sampling plans to distinguish between good and bad lots. This can be illustrated by examining OC curve 6 for an AQL of 0.25 defects per hundred units in the Reduced and Normal Inspection Plans. If the quality of the lots submitted for inspection is poorer than the AQL of 0.25 defects per hundred units, fewer lots will be accepted. For example, OC curve 6 shows that when the quality of lots submitted for inspection is 1.0 defects per hundred units, only 26 percent of the lots are expected to be accepted. Conversely when the quality of the lots submitted for inspection is better than the AQL of 0.25 defects per hundred units, most lots are expected to be accepted. For example, the same OC curve 6 shows that when the quality of lots submitted for inspection is 0.10 defects per hundred units, about 99 percent of the lots are expected to be accepted.
(d) The table of sampling plans that correspond to OC curve 6 can be found over the curves for an AQL of 0.25 defects per hundred units in the Reduced and Normal Inspection Plan. An examination of this table reveals that there is one single and one double sampling plan that have OC curves comparable to OC curve 6. The first plan listed is a single plan requiring the inspection of 500 individual containers. Under this plan the lot is accepted as meeting the requirements for an AQL of 0.25 if there are 3 or less defects in the sample or rejected if there are 4 or more defects in the sample.
(e) The next plan that is listed in the column headed 6 for an AQL of 0.25 is a double sampling plan that requires the initial inspection of 228 individual containers. The lot will be accepted as meeting the requirements of an AQL of 0.25 if there are no defects in the sample, and rejected if there are 3 or more defects in the sample. In the event that the number of defects is between the acceptance (0) and rejection (3) numbers, additional containers must be inspected. In this case, the table indicates that a total of 516 containers must be inspected before a decision can be made to either accept or reject the lot. This will require the inspection of 288 more containers (516 − 228 = 288).

Code of Federal Regulations

If there are 3 or less defects in the total sample, the lot will be accepted. If there are 4 or more defects in the total sample, the lot will be rejected. The other double sampling plans operate in a similar manner with the only differences being the sample sizes and acceptance and rejection numbers.
Code of Federal Regulations 209
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=0.15 Defects per Hundred Units
[Sampling plans—AQL=0.15]
Comparable sampling plans Identification number of OC curve R1 nc Ac Re R2 nc Ac Re R3 nc Ac Re R4 nc Ac Re N4 nc Ac Re N5 nc Ac Re N6 nc Ac Re N7 nc Ac Re N8 nc Ac Re
Single 29 1 2 84 1 2 126 0 1 315 1 2 168 1 2 264 1 2 500 2 3 800 3 4 1,250 4 5
Double 18 0 2 36 0 2 120 0 2 174 0 2 252 0 3 456 0 4
36 1 2 96 1 2 180 1 2 336 1 2 540 2 3 864 3 4
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

Code of Federal Regulations 210
[Please see PDF for image: EC02SE91.001 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=0.15 Defects per Hundred Units
[Sampling plans—AQL=0.15]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re
Single 264 0 1 500 1 2 800 2 3 1,250 3 4
Double 360 0 2 456 0 3 576 0 3
516 1 2 864 2 3 1,296 3 4
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.002 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=0.25 Defects per Hundred Units
[Sampling plans—AQL=0.25]
Comparable sampling plans Identification number OC curves R1 nc Ac Re N2 nc Ac Re R3 nc Ac Re N and R4 nc Ac Re N and R5 nc Ac Re N6 nc Ac Re N7 nc Ac Re
Single 29 1 2 84 0 1 84 1 2 168 1 2 315 2 3 500 3 4 800 4 5
Double 18 0 2 36 0 2 120 0 2 168 0 3 228 0 3
18 1 2 96 1 2 180 1 2 348 2 3 516 3 4
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.003 ]
Tightened Inspection Plans—Sampling Plans and Operation Characteristics (OC) Curves for AQL=0.25 Defects per Hundred Units
[Sampling plans—AQL=0.25]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 0 1 315 1 2 500 2 3 800 3 4 1,250 4 5
Double 168 0 2 228 0 3 456 0 4
348 1 2 516 2 3 864 3 4
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.004 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=0.50 Defects per Hundred Units
[Sampling plans—AQL=0.50]
Comparable sampling plans Identification number of OC curves R1 nc Ac Re N and R2 nc Ac Re N and R3 nc Ac Re N and R4 nc Ac Re N5 nc Ac Re N6 nc Ac Re
Single 29 1 2 84 1 2 168 2 3 315 3 4 500 5 6 800 7 8
Double 18 0 2 36 0 2 120 0 3 168 0 4 228 0 5
36 1 2 96 1 2 180 2 3 348 3 4 516 5 6
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.005 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=0.50 Defects per Hundred Units
[Sampling plans—AQL=0.50]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 1 2 315 2 3 500 3 4 800 4 5 1,250 6 7
Double 120 0 2 168 0 3 228 0 3 456 1 5
180 1 2 348 2 3 516 3 4 864 4 5
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.006 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=1.00 Defects per Hundred Units
[Sampling plans—AQL=1.00]
Comparable sampling plans Identification number of OC curves R1 nc Ac Re N and R2 nc Ac Re N and R3 nc Ac Re N and R4 nc Ac Re N5 nc Ac Re N6 nc Ac Re
Single 29 1 2 84 2 3 168 4 5 315 6 7 500 9 10 800 13 14
Double 18 0 2 36 0 3 120 2 5 168 1 5 228 2 7
36 1 2 96 2 3 180 4 5 348 7 8 516 9 10
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.007 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=1.00 Defects per Hundred Units
[Sampling plans—AQL=1.00]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 2 3 315 3 4 500 5 6 800 7 8 1,250 10 11
Double 120 0 3 168 0 4 228 0 5 456 2 6
180 2 3 348 3 4 516 5 6 864 8 9
nc=Cumulative sample sizeAc=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.008 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=1.50 Defects per Hundred Units
[Sampling plans—AQL=1.50]
Comparable sampling plans Identification number of OC curves R1 nc Ac Re N and R2 nc Ac Re N and R3 nc Ac Re N and R4 nc Ac Re N5 nc Ac Re N6 nc Ac Re
Single 29 1 2 84 3 4 168 5 6 315 8 9 500 12 13 800 18 19
Double 18 0 2 36 0 4 120 2 6 168 2 7 228 3 9
36 1 2 96 3 4 180 5 6 348 9 10 516 12 13
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.009 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=1.50 Defects per Hundred Units
[Sampling plans—AQL=1.50]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 4 5 315 6 7 500 9 10 800 13 14 1,250 19 20
Double 120 2 5 168 1 5 228 2 7 456 5 10
180 4 5 348 7 8 516 9 10 864 14 15
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.010 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=2.50 Defects per Hundred Units
[Sampling plans—AQL=2.50]
Comparable sampling plans Identification number of OC curves R1 nc Ac Re N and R2 nc Ac Re N and R3 nc Ac Re N and R4 nc Ac Re N5 nc Ac Re N6 nc Ac Re
Single 29 2 3 84 4 5 168 7 8 315 13 14 500 18 19 800 27 28
Double 18 0 3 36 0 4 120 3 7 168 5 10 228 5 11
36 2 3 96 4 5 180 8 9 348 14 15 516 19 20
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.011 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=2.50 Defects per Hundred Units
[Sampling plans—AQL=2.50]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 5 6 315 8 9 500 12 13 800 18 19 1,250 26 27
Double 120 2 6 168 2 7 228 3 9 456 8 13
180 5 6 348 9 10 516 12 13 864 19 20
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.012 ]
Reduced and Normal Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=4.00 Defects per Hundred Units
[Sampling plans—AQL=4.00]
Comparable sampling plans Identification number of OC curves R1 nc Ac Re N and R2 nc Ac Re N and R3 nc Ac Re N and R4 nc Ac Re N5 nc Ac Re N6 nc Ac Re
Single 29 3 4 84 6 7 168 11 12 315 19 20 500 28 29 800 42 43
Double 18 1 3 36 0 5 120 6 10 168 7 13 228 8 17
36 4 5 96 7 8 180 12 13 348 21 22 516 29 30
nc=Cumulative sample size.Ac=Acceptance number.Re=Rejection number.

Code of Federal Regulations

[Please see PDF for image: EC02SE91.013 ]
Tightened Inspection Plans—Sampling Plans and Operating Characteristic (OC) Curves for AQL=4.00 Defects per Hundred Units




[Sampling plans—AQL=4.00]
Comparable sampling plans Identification number of OC curves 1 nc Ac Re 2 nc Ac Re 3 nc Ac Re 4 nc Ac Re 5 nc Ac Re
Single 168 7 8 315 13 14 500 18 19 800 27 28 1,250 41 42
Double 120 3