1.1This practice presents methodology for the setting of an upper confidence bound regarding a unknown fraction or quantity non-conforming, or a rate of occurrence for nonconformities, in cases where the method of attributes is used and there is a zero response in a sample. Three cases are considered.

1.1.1The sample is selected from a process or a very large population of discrete items, and the number of non-conforming items in the sample is zero.

1.1.2A sample of items is selected at random from a finite lot of discrete items, and the number of non-conforming items in the sample is zero.

1.1.3The sample is a portion of a continuum (time, space, volume, area etc.) and the number of non-conformities in the sample is zero.

1.2Allowance is made for misclassification error in this standard, but only when misclassification rates are well understood or known and can be approximated numerically.