Double Sampling Plan.

A number of sample units equal to the first sample size given by the plan shall be inspected. If the number of defectives found in the first sample is equal to or less than the first acceptance number, the lot or batch shall considered acceptable. If the number of defectives found in the first sample is equal to or greater than the first rejection number, the lot or batch shall be rejected. If the number of defectives found in the first sample is between the first acceptance and rejection numbers, a second sample of the same size shall be inspected. the number of defectives found in the first and second samples shall be accumulated. If the cumulative number of defectives is equal to or less than the second acceptance number,the lot or batch shall be considered acceptable. If the cumulative number of successive samples required to reach a decision my be as seven.
http://www.inspectionchina.com/MIL-STD-105E-ENERAL-REQUIREME...


Normal inspection:
The number of items inspected as specified by the sampling inspection plan at the outset; if the quality of the product improves, the number of units to be inspected is reduced; if quality deteriorates, the number of units inspected is increased.
http://www.answers.com/topic/normal-inspection


See Page 64 of this book
http://books.google.com/books?id=r5rAVugG8isC&pg=PA64&lpg=PA...

http://books.google.com/books?id=SZcSLmahaG0C&pg=PA171&lpg=P...


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Note added at 3 hrs (2009-02-15 16:41:08 GMT)
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You may also refer to this bilingual glossary about quality acceptance at
http://www.hxen.com/word/changyong/2008-10-07/56287.html