The inspection level determines the relation between the batch size and sample size.

Levels I, II, III, IV, V are general inspection levels:

• Level IV is designated as normal.
• Level V requires a larger amount of inspection than level IV, and is used when more discrimination (or power) is needed.
• Levels I, II, III require less inspection than level IV, and are used when reduced sampling costs are required and a lower level of discrimination (or power) can be tolerated.