Acceptance sampling can determine whether an entire lot of product should be accepted for use or rejected. With variables, each plan will evaluate a single measured characteristic, such as thickness, concentration, or surface roughness, against at least one specification.

With Minitab you can:

·    Create a sampling plan – determine how many units to inspect from a lot and determine how many defects/defective units are allowed.

·    Compare various sampling plans – see the effects of varying sample size and critical distance on the plan risk.

·    Accept or reject a particular lot based on actual sample data.

Acceptance sampling does not improve the quality of the process in any way and is not a substitute for good quality control processes, but it is useful as a decision-making tool for accepting or rejecting products and services

A camera assembly manufacturer receives camera lenses in shipments of 3,600 lenses several times a day. The quality team has implemented a sampling plan to inspect the lenses to determine whether they are acceptable for use. From the lot of 3,600 lenses, the team sets the acceptable quality level (AQL) to 100 defectives per million and the rejectable quality level (RQL) to 600 defectives per million.

Using a producer's risk (alpha) of 0.05 and a consumer's risk of 0.10, Minitab determines that an appropriate sampling plan is to inspect 259 lenses. The team randomly selects and measures lens thickness for 259 lenses. They will either accept the entire lot or reject it based on the measurements.

The team wants to examine the risk involved with inspecting fewer lenses.