Acceptance Number

The acceptance number is the highest number of nonconforming items that can be found in a sample for a lot to still be considered acceptable. This number is determined by statistical analysis and is based on the required quality level, lot size, and sample size.

The underlying premise of using an acceptance number is that it is okay to deliver a certain amount of poor quality to your customers, as long as it is within contractual parameters.

Keep in mind that meeting the acceptance number does not mean that a process is good. It simply means that the negotiators did a good job of convincing customers to accept poor quality. Always shoot to reduce the acceptance number. The goal should be zero defects.