Statistical Acceptance Sampling Protocols for Paperboard Package Lot Verification
Statistical lot verification protects packaging buyers by tying standardized sample testing directly to batch acceptance quality limits and contract settlement terms.
Lot Tolerance Percent Defective
Reject Boundary
The highest percentage of defective items in a batch that a buyer is willing to accept is defined as a specific threshold in quality control agreements. This value, known as lot tolerance percent defective, represents the point at which the quality of a lot becomes unacceptable.
Statistical Risk
In packaging procurement, this parameter is used to design sampling plans that protect the buyer from accepting poor-quality material. If a batch of cartonboard has a defect rate higher than this threshold, the sampling plan should reject the lot with a high probability. This probability is typically set at ninety percent, meaning there is only a ten percent chance of accepting a lot of such low quality.
Contract Specification
Setting this limit requires a balance between the cost of inspection and the risk of using defective packaging on high-speed filling lines. A very low percentage threshold requires larger sample sizes, which increases the testing time and cost for the quality control team. However, it prevents defective folding cartons from causing jams or product damage during the filling process.
This parameter is negotiated and defined in the quality agreement between the converter and the board manufacturer to establish a clear standard for batch acceptance.