Non-Conformance Report
Meaning ~ Documentation instrument detailing specific deviations from technical or contractual standards during production to control resolution paths and costs.
Major Defect Variance
Meaning
Quality control plans categorize failures by their impact on product function and commercial value. A major defect variance is the measured difference between the actual number of significant flaws found in a sample and the maximum number allowed by the quality standard. It focuses on defects that prevent the product from working correctly or reduce its salability but do not pose a safety risk.
This number is the primary decider for whether a large shipment is accepted or sent back for sorting.
Statistical Range
Acceptance sampling uses mathematical tables to set the threshold for a pass or fail result. A major defect variance is calculated by comparing the results of a random inspection against the Acceptable Quality Limit (AQL) defined in the contract. If the limit is two defects and the inspector finds five, the variance is three.
This objective measurement removes the emotion from the decision to reject a supplier’s work.
Batch Assessment
Inspectors look for specific issues like non-functional buttons or significant leaks during the physical check. When the major defect variance exceeds the allowed limit, the entire lot is usually put on hold. The manufacturer then has the choice to manually sort every unit in the batch or scrap the whole run.
This process ensures that the average quality of the goods reaching the customer stays above a certain line.
Rejection Trigger
The financial impact of a high variance is immediate and often includes the cost of re-inspection. A high major defect variance indicates a breakdown in the manufacturing process that needs an immediate fix. It often leads to a formal warning to the supplier and a demand for a corrective action plan.
Repeated failures of this type can result in the termination of the sourcing agreement.