The 5 Most Common Quality Problems in Chinese Manufacturing and How to Prevent Them
AQL (Acceptable Quality Level) is a statistical sampling method. For most consumer goods, AQL 2.5 for major defects and 4.0 for minor defects is standard. Critical defects always require zero tolerance. The sampling size is determined by ISO 2859 or ANSI/ASQ Z1.4 tables. A batch of 3,000 units requires 125 samples. If more than 7 major defects are found, the entire batch fails and requires 100% inspection. Always specify AQL levels in your purchase contract.
Pre-Production Inspection (PPI) is the most cost-effective quality step. It happens when 10-15% of production is complete. At this point, any issues can be corrected before they affect the entire batch. PPI typically checks: first article dimensions against spec, material verification, color/ finish approval, packaging design confirmation, and production line setup. The cost is typically $300-400 and prevents thousands in potential rework.