This part of IEC 61193 defines methods of registration and analysis of defects on soldered printed board assemblies. Methods are described to allow effective comparison of performance between products, processes and production locations and can serve as a basis for general quality improvement. The standard specifies defect data collection in two categories. Category 1 ppm data: this category provides data for registration purposes intended to enable overall performance comparison of assembly operations. Category 2 ppm data: this category provides data intended for individual subprocess assessment, analysis and control purposes.