Several issues should be considered for soldering in terms of QA.
Workmanship: shall be a level of quality adequate to assure that processed products meet the performance requirements of the engineering documentation.Inspection: Inspection for acceptability shall be performed on all solder connections, parts mounting and condition, conductor routing, and PWB features to requirements. Requirements may be individually set depending on the system and its intended application. At a minimum all soldered connections will be visually inspected.
QA shall verify all workmanship, test, inspections, cleanliness, environments, and measurements. QA shall also ensure that tools and equipment be verified for conformance to the applicable requirements. All materials shall conform to ANSI/J-STD-004 and 06.
Denatured Ethyl Alcohol
Butyl Alcohol, Secondary
27 CFR 21.35 Code of Federal Regulations, Title 27, Alcohol, Tobacco, and Firearms, Part 21, Formulas for Denatured Alcohol and, Rum, Subpart D, Specially Denatured Spirits Formulas and Authorized Uses, Formula No. 3-A
O-M-232, Grade A
Detergent cleaners and saponifiers
1 megohm-cm, minimum resistivity
Solderability of materials shall be verified for compliance.
Cleanliness: Cleanliness testing is used to monitor the effectiveness of post soldering PWA cleaning processes. Two basic test methods are recommended: resistivity of solvent extract test, and sodium chloride (NaCl) equivalent ionic contamination test. See NASA-STD 8739.3 for additional specification.