What is BS EN 61189-5-3 - Soldering paste for printed board assemblies about?  
BS EN 61189 covers test methods for electrical materials, printed boards, and other interconnection structures and assemblies. The main objective of the EN 61189 series is to demonstrate the reliability of laminate materials and assemblies and avoid printed circuit board failures.
BS EN 61189-5-3 is an international standard for electric materials that specifies the test methods for materials and assemblies which is helpful in measuring the ionic residues which are dissolved in ionic contamination solutions.  
BS EN 61189-5-3 is a catalogue of test methods representing methodologies and procedures that can be applied to test printed board assemblies. BS EN 61189-5-3 focuses on test methods for soldering paste based on the existing EN 61189-5 and EN 61189-6. In addition, it includes test methods of soldering paste for lead-free soldering.
Who is BS EN 61189-5-3 - Soldering paste for printed board assemblies for? 
BS EN 61189-5-3 on soldering paste for printed board assemblies is relevant to:
- Manufacturers of electronic devices
- Manufacturers of printed circuits and boards
- Quality testing agencies
- Electronics industry
- Electronic engineers
- Engineers and technician
Why should you use BS EN 61189-5-3 - Soldering paste for printed board assemblies?
Solder paste is often used to connect printed circuit board pads to surface mount components like resistors and capacitors, as well as to build electrical and mechanical bindings between them. It's composed of flux paste and powdered solder.
BS EN 61189-5-3 provides users testing methods for materials or component robustness for printed board assemblies, irrespective of their method of manufacture. BS EN 61189-5-3 also provides users with a step-by-step procedure for the method, enabling users to do the method correctly.
BS EN 61189-5-3 provides users guidance on test methods for evaluating the robustness of materials or components for printed board assemblies. The methods are self-contained, with sufficient detail and description so as to achieve uniformity and reproducibility in the procedures and test methodologies.
BS EN 61189-5-3 also provides users guidance on temperature and humidity test that is implemented to ensure and verify the ability to maintain the service life if the specimen is used under constant temperature and humidity conditions.
Overall, BS EN 61189-5-3 can demonstrate the reliability and performance of a printed circuit board laminate material or a finished product and additionally, it assists users in cleaning and removing any oxides or contaminants from metal surfaces prior to soldering.
