What is BS EN 62435-2 - Long-term storage of electronic semiconductor devices about?  
BS EN 62435 is a European Standard that discusses electronic components. The IEC 62435 series is intended to ensure that adequate reliability is achieved for devices in user applications after long-term storage.
BS EN 62435-2 is the second part of the multi-series that applies to the long-term storage of electronic components.
BS EN 62435-2 is related to deterioration mechanisms and is concerned with the way that components degrade over time depending on the storage conditions applied. This part also includes guidance on test methods that may be used to assess generic deterioration mechanisms. Typically, this part is used in conjunction with IEC 62435-1 for any device long-term storage whose duration may be more than 12 months for a product scheduled for long-duration storage. Mechanisms that apply to specific component types are detailed in IEC 62435-5 to IEC 62435-9 (proposed)1.
Who is BS EN 62435-2 - Long-term storage of electronic semiconductor devices for? 
BS EN 62435-2 on long-term storage of electronic semiconductor devices is useful for: 
- Manufacturers of electronic semiconductor devices
- Authorities involved with storage, handling, and inspection of electronic semiconductor devices
- Manufacturers of electronic equipment and components
- Aerospace and automobile industry
- Companies involved in R&D of semiconductor technology
- Product design engineers
- Electronic engineers
Why should you use BS EN 62435-2 - Long-term storage of electronic semiconductor devices?  
Long-term storage is defined as planned storage of components to extend the life-cycle for a duration with the intention of supporting future use. All failures affecting electronic components initiate originally from a mechanism of a mechanical, chemical, electrical type, or a combination of the three types.
BS EN 62435-2 is a document for long-term storage of electronic devices drawing on the best long-term storage practices currently known.
BS EN 62435-2 is intended to give practical guide to methods of long-duration storage of electronic components where this is intentional or planned storage of product for a number of years.
Since it is important to estimate the impact of the constraints on the failure mechanisms in order to determine any possible induced acceleration, BS EN 62435-2 recommends the main test methods, the nature of the defects, the relative cost and their efficiency, as well as the test conditions and average times.
The purpose of the technical validation of the components with a view to their storage, in compliance with BS EN 62435-2, is to detect the batches which do not offer proper reliability and life-time guarantees.
BS EN 62435-2 can assist you in storing electronic devices for long periods of time, in order to maintain as-received solderability and avoid any degrading impacts to the part over time. Degradation concerns such as moisture, electrostatic fields, ultraviolet light, large temperature changes, airborne pollutants, and outgassing can thus be avoided.
