Do I need to get my products tested for RoHS compliance?
If you are an assembler of OEM or CEM PCBs, a European manufacturer selling within the EU, or an importer of manufactured product into the EU, you must be able to demonstrate compliance with the Restriction of Hazardous Substances (RoHS) Directive (2002/95/EC) when your finished product is put on the market in the EU.
Which substances are restricted?
Electronic and electrical equipment must not contain more than the maximum permitted levels of lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs).
What is the deadline for compliance?
- The requirements of the RoHS Directive come into force on 1st July 2006. Products put on the market after this date will be required to be compliant.
- RoHS does not apply to any products that are already "on the market" (already in the supply chain) in the EU prior to this date; they can continue to be sold.
- WEEE: By 13 August 2005, products "put on the market" after this date should be marked with the crossed-out wheelie bin to identify these products cannot be processed with the regular refuse.
What are the implications if my product doesn't comply by then?
An enforcement authority may ask to see evidence that a producer has used due diligence and taken reasonable steps to comply with the requirements of the RoHS Directive. Failure to comply could result in the eventual withdrawal of your product from the market.
How can I find out whether my product complies?
If materials declarations or certificates of compliance for each component of your product are not available from your suppliers, or if you have any doubts over the accuracy or completeness of that information, it is advisable to subject your product to a screening test, which measures the concentration of the restricted substances within it.
Does the same apply to packaging materials?
- EU's 94/62/EEC Directive requires the content of lead, cadmium, mercury, hexavalent chromium cannot exceed 100ppm.
- For glass and ceramic packaging material, cadmium content cannot exceed 1 ppm, hexavalent chromium and mercury cannot exceed 5ppm.
What problems are there for using Lead-free solder?
- Higher melting point of Lead-free solder may cause physical and thermal damage to components and PCB.
- Lead-free solder has poor wetting ability and therefore needs a more active (corrosive)
- flux to improve wetting.
- Lead-free solder joints need longer time to solidify.
- The solder point will appear dull in color.
- The high tin content of Lead-free solder will shorten life time of the soldering tips.
How to cope with the above problems?
- Do not try to increase the temperature of the soldering tip to accommodate for higher melting point, because this will cause more damage to components and PCB.
- Also, higher temperature will only make soldering of Lead-free solder even more difficult because more oxidation will form causing even worse wetting.
- Keep using the same temperature as normal with tin/lead solder.
- Instead, choose the largest soldering tip possible for the joint, and use a high power soldering iron.
- This way, the larger tip (with larger volume mass) has better heat retention and the fast thermal recovery of the tip will help smooth out the Lead-free soldering process.
Why does Lead-free solder shorten life time of soldering tips?
- Tin itself is a very active metal.
- Tin reacts with the iron (Fe) layer of soldering tips and the iron layer is eroded away.
- The higher the temperature, the faster the erosion speed.
- With almost all Lead-free solder, the percentage of tin is over 90%.
- Since there is higher tin content, with higher temperature and presence of more active flux, the erosion of soldering tips occurs faster than regular tin/lead solder.
How should we care for the soldering tip to extend the life?
- Keep the tip the cleanest possible during use.
- Always TIN the tip before putting the soldering iron back in the holder.
- If you are not using the soldering iron for a while, e.g. over 10 minutes, turn off the soldering iron.
- Use the lowest possible soldering temperature.