Russ: In December 2003, the European Commission released the following statement: �The commission services have prepared a draft Commission decision establishing maximum concentration values pursuant to Article5(1)(a) of Directive 2002/95/EC. The proposed values have been discussed at the Technical Adaptation Committee (TAC) meetings this year.�
The values they refer to are the 0.1% for lead, mercury, hexavalent chromium, PBB and PBDE and 0.01% for cadmium.
The most significant bromine sources of a printed circuit board are flame retardants and resins, both based on bromine, for example tetra-bromo-bisphenol A [TBBA].
At the present time, typical bromine contents of current FR4 base material types lie between 18 and 21% by weight of bromine. But also in some solder resists bromine-based components are formulated in order to meet the requirements of the non-flammability test according to UL 94 V-0.
Incineration of some brominated flame retardant produces toxins: * polybrominated biphenyl ether (PBBE) * polybrominated biphenyl oxide (PBBO)
Polybrominated diphenyl ether (PBDE) [Three most common commercial products are penta-BDE, octa-BDE and deca-BDE.] PBDEs have been used extensively over the past two decades as flame retardants in plastics, textiles, coatings and electrical components found in many common products including televisions, computers, and electrical appliances.