XRF- A Reality Check

The Restriction of Hazardous Substances (RoHS) regulations of the European Union, and similar regulations being enacted around the world, require the virtual elimination of lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (Cr6), polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE) from electronic products. Allowable concentration levels in any homogeneous material contained within a product are extremely low: 0.01% for Cd and 0.1% for other substances by weight. The most significant issue affecting the practical validation of RoHS compliance in the day-to-day assembly environment is ensuring that no restricted substances, especially tin-lead (SnPb) materials, have inadvertently entered into the production stream....