RoHS Requirements: Limits for Ten Categories of Hazardous Substances
RoHS certification (EU Directive 2011/65/EU on the Restriction of Hazardous Substances) for complete electrical assemblies requires that the content of ten categories of hazardous substances in the product does not exceed specified limits: lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBDE), and four types of phthalates.
Industry experts note that implementing these RoHS requirements relies on supply chain control—ensuring that suppliers of components, cables, coatings, and solder provide complete Declarations of Conformity (DoC), and that the RoHS declaration and test reports for the complete assembly support export to the EU.
The Ten RoHS Substances and Their Limits
- Lead (Pb): ≤0.1% (1000 ppm);
- Mercury (Hg): ≤0.1%;
- Cadmium (Cd): ≤0.01% (100 ppm);
- Hexavalent chromium (Cr6+): ≤0.1%;
- Polybrominated biphenyls (PBB): ≤0.1%;
Polybrominated diphenyl ethers (PBDE): ≤0.1%; - Four phthalates (DEHP/BBP/DBP/DIBP): ≤0.1% each.
Key Points for RoHS Compliance
First, supply chain control.
Suppliers of components and materials must provide RoHS compliance documentation (DoC/test reports) to ensure compliance at the source.
Second, material substitution.
Manufacturing processes—such as coatings (hexavalent chromium passivation) and solder (lead-tin solder)—must be modified to meet RoHS standards.
Third, declaration for the complete assembly.
Sign the Declaration of Conformity (DoC) and archive the technical documentation.
Fourth, conduct testing and verification: submit high-risk materials for testing (XRF screening followed by chemical analysis) and keep reports on file for future reference.
Pitfalls to Avoid
First, “loss of supply chain control”: component suppliers lack RoHS documentation, casting doubt on the compliance of the finished product.
Second, “misuse of exemptions”: penalties resulting from the incorrect application of exemption clauses (e.g., regarding certain lead-based solders).
Third, “missing documentation”: incomplete DoCs or technical files leading to product delisting during EU spot checks.
Trends and Recommendations
RoHS requirements are becoming increasingly stringent (with an expanding list of regulated substances), while supply chain digitalization (via compliance data platforms) is enhancing control efficiency.
Exporters are advised to ensure compliance at the supply chain source, implement effective material substitutions, and maintain comprehensive documentation.
RoHS serves as a “green threshold”: ensuring substance compliance is the key to accessing the European market.
