EU RoHS Directive risk-based testing

Start with the legal target: Article 4 restrictions apply by weight in homogeneous materials, and the Directive defines a homogeneous material as material of uniform composition throughout or material that cannot be separated into different materials by mechanical actions such as unscrewing, cutting, crushing, grinding, and abrasive processes.

Article 16 gives a presumption-of-conformity route for materials, components, and EEE on which tests and measurements demonstrate Article 4 compliance, or which have been assessed in accordance with harmonised standards whose references are published in the Official Journal. That wording matters: test evidence is one route, and assessment against the cited documentation standard is another support for the conformity file.

EN IEC 63000:2018 is the harmonised standard cited for RoHS technical documentation. Commission Implementing Decision (EU) 2020/659 says the standard sets out specifications for the technical documentation required for assessing materials, components, and EEE with respect to hazardous-substance restrictions, and the IEC page describes IEC 63000 as specifying the documentation a manufacturer compiles to declare compliance.

IEC 62321 is different. Its parts describe sampling, preparation, screening, and analytical methods for particular substances or material families. Use IEC 62321 methods when testing is selected, but do not describe EN IEC 63000 as a laboratory test method or imply that IEC 62321 testing is automatically required for every part.

A practical test plan starts with the suspected material and restricted-substance group. IEC 62321-3-1 covers XRF screening for lead, mercury, cadmium, total chromium, and total bromine in uniform materials. Screening can help triage uncertainty, but it is not the same as every substance-specific determination needed for a final conclusion.

Other IEC 62321 parts in the grounding set address narrower questions: IEC 62321-5 covers cadmium, lead, and chromium in polymers and electronics and cadmium and lead in metals by AAS, AFS, ICP-OES, and ICP-MS; IEC 62321-6 covers PBB and PBDE in polymers; IEC 62321-7-1 and IEC 62321-7-2 address hexavalent chromium in corrosion-protected metal coatings and in polymers or electronics; IEC 62321-8 addresses phthalates in polymers.

The useful output is not just a lab report. Keep a decision record that explains the product identity, role, market-placement facts, homogeneous materials reviewed, supplier evidence used, testing selected or not selected, test method references, conclusions, residual uncertainty, and review trigger.

Article 7 also requires procedures to keep series production in conformity and to consider changes in product design, characteristics, harmonised standards, or technical specifications used to declare conformity. A risk-based testing decision should therefore reopen when a material, supplier, coating, plastic formulation, solder, flame-retardant system, exemption reliance, or cited standard changes.