RoHS (Restriction of Hazardous Substances) and REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) form the bedrock of European environmental compliance for electronics engineering. While functionally distinct, both directives share a common goal: protecting human health and the environment by strictly regulating the use of toxic chemicals in hardware manufacturing.
Complying with these directives is not a testing exercise; it is exclusively a supply chain and BOM (Bill of Materials) management discipline.
RoHS: Directive 2011/65/EU
The RoHS directive restricts the use of specific hazardous materials in the manufacture of various types of electrical and electronic equipment. Unlike some directives, RoHS compliance is geographically expanding; versions of RoHS now exist in China, California, Taiwan, and Korea, making it a globally required engineering baseline.
The Restricted Substances
As of the RoHS 3 amendment (Directive 2015/863), there are ten restricted substances. The maximum permitted concentrations in non-exempt products are typically 0.1% or 1000 ppm (except for Cadmium, restricted to 0.01% or 100 ppm) by weight of a homogeneous material:
- Lead (Pb): The most historically significant restriction, driving the global transition from SnPb (Tin-Lead) to SnAgCu (Tin-Silver-Copper, or “SAC”) lead-free solder profiles in SMT manufacturing.
- Mercury (Hg)
- Cadmium (Cd)
- Hexavalent chromium (Cr6+)
- Polybrominated biphenyls (PBB) (Flame retardants)
- Polybrominated diphenyl ether (PBDE) (Flame retardants)
- Bis(2-ethylhexyl) phthalate (DEHP) (Plasticizer)
- Butyl benzyl phthalate (BBP) (Plasticizer)
- Dibutyl phthalate (DBP) (Plasticizer)
- Diisobutyl phthalate (DIBP) (Plasticizer)
Engineering Implications of RoHS
Homogeneous Material Rule:The 0.1% limit does not apply to the whole PCB assembly. It applies to every mechanically disjointable substance. For example, the plastic housing of an IC, the plating on its pins, and the die attach adhesive within the IC are all evaluated individually.Reflow Profiles:Lead-free (RoHS) solders require higher reflow temperatures (e.g., peak ~245°C–260°C) compared to legacy tin-lead solder (~215°C). The thermal design of the PCB and the moisture sensitivity level (MSL) of all components must be strictly managed to prevent popcorning or delamination during assembly.Exemptions:Certain high-reliability sectors (aerospace, defense, some medical implants) may invoke specific Annex exemptions permitting leaded solder to prevent issues like tin whiskers (conductive crystalline structures that grow on pure tin surfaces and cause short circuits).
REACH: Regulation (EC) No 1907/2006
While RoHS is specific to electronics and targets ten compounds, REACH applies to all products (including clothing, furniture, and chemicals themselves) and manages thousands of substances. It places the burden of proof on companies to demonstrate that the substances they use are safe.
Key REACH Concepts for Hardware
For electronics manufacturers, REACH compliance centers entirely around Articles (objects given a special shape, surface, or design, like a PCB assembly) and SVHCs (Substances of Very High Concern).
- SVHC Candidate List: The European Chemicals Agency (ECHA) maintains a constantly growing list of SVHCs (carcinogens, mutagens, reproductive toxins). This list is updated every six months (unlike RoHS, which is static).
- The 0.1% Threshold: If any component within your product contains an SVHC in a concentration above 0.1% weight by weight (w/w), you have legal obligations.
- SCIP Database: If SVHCs are present >0.1%, manufacturers or importers must register the product in the EU’s SCIP (Substances of Concern In articles as such or in complex objects (Products)) database. This ensures waste operators have data for end-of-life recycling.
The Inovasense Approach to Environmental Compliance
RoHS and REACH compliance cannot be proven with an oscilloscope; it is proven with data.
At Inovasense, environmental compliance is automated directly into our BOM generation process. We utilize Altium 365 and real-time supply chain API integrations (SilicionExpert, Octopart) to continuously query the component manufacturer’s material declarations (Full Material Disclosures or IPC-1752A forms).
If a selected microcontroller or passive component goes obsolete or its REACH SVHC status changes due to a bi-annual ECHA update, our automated BOM risk checks flag the violation before the product moves to procurement. This ensures our clients’ Technical Files remain legally bulletproof throughout the product’s entire lifecycle.