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What RoHS 3 Means For PCB Assemblies

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The Restriction of Hazardous Substances (RoHS) Directive is a European Union (EU) directive that restricts the use of certain hazardous substances in electrical and electronic equipment (EEE). This includes completed assemblies, individual PCBs, cables and wires, and electronic components. The directive was first introduced in 2002 and has undergone several revisions since its introduction. The latest version is RoHS 3, introduced in 2015.

Companies looking to set up captive production operations or outsource their existing operations to friendlier shores should ensure their operations can comply with RoHS 3 directives, especially if a company wants to sell into the EU. While RoHS is most often associated with Pb-free electronics, the directive goes beyond just the elimination of lead in electronic assemblies.

What’s Required Under RoHS 3

If your company is developing a product that will be sold into the EU market, it is your responsibility to ensure your contract manufacturer and any raw materials used in the product are RoHS 3 compliant.

The primary objective of RoHS is to protect human health and the environment by minimizing the presence of hazardous substances in EEE. RoHS 3 expands on the original list of RoHS banned substances and limits to include 4 new phthalates. As of 2023, all electrical and electronic devices should be compliant with the RoHS 3 directive if the end product will be sold in the EU.

As of the 2019 implementation of RoHS 3, the current list of banned substances is as follows:

Heavy metals

  • Lead (Pb)
  • Mercury (Hg)
  • Cadmium (Cd)
  • Hexavalent chromium (Cr(VI))


  • Bis(2-ethylhexyl) phthalate (DEHP)
  • Butyl benzyl phthalate (BBP)
  • Dibutyl phthalate (DBP)
  • Diisobutyl phthalate (DIBP)


  • Polybrominated biphenyls (PBBs)
  • Polybrominated diphenyl ethers (PBDEs)

The limitations on these restricted substances is in terms of a concentration in all materials that are present in a completed product, including its mechanical elements, cables/connectors, semiconductors, packaging, and the PCB. These substances must make up no greater than 0.1% (1000 ppm) of the product in order to comply with the RoHS 3 regulation. The exception here is cadmium, which has a concentration limit of 0.01% (100 ppm).

Who’s Responsible?

Manufacturers, importers, and distributors are collectively responsible for ensuring their products comply with RoHS regulations before they can be placed into market in the EU. The regulation targets everyone along the supply chain, but it places the biggest burdens on producers of raw materials, as well as assemblers/fabricators who use raw materials to create a finished product. Raw materials producers must ensure their products intended for use in electronics assemblies do not contain restricted substances, and assemblers should ensure that they only use compliant materials if they want to ensure a final product is RoHS compliant.

Although RoHS is an EU regulation, it is influential beyond the EU. Other countries have adopted similar regulations on companies selling end-use products, as well as on manufacturers developing products to bring to market. This could include contract manufacturers who build products that must ultimately comply with RoHS regulations on behalf of clients.

Requirements for PCB Manufacturers

Companies using an EMS provider or contract PCB manufacturer should evaluate their producer to ensure they can stay compliant with RoHS 3. This means PCB manufacturers and assemblers should understand the newest regulations so that they can select the right materials suppliers. Manufacturers must ensure that their bare PCBs comply with the maximum allowed concentration values for the above list of substances.

  • Material selection: RoHS 3-compliant PCB manufacturers should select base materials that do not contain any of the above listed compounds. PCB material manufacturers have been eliminating restricted substances from standard materials (FR-4, PTFE, etc.). Alternative materials for substrates should be evaluated for compliance.
  • Supply chain management: PCB manufacturers must ensure the components and materials they source from suppliers are also RoHS compliant. This involves verifying compliance through documentation, and may sometimes require testing if non-standard materials are used.
  • Assembly process: The use of hazardous substances during PCB assembly, such as lead-based solder pastes or fluxes, must be eliminated or replaced with compliant alternatives. RoHS 3 requirements also extend to compliant adhesives, finishes, and coatings.
  • Documentation and compliance: Manufacturers are required to maintain documentation demonstrating compliance with RoHS 3. This involves keeping records of materials used during production, any test reports, and any supplier declarations. Manufacturers will use the CE marking on their PCBs to indicate compliance.

Additional Compliance Measures in REACH

The REACH directive provides additional compliance requirements that span beyond electronic components and assemblies. It is also a provision covering chemicals and substances that pose risks to human health or the environment, including carcinogens, mutagens, reproductive toxicants, persistent organic pollutants (POPs), and endocrine disruptors. REACH substances may be found in product packaging, enclosures, mechanical parts, and plastics.

Companies that want to sell into the EU should ensure their contract manufacturer and product assembler can comply with these regulations. Otherwise, there is the risk of legal liability if these regulations are overlooked. While there are no directly equivalent regulations in the United States, there are similar requirements placed on component manufacturers to ensure the same list of harmful substances does not end up in products sold on the open market.

No matter what you want to design, you can specify your RoHS 3 and REACH product compliance requirements in OrCAD from Cadence. Only Cadence offers a comprehensive set of circuit, IC, and PCB design tools for any application and any level of complexity.

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