Note:  RoHS has recently been recast. The recast broadens the regulation somewhat and removes some exemptions, but the basic structure and the regulated chemicals remain the same.

Restriction of Hazardous Substances (RoHS)

The RoHS directive (#2002/95/EC) is an attempt to reduce the environmental impact of WEEE by strictly limiting the use of lead, mercury, cadmium, Cr6+ and two brominated fire retardants in the electrical and electronic products covered by WEEE.  For details and amendments see the EUROPA website. Any product that contains more than a set amount of any of these substances in a “homogeneous material” is banned from sale in the EU after July 1, 2006.  The maximum concentration values (in homogeneous materials) are similar to those in the earlier ELV directive.

A homogeneous material is a very important (and often misunderstood) concept in RoHS – what does it mean for manufacturers?

RoHS maximum concentration values. 

Because RoHS is a single market directive it applies equally in all EU member states, unlike WEEE that allows differences in implementation from country to country.  While some exemptions from the WEEE and RoHS rules have been granted, a vast number of electrical and electronic products must comply.  Compliance with RoHS alone does not free producers from their legal obligations under the WEEE directive.

Exceptions and exemptions

Several exceptions to RoHS are set out in the directive itself.  In addition, the European Commission’s views on additional intended exceptions are explained in a list of answers to Frequently Asked Questions – although these answers are not legally binding.  Currently, it is believed that RoHS does not apply to the following:

  • Large-scale stationary industrial equipment
  • Spare parts for the repair of electrical and electronic equipment placed on the EU market before July 1, 2006, and replacement components that expand the capacity of and/or upgrade equipment placed on the market before this date
  • Reuse of electrical and electronic equipment placed on the EU market before July 1, 2006
  • Military equipment
  •  Products where electricity is not the main power source, or where the electrical or electronic components are not needed to fulfill the primary function of the equipment
  • Electrical and electronic equipment that is part of other equipment (e.g. a car radio)
  • Batteries
  • Certain specific exemptions for lead, mercury, cadmium and Cr6+.

To date, 16 specific exemptions from RoHS have been granted, while more than another 50 possible exemptions are in varying stages of review and consultation.  The exemptions that have already been approved are:

  1. Mercury in compact fluorescent lamps not exceeding 5 mg/lamp
  2. Mercury in straight fluorescent lamps for general purposes, not exceeding:
    • 10 mg in halophosphate lamps
    • 5 mg in triphosphate lamps with normal lifetime
    • 8 mg in triphosphate lamps with long lifetime
  3. Mercury in straight fluorescent lamps for special purposes
  4. Mercury in other lamps not specifically mentioned in this listing
  5. Lead in glass of CRTs, electronic components and fluorescent tubes
  6. Lead as an alloying element: in steels, up to 0.35 wt.%; in aluminum alloys, up to 0.4 wt.%; and in copper alloys, up to 4 wt.%
  7. Lead in
    • lead-based solders, containing 85 wt.% or more lead
    • solders for servers, storage and storage array systems, and network infrastructure equipment for switching, signaling, transmission, and network management for telecommunications
    • electronic ceramic parts (e.g. piezoelectric devices)
  8. Cadmium and its compounds in electrical contacts and cadmium plating, except for specific banned applications relating to restrictions on the marketing and use of certain dangerous substances and preparations (which limit the use of cadmium compounds as colorants or stabilizers in certain plastics)
  9. Cr6+ as an anti-corrosion agent in carbon steel cooling systems in absorption refrigerators (commonly used in hotel minibars, mobile homes and vehicles, or in remote areas where electricity is not available)
  10. Deca-BDE in polymeric applications
  11. Lead in lead-bronze bearing shells and bushes
  12. Lead used in compliant pin connector systems
  13. Lead as a coating material for thermal conduction module c-rings
  14. Lead and cadmium in optical and filter glass
  15. Lead in solders consisting of more than two elements for the connection between the pins and the package of microprocessors, with a lead content of 80-85 wt.%
  16. Lead in solders for completing a viable electrical connection between semiconductor die and carrier in integrated circuit flip-chip packages.

Possible Cr6+ exemptions

Among the possible RoHS exemptions currently under review is Cr6+ chromate conversion coatings used for corrosion resistance on electrical fasteners and chassis made from galvanized steel.  Exempt status is sought until July 1, 2007 to bring the electrical and electronics industry into line with the automotive industry, which has a temporary exemption from ELV requirements for Cr6+ corrosion preventive coatings on vehicles until the same date.

Another possible RoHS exemption of Cr6+ conversion coatings, for corrosion protection of electrodeposited copper foils used in circuit board laminates, is awaiting review.


Among European manufacturers the generally agreed approach to compliance with RoHS is self-declaration, without third-party testing – that is, simply putting a product on the market should be taken as a statement that the product contains less than the maximum allowed amounts of any restricted substances (in homogeneous materials).  However, this approach requires due diligence on the part of manufacturers, who must satisfy themselves that all their suppliers conform.  This can be done by obtaining materials declarations from individual suppliers, chemical analysis by the producer, or a combination of both.

Enforcement is left to individual states and may therefore vary from one country to another.  In the UK the enforcement authority is the National Weights and Measures Laboratory, which can require producers to submit technical documentation demonstrating product compliance within 28 days, and can test purchased equipment for compliance.