What is RoHS?

November 1, 2005 in Latest, News Leave a reply

Originally, RoHS ("Restriction of Hazardous Substances") was the term applied only to EU RoHS.  It is now a generic term for any country’s environmental safety directive having to do (primarily) with reductions in six common hazardous materials routinely found in electronic information products.


The original EU Restriction of Hazardous Substances Directive (EU RoHS) 2002/95/EC became European Law in February 2003. This directive restricts the use of six hazardous materials in the manufacture of various types of electronic and electrical equipment.
It is closely linked with the Waste Electrical and Electronic Equipment Directive 2002/96/EC (WEEE) which sets collection, recycling and recovery targets for electrical goods and is part of a legislative initiative to solve the problem of huge amounts of toxic e-waste.

The deadline for EU RoHS compliance was July 1, 2006


RoHS restricts the use of the following six substances:
  • Lead
  • Mercury
  • Cadmium
  • Chromium VI (Also known as hexavalent chromium)
  • PBB
  • PBDE
PBB and PBDE are flame retardants used in some plastics.
Simpsons fishWhile the environmental concerns vs. the economic impact continue, these banned substances can cause very serious health problems.  Click her for detailed descriptions of the substances, where they are commonly found in manufacturing, and the associated health problems.
The maximum concentrations are 0.1% (except for Cadmium which is limited to 0.01%) by weight of homogeneous material. This means that the limits do not apply to the weight of the finished product, or even to a component, but to any single substance that could (theoretically) be separated mechanically – e.g. . the sheath on a cable, the tinning on a component lead etc).
As an example, a radio comprises a case, screws, washers, a circuit board, speakers etc. A circuit board comprises a bare PCB, ICs, resistors, switches etc. A switch comprises a case, a lever, a spring, contacts, pins etc. The contact might comprise a copper strip with a surface coating.
Everything that can be identified as a different material must meet the limit. So if it turns out that the switch’s contact coating was gold with 2300 ppm cadmium then the entire radio would fail the requirements of the directive.
Note that batteries are not included within the scope of EU RoHS, therefore Ni-Cd batteries are permitted despite the Cadmium. This is not true for China RoHS (more below)
Medical devices must be marked

The directive applies to equipment as defined by a section of the WEEE directive. These are:

  • Large household appliances
  • Small household appliances
  • IT and telecommunications equipment
  • Consumer equipment
  • Lighting equipment – including light bulbs
  • Electronic and electrical tools
  • Toys, leisure and sports equipment
  • Automatic dispensers
It does not apply to fixed industrial plant and tools. It does not apply to components and sub-assemblies – only to the finished product.
RoHS applies to these products in the EU whether made there or imported.
For EU RoHS, many exemptions apply.  This is not true for China RoHS.

China RoHS

Most EU RoHS documents do not have the information needed to evaluate or support China RoHS Marking compliance
China RoHS (formally known as "Management Methods for Controlling Pollution by Electronic Information Products") is very different from EU RoHS.
EU RoHS is effectively a "self-reporting and compliance" directive, with the possibility of retroactive enforcement.
China RoHS requires stringent marking before March 1, 2007, and China-approved testing prior to product entry into China.
On November 6, 2006, China’s Ministry of Information signed three standards into law:
  • Marking: labeling and information disclosure
  • Levels: maximum concentration value
  • Testing: testing methods
Except for the Marking standard, the final official standards have not been published but are expected soon. The official standard for the Marking phase was published in Chinese in early December of 2006.  Copyrighted English translations are available from several vendors.

EU RoHS compared to China RoHS:

  • EU RoHS compliance does not equal China RoHS compliance.
  • EU RoHS has no Marking requirements.  China RoHS Marking requirements are stringent.
  • Many components with EU RoHS certificates will still have hazardous materials which must be disclosed.
  • EU RoHS exempts many products and components from compliance.
  • China RoHS currently has no RoHS exemptions.
The need for material declaration documents is part of China RoHS, as well as several other Asian directives (Sony Green, Mitsubishi Sumitomo, and the emerging Korea RoHS standard).  These directives appeared in the second half 2006, long after EU RoHS efforts were underway.
EU RoHS requires "Certificates of Compliance", not material declaration documents for each component. 
Again, most EU RoHS documents do not have the information needed to evaluate or support China RoHS Marking compliance.

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