Restriction of Hazardous Substances Directive

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The Restriction of Hazardous Substances Directive (RoHS) 2002/95/EC was adopted in February 2003 by the European Union. The RoHS directive takes effect on July 1, 2006, but is not a law; it is simply a directive. 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 (WEEE) 2002/96/EC 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.

1 Details
2 Criticism
3 Literature
4 See also
5 External links

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Details

Each European Union member state will adopt its own enforcement and implementation policies using the directive as a guide. Therefore, there could be as many different versions of the law as there are states in the EU.

RoHS is often referred to as the "lead-free" directive, but it restricts the use of the following 6 substances:

Lead
Mercury
Cadmium
Chromium VI (Also known as hexavalent chromium)
PBB
PBDE

PBB and PBDE are flame retardants used in some plastics.

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 — for example, the sheath on a cable or the tinning on a component lead.

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 RoHS, therefore NiCd, Lead-acid and Mercury batteries are permitted despite the use of restricted substances.

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 within the EU or imported.

Certain exemptions apply:

Lead
- High melting point solders (>85% lead)
- Ceramic devices
- Certain specified alloys
- Glass used in CRTs, electronic components and fluorescent tubes.
Mercury
- Certain types of lamp

There is also legislation taking effect in China (often referred to as "China RoHS") that has similar restrictions. However, the Chinese government is being very vague about the application and responsibility for compliance. There is also some doubt as to the effective date, but it is presumed to be the same as the EU RoHS directive.

Japan does not have any direct legislation dealing with the RoHS substances, but its recycling laws have spurred the Japanese manufacturers to move to a lead-free process. These companies have also been proactive in phasing out other harmful materials which will, in effect, make their products RoHS compliant.

In addition, California has adopted similar legislation which will take effect on January 1, 2007. The California law will use the EU RoHS directive as its guide. These, as well as other legislation, effectively makes RoHS a world wide compliance issue.

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Criticism

Restricting lead content in solders for electronics requires expensive retooling of the assembly lines and different coatings for the leads of the electronic parts. The alternatives to the solders typically have higher melting points (up to 260 °C, instead of just 215 °C), requiring different materials for chip packagings and for some circuitboards; the overheating may also affect reliability of semiconductors designed for the older temperatures. The alternative solders are also harder, resulting in slow development of cracks (instead of plastic deformation, as the softer Sn-Pb solder does) because of thermal expansion and contraction as some parts heat up and cool down during operation, thus significantly impairing long-term reliability and device lifetime.Template:Citation needed Some countries therefore tend to exempt medical and telecommunication infrastructure products from the legislation. [1] There are no de minimus exemptions e.g. for micro-businesses, meaning that some cottage industries have had to close down, citing the cost of compliance.Template:Citation needed

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