WEEE: Waste Electrical and Electronic Equipment
Directive 2002/96/EC covers the waste management of electrical and electronic products & requires that new equipment placed on the market within Europe must comply with the directive
RoHS: Restriction of the use of certain Hazardous Substances in electrical and electronic equipment
Directive 2002/95/EC bans the use of certain restricted substances in end products to prevent them from entering waste streams. The directive sets maximum allowable limits of the hazardous substances Pb, Cd, Hg, Cr (VI) and Br (from brominated flame retardants: PBB & PBDE).
ELV: End of Life Vehicles
Prohibits the use of these hazardous substances in vehicles sold after July 2003.
Measurement Methods of Hazardous Substances
Hazardous substances which are subject to the application of WEEE/RoHS and ELV directives are shown below with the representative measurement methods. Of these substances, both lead (Pb) and cadmium (Cd) have been widely applied as stabilizers for plastic materials. In addition, the former has found application as an agent intended to improve the softness, machinability or any other functional property of plastics, while the latter has been used as a coloring agent. If any plastic material containing highly concentrated Pb and Cd is included in any part/component which is being treated for recycling, all of the other materials constituting such part/component will be rendered unusable. It is of particular important, for this reason, to analyze all plastic materials for inclusion of these two elements. In order to analyze Cd and Pb, inductively coupled plasma (ICP) and other forms of atomic emission spectroscopy (AES) have been the common choice.
Maximum Allowable Limits of Hazardous Substances
Element |
Maximum expected limit |
Pb |
1000 ppm1 |
Hg |
1000 ppm |
Cd |
100 ppm |
Cr |
1000 ppm |
PBB |
1000 ppm2 |
PBDE |
1000 ppm2 |
1 For ELV, limit for Pb in Steel and Aluminum
is 4000 ppm
2 Regulation of PBB and PBDE only for RoHS
Typical Flowchart of WEEE/RoHS Analysis
NG: Not
good, must return to supplier
?: Concentration borderline, analyze by ICP
OK: WEEE/RoHS compliant, on to
production
Under the directives, samples can first be screened with XRF. If the samples pass the limits, they are okay to continue into production and assembly. If they are above the limits, they must be returned to the supplier. If the results are borderline or below the detection capability of XRF, then ICP must be used for the analysis.
Categories of Products Covered by RoHS