The Restriction of Hazardous Substances Directive, commonly called RoHS, is a directive on the use of certain elements in electrical and electronic devices. The definition and aim of the RoHS directive is quite simple: it aims to restrict certain dangerous substances commonly used in electrical and electronic equipments. Any RoHS compliant component is tested for the presence of Lead (Pb), Cadmium (Cd), Mercury (Hg), Hexavalent chromium (Hex-Cr), Polybrominated biphenyls (PBB), and Polybrominated diphenyl ethers (PBDE). It is closely linked with the Waste Electrical and Electronic Equipment Directive (WEEE). .

    RoHS does not require any specific product labelling, however many manufacturers have adopted their own compliance marks to reduce confusion.