RoHS, stands for the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment, that is, "Electrical and Electronic Equipment restrict the use of certain hazardous substances directive." RoHS instructions to July 1, 2006 after the EU market of electrical and electronic products contain lead Pb, Hg Hg, Cd Cd, hexavalent chromium Cr (VI), polybrominated biphenyls PBBs, polybrominated diphenyl ethers PBDEs and other six hazardous substances shall not exceeded, to control electrical and electronic equipment in the six major content of harmful substances. Cadmium content of which the maximum allowable value is 100ppm (0.01%), the maximum allowable value of the other five levels are l000ppm (0.1%).

On 1 July, 2011, EU published the recast vesion of RoHS 2011/65/EU (RoHs 2.0) to expand products scope, under which scope has become 11 catogories. Hazardous substances restricted are still those 6 kinds of substances under 2002/95/EC, but 4 "Priority Concern" substances (HBCDD、DEHP、DBP、BBP) are proposed for further restriction. Additionally, CE marking is required under RoHS 2.0, as well as markert surveillance.

In the light of RoHS 2.0, contents of 6 kinds of hazardous substances in 10 category products shall not exceed limits specified under this directive as the following table, or not they can not be put on the market of EU.