What Is RoHS?

RoHS stands for Restriction of use of Hazardous Substances. The acronym is pronounced “Rose”, “Roz”, “Ross” or is spelled out depending on the speaker’s preference. RoHS is a directive issued January 27, 2003 by the European Commission (EC). It directs European Union (EU) member nations to enact local legislation by August 13, 2004, which will implement the RoHS directive as regulatory requirements before the activation date of July 1, 2006.  (EU Directive 2003/11EC)

The directive is a legally binding document. It establishes regulations at the EU level, which flow to each member nation. Each member of the EU must pass its own laws, patterned after the RoHS directive, and do so by a deadline.

Substances Covered by the RoHS Directive

The RoHS directive requires that six hazardous substances be removed from all electrical and electronic equipment.  The six substances are:

  • Cadmium (Cd),
  • Hexavalent Chromium (CR VI),
  • Lead (Pb),
  • Mercury (Hg),
  • Polybrominated biphenyls (PBB),
  • Polybrominated diphenyl ethers (PBDE).

The maximum concentration of Cd is 0.01% by weight of homogeneous material, and 0.1% by weight for the other five substances. The substances may be ” present incidentally” (meaning not intentionally added) at certain levels as long as they are declared.  Some exemptions are declared in the RoHS annex, such as Hg in fluorescent lamps, Pb in certain alloys, and Pb in solder for servers (until 2010).

Lead is the hazardous substance on this list that most affects DAC’s business.  Lead is a commonly-used material in contact platings which affects not only connectors, but also switches and relays.  Lead is also the primary component of solder.  So, as board stuffers switch to higher temperature, lead-free solder, every component on the circuit board will be potentially affected (regardless of whether or not it contains lead) as each part will be subjected to much higher temperatures during the soldering process.  Many manufacturers of circuit board components that contain NO hazardous materials will have to modify/upgrade their parts anyway so that they can withstand these higher solder temperatures.