RoHS, the European Parliament directive 2002/95/EC titled Directive on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment, provides for the elimination of specific substances used in electrical and electronic equipment that are deemed to pose health and environment risks. The directive has restricted the use of six materials; lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (Cr VI), polybrominated biphenals (PBB) and polybrominated diphenylethers (PBDE). As of July 1, 2006, these materials will not be permitted in electrical and electronic equipment sold in the European Community.

Impact on the Switch Industry

Cadmium was used for years as a color pigment in plastic components. This practice began being phased out in the mid 1990's, and most switch manufacturers have completely phased out this use of cadmium. Cadmium remains the material of choice for high current electrical contacts in switches and relays in the form of Silver Cadmium Oxide (AgCdO). Silver-cad-oxide exhibits high electrical and thermal conductivity, excellent resistance to erosion and resists contact welding under arcing conditions. The high conductivity and low contact resistance is close to that of silver yet it exhibits superior erosion and welding resistance compared to silver, due to the inherent arc-quenching characteristics of cadmium oxide.  An exemption from the RoHS directive was granted for the use of cadmium and its compounds in electrical contacts on October 21st, 2005 (via an amendment to the Annex to Directive 2002/95/EC).  APEM has begun research on alternatives, but continues to offer silver-cad-oxide contacts for high current options on its industrial toggle and rocker switches.

The second material used extensively by the switch industry over the past 60 years, and the material most people relate to the RoHS directive, is lead, or more specifically tin/lead solder and tin/lead plating. Tin/lead has generally been used on all switch surface mount terminations and some through-hole terminals and mounting brackets. The RoHS directive has forced PCB and component manufacturers towards "lead free" processing, producing two challenges for the switch industry; the elimination of lead and the modification of product designs to ensure switches can withstand the higher temperatures associated with new lead-free solder processing. Switch manufacturers have been slowly eliminating tin/lead plating over the past 12 to 18 months in anticipation of the pending deadline and have been attempting to convert plastic components to higher performance alternatives.   APEM has developed alternatives to tin/lead, offering silver, gold and matte tin plating options on its switch products. APEM chose matte tin over bright tin for its reduced risk of tin whiskering.

APEM is ready - all APEM switch production lines are RoHS compliant

APEM had a few key advantages in the race towards RoHS compliance.

Vertical Integration - APEM is vertically integrated and its lean manufacturing allowed for minimum non-RoHS component inventory when the transition began. And vertical integration meant a close proximity to raw material suppliers providing for instant feedback when RoHS materials became available.

Strong European Sales - Another advantage, APEM is recognized as one of the premier switch brands in Europe. APEM sells millions of switches each year into the EU marketplace. APEM's connection to the EU forced it to begin work towards RoHS compliance in the early days, before most manufacturers contemplated the July, 2006 deadline.

High Performance Materials - APEM converted to high temperature materials over five years ago. Most power toggles and rockers are made from high-temperature thermoset plastics, capable of withstanding extreme solder temperatures. Miniature switch products, available in both through-hole and surface mount configurations were converted to high-performance thermoplastics in 2001, in anticipation of hybrid PCBs and higher solder temperatures.

Panel Mount Products - Many of APEM switch products are designed for panel mounting. These products were originally designed with gold or silver plated contacts and met the requirements of the RoHS directive from the start. Almost 80% of APEM switches have always been RoHS compliant.

Today, all of APEM's switch production lines are producing RoHS compliant products and 95% of APEM's finished goods inventory is RoHS compliant. If a customer requests a RoHS compliant switch APEM and its distribution partners can deliver it, in many cases from stock.

Impact of the RoHS Directive on the Switch Industry

Hazardous Material	Potential Effect on Switch Components	APEM Compliance with RoHS
Lead (Pb)	Tin/lead plating on terminals, mounting brackets and bushings. Note: Up to 4% lead by weight as an alloying element in copper is exempt from the directive.	Tin/lead plating phased out. New plating options: gold (Au), Silver (Ag) and matte Tin (Sn) plating. High temperature plastics are used to withstand higher temp. processing.
Cadmium (Cd)	Electrical contacts and pigments in plastics (mainly for the color red). RoHS exemption granted for use in electrical contacts.	Minimal impact. Cadmium has been removed from all plastic components. Currently used in switch contacts for high in-rush current applications.
Hexavalent Chromium (Cr VI)	Chrome plated toggles, actuators, and bushings.	No effect. Hexavalent Chromium (Cr VI) was not used in APEM chrome plated components.
Mercury (Hg)	Tilt switches, float switches - floating mercury closes electrical contact - mostly phased out.	No effect. APEM does not manufacturer tilt or level sensor switches.
Polybrominated biphenals (PBB) Polybrominated diphenylethers (PBDE)	Used as flame retardant additives in molded plastics; switch cases, covers and actuators.	No effect. PBB's and PBDE's are not used in APEM switch products.
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