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Written By: 

Preeti Jain


Advancement in the electronics and associated segments since the invention of the first transistor in 1947 has been really phenomenal. Today, we are surrounded by electronic gadgets which have become more or less the necessities of today’s lifestyle. Computers, TVs, embedded systems, etc. can be seen everywhere. In this phenomenal growth, one thing which has been neglected is the management of the wastes generated due to electrical and electronic equipments; the waste containing substances hazardous to human life.
Symbolic Image of RoHS
Fig. 1: Symbolic Image of RoHS
E-wastes is the term used for the electronic/electrical products which have completed their useful life. Management of these e-wastes has been a cause of concern around the world. The e-wastes contain lot of constituents harmful to human health. Lead used for soldering in printed circuit boards, gaskets and glass panels can cause damage to central nervous systems, blood system and kidney. Chip resistors and semiconductor devices contain Cadmium which accumulates in kidney and liver and has toxic irreversible effects on human health. Relays and switches contain mercury which can contain chronic damage to the brain, respiratory and skin disorders. Cabling and computer housing contain plastics including PVC, the burning of which releases dioxin that can effect damage not only to immune system, but it can also interfere with regulatory hormones. Plastic housing of electronic equipments and circuit boards contain Brominated flame retardants which disrupts endocrine system functions. Hexavalent chromium used for plating cause Asthmatic bronchitis and DNA damage. Improper disposal of these wastes can allow these hazardous substances to seep into air, soil and ground water causing acute problems to human life.
With an objective to counter the ill-effects of the e-wastes, several countries pressed upon the need to address the hazardous problems and challenges caused by electronic wastes. European Union issued a directive, known as RoHS Restriction of Hazardous Substances to restrict the use of the substances in the electrical and electronic equipments. Following EU RoHS, other countries have also issued directives to handle management of the e-wastes.
Subsequent sections will present details about the RoHS


RoHS is an abbreviation of Restriction of Hazardous Substances. Often incorrectly referred by the term “Lead free”, RoHS directive is a European Union Directive 2002/95/EC. The primary objective of this directive is to put a constraint on the use of hazardous substances in electric and/or electronic equipments so as to promote better, environment friendly methods for recovery and dumping of wastes from electrical and electronic equipments. This directive puts a restriction on the utilization of 6 hazardous substances used in electrical and electronic products. RoHS directive mandates RoHS compliance of all electrical and electronic products which are meant to be sold in the EU market later than July 1, 2006, i.e., they must not contain six hazardous substances beyond the limits detailed by the directive. RoHS directive is not applicable for the spare parts for the repair or reuse of electrical and electronic equipments sold in the markets prior to 1st Jul 2006. RoHS directive is applicable in all countries of European Union.
RoHS Representational Image
Fig. 2: RoHS Representational Image
Impetus behind RoHS is the another European Directive, WEEE. WEEE is an abbreviation for Waste from Electrical and Electronic Equipment. WEEE is governed by European union Directive 2002/96/ EC which makes the treatment , recovery and recycling of EEE necessary. The prime purpose of this directive is to prevent the waste from electrical and electronic equipments and also to reduce the disposal of such wastes by re-use, recycling and other forms of recovery of electrical and electronic wastes. This directive mandates producers to assume responsibility for the recovery and recycling of their EEE products.
WEEE has been enforced according to the article 175. Each country must develop a mechanism to collect the wastes from electrical and electronic equipments as defined by the WEEE directive. All electrical and electronic products launched in the EU market later than August 13, 2006 must pass WEEE compliance and must carry the “Wheelie Bin” sticker. However, WEEE does not apply to those electrical and electronic equipments which are part of the equipments that do not fall within the scope of the directive.
RoHS and WEEE are inter-related because both the directives apply to the same type of equipments – electrical and electronics. RoHS directive restricts the use of certain hazardous substances upfront, right from the design stage while WEEE focuses on the collection, treatment, recovery and recycling of the wastes from electrical and electronic equipments.


·               Focus of the Directive
The RoHS Directive is often incorrectly referred to as the movement toward “lead-free” electronic assemblies. While Lead is one of the six substances covered by RoHS, other five included are Cadmium, Mercury, Hexavalent Chromium, Polybrominated Biphenyls(PBBs), and PBDEs. The focus of the directive is to restrict the usage of these six substances.
RoHS Overview
Fig. 3: RoHS Overview 
· Restricted Substances & their permitted levels
Article 4.1 of RoHS directive has put the restriction on the permitted levels of the six substances in the products. For the purpose of RoHS regulations, a maximum concentration value of up to 0.1% by weight in homogeneous materials for Lead, Mercury, Hexavalent Cr, PBB, PBDE and up to 0.01% by weight in homogeneous materials for Cadmium will be permitted in the manufacture of Electrical and Electronic Equipment (EEE). It is noteworthy that the presence of hazardous chemicals in packaging is also restricted.
All homogeneous (materials that cannot be disjoined by mechanical means) components within the product need to conform to the maximum concentration limits by July 1, 2006.
·               Products Covered
The Annexure IA of WEEE Directive 2002/96/ EC cover a wide range of equipment falling into ten broad product categories and with a voltage of up to 1,000 volts AC and 1,500 volts DC.
Product categories listed in Annexure 1A of WEEE directive are
1.            Large household appliances: refrigerators, , air conditioners, washers, stoves
2.             Small household appliances: vacuum cleaners, irons ,hair dryers, coffee makers,
3.            Computing & communications equipment: computers, phones, printers, copiers
4.            Consumer electronics: TVs, video cameras, DVD players, stereos
5.            Lighting & equipment: lamps, light bulbs, lighting fixtures
6.            Electrical & electronic tools: drills, saws, lathes, nail guns, sprayers, trimmers, blowers
7.            Toys and sports equipment: electric trains, videogames, treadmills
8.            Medical devices
9.            Monitoring and control instruments
10.        Automatic dispensers: vending machines, ATM machines
RoHS Directive 2002 / 95 / EC applies to electrical and electronic equipment falling under categories 1 to 7 and 10 listed in Annexure IA of the WEEE directive and to electric bulbs and luminaries in households.

RoHS Overview Cond...

·               Exceptions
Following products are exempted from RoHS compliance
1.            Industrial tools (a machine or system consisting of a combination of equipment, systems or products, each of which is manufactured and intended to be
used only in fixed industrial applications).
2.            Control and monitoring equipment
3.            National security and military equipment
4.            Medical devices
5.            Some light bulbs and some batteries
6.            Spare parts for the repair of electrical and electronic equipment (EEE) put on the market before 1 July 006 and replacement parts designed to expand the capacity of and/or upgrade EEE placed on the market before 1 July 006.
7.            The reuse of EEE placed on the market before 1 July 006.
8.            Electrical and electronic equipment which is part of another type of equipment or system (e.g. a car radio).
·               Who should comply
The directive applies to all products which are destined for sale in European markets irrespective of their place of manufacture. Any industry that is involved in selling applicable electronic products, sub-assemblies or components directly to EU countries, or an industry involved in selling applicable items to distributors or system integrators that in turn put products on the market of EU countries are affected if the products being sold contain restricted substances beyond limits.
 RoHS affects all manufacturers of electrical and electronic products; only exceptions are the ones which are exempted from RoHS compliance as mentioned in previous section. Thus, it broadly affects manufacturers of IT/telecom, consumer equipments, electrical/ electronic tools, monitoring and control instruments, equipments for toys/leisure/ sports, etc. All the manufacturers who intend to market the products in European markets must comply with RoHS.
RoHS holds the original equipment manufacturers, resellers, distributors/ importers responsible for product content. Since the prime responsibility of compliance lies with manufacturers, they must adopt methodologies for PCB fabrication, assembly, materials, and must ensure with other suppliers to contribute appropriately towards RoHS compliance of the end product.
Since RoHS compliance cannot be achieved overnight, producers need to design new products ensuring RoHS compliance and also, they may need to modify design specifications of existing products and mandate alternative production processes for the parts and subsystems used in these products. For example, printed circuit boards, power supplies, housings, drives and motors, components, connectors, switches, displays, and wiring may contain restricted substances beyond limits and, therefore, may be prohibited for sale in EU markets under RoHS.
·               Obligations
RoHS place the following requirements on the producers
·               Products put up for sale in EU markets must not contain the restricted substances above the defined limits.
·               Producers should maintain documentation of the adopted procedure to force RoHS compliance of end products. The documentation should serve to demonstrate the products compliance before they are placed in the markets.
·               Documentation must be provided to the RoHS Enforcement Authority, on request
·               Documentation should be maintained for 4 years after the production of a product placed in the market is stopped.
·               Non Compliance
Since RoHS directive prohibits the use of six substances in consumer products, the manufactures/ resellers /retailers must ensure that their products are RoHS compliant. If products are found non compliant with RoHS, legal actions are likely. Ignorance about RoHS or lack of knowledge pertaining to the presence of restricted substance in the product is certainly not the defense and cannot help the escape of the non-compliant producer. However, due diligence can.
Due diligence can act as a defense if non-compliant producer is able to demonstrate that all the actions to ensure the compliance of RoHS were taken. All the actions for RoHS compliance, preventive measures and the relevant documentation can prove in the court that he has exercised due diligence.
Image Sumbolising RoHS Environmental Appllication
Fig. 4: Evironmental Application
European Union implemented RoHS directive and put it into force on July 01, 2006. Soon after, other countries also formulated their own directive for e-waste management.
·               China RoHS
China RoHS was put into force on March 1, 2007 and is officially known as “Management Methods for Controlling Pollution Caused by Electronic Information Products Regulation”.
There are some similarities as well as differences when compared to EU RoHS
·         Many product categories that are not included in EU RoHS are included in China RoHS. Automotive electronics, medical devices, semiconductor, packaging materials, etc.
·               No exemptions are mentioned in the directive.
·           Labeling requirements are quite extensive; it must include country which is producing the product, names and list of toxic and harmful substances contained in a product, a list of packaging material ingredients, “environmentally safe period” time frame – a type of shelf-life date that establishes how long a product can be used before it leaks harmful substances.
·               Products and components imported into China will first stop at the port of entry and will be tested for compliance before entering. Products and components for re-exporting are not addressed.
·               Directive will be reviewed annually.
·               EU RoHS make only only importers, manufacturers and some retailers responsible for non-compliance; China RoHS make everyone in the supply chain responsible.
·               US RoHS
It came into force on Jan 1, 2007. Permissible limits for restricted substances are same as defined in EU RoHS.
·               Japan RoHS
Japan Directive JIS C 0950 came into force on July 1, 2006.
·               Korean RoHS
 Korea also implemented RoHS on January 1, 2008 and is also known as “The Act for Resource Recycling of Electrical/Electronic Products and Automobile”.



RoHS Testing
Fig. 5: RoHS Testing
A number of certified laboratories offer RoHS compliance testing. These laboratories test products and packaging to find out the amounts of restricted substances. They provide detailed report mentioning the exact amount (or its percentage) of each restricted substance present in the product or the packaging.
Some of the RoHS compatible test methods employed by these labs are GC-ECD, GC-MS, ICP-OES, ICP-MS, FTIR, and UV-vis. Compliance testing is also performed using portable RoHS analyzers or XRF metal analyzers which can find out the amount of restricted substances in the products. Once a product is inspected by these labs and if a product complies with the RoHS directive, a certification is granted which can then be used by the producer as a proof of the product’s RoHS compliance.
·               Lead is used for cables, solders, PCB coatings, component lead finishes. Pb-free soldering may employ options likeElectroplated tin, Electroless Nickel/Immersion Gold, Immersion Silver, Electrolytic Gold.
·               Cadmium, when used as a sacrificial coating, does not corrode easily. It is also used in rechargeable batteries ( NiCd ), plastic stabilizers, electroplating coatings, metal coating, pigments, relays, etc. However, CdO is a cancer-causing agent. For electroplating, Aluminum Ion Vapour Deposition System, Zinc-Nickel alkaline plating, Zinc-Cobalt acidic plating,Tin-Nickel acid / near neutral bath, Tin-Zinc acidic bath are the options. For contacts in relays, Ag-SnO is a likely replacement. For Batteries, NiMH and Li-Ion are the options.
·               Metallic Mercury is use in producing chlorine gas, caustic soda and in thermometers, batteries, dental fillings, relays, fluorescent lamp, sensors, etc. There are no workable alternatives for Hg-fluorescent lamp yet. Na-vapor lamps make all the objects yellow. Sulfur lamps match the sun light but are harmful because of presence of Sulphur.
·               Hexavalent Chromium ( Cr6+ ) is used for pigments, catalysis, plating and tanning. It is also used for chromate treatment of screws, nuts, etc and as surface finish by virtue of its properties of low friction coefficient, excellent corrosion resistance, high heat resistance and anti-galling properties and high hardness,. For plating, techniques like electroless plating, surface hardening, PVD, CVD , thermal spraying, organic polymer films, etc. may be used.
·               Polybrominated Biphenyls (PBBs ) and Polybrominated Diphenyl Ethers ( PBDEs ) are commonly employed as flame retardants ( FR ). It is used in TV / Display Cabinets, PCB, Wire / cable insulation and connectors. Tetra-bromobisphenol A (TBBPA),Non-halogenated flame retardants, Zinc Borate (ZnBO3), Antimony Oxide (Sb2O3) are possible alternatives
In short, no exact replacement is available. There is not yet much field data available for the new materials. In most cases, the alternative materials are costly and inferior in performance
RoHS 2
Directive 2002/95/EC on the restriction of the use of certain hazardous substances in electrical and electronic equipment (EEE) is referred to as RoHS 1 and the recast Directive 2011/65/EU is referred to as RoHS 2.
RoHS 2 entered into force on 21st July 2011 and requires Member States to transpose the provisions into their respective national laws by 2nd January 2013. The RoHS 2 Directive is part of the European Union's horizontal waste management legislation.
The problem of electronic waste management has much greater significance in India as India doesn’t have to deal with its own wastes but also dumping of e-waste particularly computer waste from the developed countries. Most of the developed countries dump their e-wastes in the developing countries.
Unlike in Europe where once a week the local municipality picks up the electronic waste, none of the global electronic brands have e-waste take back services in India. Mostly, consumers sell their e-wastes to local scrap dealers who dispose them unscientifically.
Though India has not issued any directive similar to RoHS, the Ministry of Environment and Forest (MoEF) has notified e-waste management rules for the first time in 2011. E-waste (management and handling) Rules, 2011 has put the onus of recycling and reducing e-waste in the country on the producers. The rules came into effect from May 1, 2012 


totaly nice concept.....