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Evaluation of the Danish Statutory Order on Lead 6 Other uses of lead as a metal
The list of other uses of lead as a metal is extremely long and, with only few exceptions, no significant progress has been made in finding substitutes to lead, except in areas subject to international regulation. The most important international regulation in this connection is EU Directive 2002/95/EC (the RoHS Directive) and EU Directive 2000/537EC on End-of-Life Vehicles. The RoHS Directive restricts the use of lead etc. in electrical and electronic equipment, while the EU Directive on end-of-Life Vehicles only limits the use of lead etc. in vehicles. See Annex 2. Table 6.1 presents an overview of the relevant uses of lead. Where necessary, this overview is described in more detail below. With regard to the use of lead as a metal, the Lead Order does not introduce a general ban, but only a ban on selected uses. Therefore, the following focuses on whether alternatives have been developed enough to make a ban possible. On the other hand, recommendations have not generally been given. 6.1 Soldering alloys for electronicsIn recent years there have been considerable developments in alloys for soldering electronics, both in Denmark and abroad. Developments have been accelerated in particular by the RoHS Directive. There are acceptable alternatives for most purposes, but there remains a need to adapt the manufacturing processes to the new soldering materials [DTI 2003]. The alternative soldering alloys on the market include SnAgCu (tin-silver-copper), which currently seems to be the most popular substitute. In addition SnCu (tin-copper), SnAgBi (tin-silver-bismuth), SnZn (tin-zinc), SnAg (tin-silver) and SnAgIn (tin-silver-indium) [NoNE 2004] are also being tested and used. The choice of substitute depends on both price and technical properties, and it varies according to the method of soldering - "reflow" soldering versus "wave" soldering or manual fitting [Elfnet 2005]. Today there are no acceptable alternatives for solder with a high melting point (i.e. tin-lead soldering alloys with more than 85 % lead), and this use has been exempted from the ban in the RoHS Directive (cf. Annex 2). Sn-80Au (tin-80gold) could be a practical alternative, but it is very expensive [JBCE 2004]. Other uses of solder containing lead currently exempt from the ban in the RoHS Directive include (cf. Annex 2): Lead in solders for servers, storage and storage array systems, network infrastructure equipment for switching, signalling, transmission as well as network management for telecommunications.
Table 6.1 Other uses of lead as a metal
Evaluation With regard to lead solder in electronic and electrical equipment which is not covered by the RoHS Directive, it seems that only limited immediate drip-down effects from the RoHS Directive can be expected. The fact that lead solder is both cheap and well-tested means that many and perhaps the majority of manufacturers will continue using this type of solder. Although in practice it would clearly be possible to substitute with unleaded solder for many purposes, it is unlikely that manufacturers of the relevant equipment are ready to do so. Furthermore, it is not known how willing manufacturers are to adapt their products to the Danish market. This means that a ban on lead in soldering alloys for all types of electronic and electrical equipment could cause difficulties for imports of important equipment to Denmark. 6.2 Low-melting alloysAlloys which melt at a relatively low temperature are used for protection against fire and overheating in electronic equipment. Alloys based on lead and cadmium dominate the market. Alternatives are InSn (indium-tin) or BiSn (bismuth-tin) alloys, but indium is very expensive. Fuses to protect against overheating in electronic equipment can be made redundant by better cooling [Goodman and Stuckwick 2002]. At the moment, the RoHS Directive has introduced a ban on the use of lead for this purpose in electronic equipment (cf. Annex 2). According to [Goodman and Stuckwick 2002] it is unlikely that the existing alternatives are practical for all purposes. Evaluation 6.3 Other alloysLead is used as an alloying element in small concentrations in several metals to improve their manageability, e.g. machining the material. Lead is used for this purpose in steel, aluminium, and copper alloys. According to [Petersen 2005] ordinary recycled steel (also known as "black steel") contains large amounts of lead as an impurity. In order to examine the possibilities of reducing lead impacts on employees, a committee for health and safety in the casting and foundry sector completed an assessment of possible substitutes for lead. The group of experts behind the report deem that the following five alloys are less harmful to health than traditional bronze containing lead [Tiedje et al, 2003]:
In summary it seems that there are substitution possibilities for the most important product uses. The alternatives are typically more expensive, but they have the advantage of fewer environmental and health and safety problems [Tiedje et al, 2003] However, it should be noted that both the RoHS Directive and the Directive on End-of-Life Vehicles allow for exemptions for lead as an alloying element in steel containing up to 0.35 % lead by weight, aluminium containing up to 0.4 % lead by weight and as copper alloy containing up to 4 % lead by weight. (cf. Annex 2). For aluminium in vehicles it is also permitted to have up to 1.5 % lead by weight up to 1 July 2008. Furthermore there are exemptions for lead in lead/bronze bearing bushes and bearing liners (cf. Annex 2). Evaluation It is worth considering the possibilities to promote the use of lead-free alloys in Danish industry. 6.4 BalancingLead is used to balance wheels on vehicles and in numerous other applications such as ventilators, wind turbine wings, machine components and pianos. Wheel weights Today, lead weights are completely banned in the EU on cars with seats for up to 8 passengers and vans with a total weight of up to 3.75 tonnes (cf. EU Directive on End-of-Life Vehicles [EU 2005a]). In connection with the introduction of this Directive, the need to use lead to balance wheels on vehicles was assessed. Today, wheel weights are covered by the ban on lead. According to [Buergel 2004] alternative materials (zinc, tin, steel etc.) have been used on vehicles with type approval after 1 July 2003. According to an important manufacturer of wheel weights, today alternatives are supplied made of zinc, steel, tin and copper. Which substitute is best is determined from case to case. Wheel weights made of lead are still available for vehicles of more than 3.75 tonnes, which are not covered by the EU Directive [Trax 2005]. The existing ban in Denmark against using lead as a wheel weight applies to vehicles with type approval after 1 July 2003 as well as spare parts for these vehicles. According to [Grau 2006], this means that it is illegal to fit lead weights when changing tyres on cars placed on the market after 1 July 2003. Moreover the EU Directive was later amended so that today it is also illegal to use lead in wheel weights on vehicles approved before July 2003. This amendment is expected to be implemented in Danish legislation during 2006 [Grau 2006]. There is nothing to prevent fitting wheels with lead weights when changing tyres in Denmark. As it is considerably easier and cheaper for Danish workshops to use lead weights, it is probable that today Danish cars are extensively fitted with lead weights following a tyre change. The vehicles not covered by EU Directive 2000/53/EC on End-of-Life Vehicles are primarily vehicles with a total weight of more than 3.75 tonnes. In principle there is no great technical difference between balancing wheels on vehicles of more than 3.75 tonnes and balancing wheels on lighter vehicles such as cars. The most important difference is that the wheels are typically larger and that for harder substitutes it is necessary to manufacture weights which fit the individual types of rim. In connection with this project, information has not been obtained from Danish importers of vehicles weighing more than 3.75 tonnes on whether it is practicable for importers to initiate substitution of wheel weights on imported vehicles. Pianos No pianos are manufactured in Denmark, and about 80 % of Danish pianos are manufactured in Germany. Production has followed the same principles for the past 400 years, including using lead to balance the keys. Lead is still used to balance the keys [Danielsen 2005]. Most Danish pianos are repaired in Denmark. Many of these repairs involve balancing the keys with lead, in the same way as when the piano was made. This lead is imported by wholesalers and sold on Danish piano repairers. An important Danish wholesaler would like to use something other than lead, but the long tradition for using lead means there is general reluctance to avoid lead [Danielsen 2005]. Other uses No information has been obtained on developments in the use of lead for balancing in other contexts. It is known that in addition to balancing wheels, lead is also used extensively to balance wind turbine wings and ventilators. It is also used to balance machine components such as flywheels, clutches, drive shafts, electric rotors, fans, pulleys, rollers etc. [Lassen et al 2003]. It is known that in practice wind turbine wings and ventilators are balanced with lead and with other materials such as cast iron, polyurethane etc. [Lassen et al 2003]. No information has been obtained on the technical arguments for choosing specific materials in specific situations. It is likely that lead remains the preferred material for balancing many machine components. Arguments for using lead are based on cost (lead is cheap), that lead is easy to work with (lead can be soldered on and ground into shape), weight and tradition. The weight of lead can be very important in situations where balancing is to be carried out in places with restricted space. Otherwise there are no other properties which give rise to technical barriers to substituting lead. In many cases, tin will have comparable properties, except that tin is more expensive and not quite as heavy as lead. Evaluation In principle, it is also possible to do without lead to balance wheels on vehicles of more than 3.75 tonnes. Therefore, practical possibilities should be examined to substitute lead in wheel weights for vehicles of more than 3.75 tonnes imported into Denmark. In addition, balancing wind turbine wings is significant in terms of amount. It seems that it is possible to substitute the use of lead to balance wind turbine wings. Therefore stopping or restricting the use of lead for this purpose should be examined. With regard to other uses, it is deemed that in many situations lead could be replaced by other materials. Quantities of lead consumed for these purposes are of limited importance, however. 6.5 Protection against radiationHistorically, because of its high density, lead has been used as protection against radiation, including X-rays, and, as far as we know, the use of lead for this purpose has not undergone dramatic change [Lauritsen 2005]. It is possible to protect from X-rays using other materials than lead. These must be heavy materials (high atomic number). Concrete is a possibility, but it is impractical where flexibility is required, for example in aprons etc. [Lauritsen 2005]. Metallic lead powder is still used in production of rubber aprons to protect against X-rays [Thisgård 2005]. Evaluation 6.6 Sound and vibration suppressionThe use of lead to suppress vibration in vehicles is still permitted according to the EU Directive on End-of-Life Vehicles (cf. Annex 2). According to [Buergel 2005] steel is often used in cars, but in some circumstances lack of space means that lead is the only practicable solution. There have been no attempts to obtain further information about the use of lead for noise and vibration suppression. According to the mass-flow analysis of 2000, the consumption of lead for this purpose by industry can be regarded as marginal [Lassen et al 2003]. Evaluation It is likely that it will be possible to substitute lead with other materials in many circumstances. However, there may be uses where it would be very difficult to find alternatives. Marginal consumption means that there would only be a minimal effect from efforts in this area. 6.7 Mantles for cablesAccording to NKT [Thiesen 2005], today lead has been substituted in all new cables > 24 kV, laid underground. Lead has been replaced with aluminium combined with the use of more copper. This compensates for the earlier problems with eddy currents in the aluminium foil and the resistance associated with these. Repairs to existing lead-mantled underground cables still require the use of small quantities of metallic lead. Lead is still used in underwater cables, but this is also being substituted. Evaluation 6.8 AmmunitionToday, use of lead shot is banned in Denmark, both for hunting and for sports shooting, except in selected sports shooting facilities. On the other hand, the use of lead slugs for hunting and sports shooting is unrestricted. The status of lead-free ammunition is described in [Hansen et al 2004], and this report forms the basis of the following. Internationally there is currently great development in lead-free ammunition. The most important driving forces behind this development include:
Today, a Nordic ammunition firm supplies the Swedish, Norwegian and Finnish armed forces with lead-free ammunition, and in 2004 an agreement on production under licence was made between this firm and the Danish Ammunitionsarsenalet. The lead-free ammunition meets NATO requirements and costs about 20 % more than lead ammunition. There is no information on what materials have substituted the lead. A possible substitute may be tungsten alloys. New information indicates that there are possibly undesirable environment and health effects from tungsten [Hansen et al 2004]. All calibres of lead-free ammunition for hunting are also available on the market. These are usually copper slugs, see [Lapua 2006]. However, hunters are not happy with the ban on lead-containing ammunition [Hunters Magazine 2004]. Whether there are alternatives for all ordinary weapons for hunting or sports shooting has not as yet been investigated. As copper is lighter than lead, the cartridges will usually be longer and it is possible that these cartridges will not suit all rifles. There are also problems with rifles which do not use a standard calibre. As far as is known, lead-containing ammunition is by far the most popular for sports shooting. It is known that the International Sports Shooting Association is working to organise environmentally friendly ranges rather than to substitute lead. It is unclear whether building environmentally friendly ranges is cheaper or more expensive in the long term than substituting lead [Hansen et al 2004]. Evaluation It is probably also possible to substitute lead in sports shooting. Just as for hunting there will be a number of practical problems related to a ban, and these will have to be solved in cooperation with the relevant users and their organisations. 6.9 Other usesNew developments have not been examined for a number of the other uses listed in Table 6.1. In practice this will probably not be the case. Alternatives are available on the market for most of these uses. These alternatives will usually contain other metals or other materials. It is deemed unlikely that further substitution will take place for these uses without influencing the market, for example through restrictions on the use of lead.
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