Blades, K., Allenby, B. “Environmental Effects” The Electrical Engineering Handbook Ed. Richard C. Dorf Boca Raton: CRC Press LLC, 2000 111 Environmental Effects 111.1 Introduction 111.2 Industrial Ecology 111.3 Design for Environment 111.4 Environmental Implications for the Electronics Industry 111.5 Emerging Technology Integrated Circuits?Printed Wiring Boards 111.6 Tools and Strategies for Environmental Design Design Tools?Design Strategies?Conclusion? Acknowledgements?Disclaimer 111.1 Introduction The importance of electronics technology for consumers, and the electronics sector for the global economy, is already substantial and continues to grow rapidly. Such growth and innovation coupled with the global concerns for the environment and the need to better manage the resources of the earth pose many challenges for the electronics industry. While thought of as a “clean” industry, the technological advances made by the industry creates a significant demand on the earth’s resources. As an example, the amount of water required in the production of semiconductors, the engines that motor most of today’s electronic gadgets, is enormous—about 2000 gallons to process a single silicon wafer. Building silicon chips requires the use of highly toxic materials, albeit in relatively low volumes. Similarly, printed wiring boards present in most electronic products and produced in high volume use large amounts of solvents or gases which are either health hazards, ozone depleting, or contribute to the greenhouse effect and contain lead solder. The challenge for the industry is to continue the innovation that delivers the products and services that people want yet find creative solutions to minimize the environmental impact, enhance competitiveness, and address regulatory issues without impacting quality, productivity, or cost; in other words, to become an industry that is more “eco-efficient”. Eco-efficiency is reached by the delivery of competitively priced goods and services that satisfy human needs and support a high quality of life, while progressively reducing ecological impacts and resource intensity, to a level at least in line with the earth’s estimated carrying capacity. Like sustainable development, a concept popularized by the Brundtland Report, Our Common Future, the notion of eco-efficiency requires a fundamental shift in the way environment is considered in industrial activity. Sustainable development—“development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [World Commission on Environment and Development, 1987]—contemplates the integration of environmental, economic, and technological considerations to achieve continued human and economic development within the biological and physical constraints of the planet. Both eco-efficiency and sustainable development provide a useful direction, yet they prove difficult to operationalize and cannot guide technology development. Thus, the theoretical foundations for integrating technology and environment throughout the global economy are being provided by a new, multidisciplinary field known as “industrial ecology”. Karen Blades and Braden Allenby Lawrence Livermore National Laboratory ? 2000 by CRC Press LLC The ideas of industrial ecology, which have begun to take root in the engineering community, have helped to established a framework within which the industry can move toward realizing sustainable development. The electrical, electronics, and telecommunications sectors are enablers of sustainability because they allow the provision of increasing quality-of-life using less material and energy, respectively, “dematerialization” and “decarbonization”. This chapter will provide an introduction into industrial ecology and its implications for the electronics industry. Current activities, initiatives, and opportunities will also be explored, illustrating that the concomitant achievement of greater economic and environmental efficiency is indeed feasible in many cases. 111.2 Industrial Ecology Industrial ecology is an emerging field that views manufacturing and other industrial activity including forestry, agriculture, mining, and other extractive sectors, as an integral component of global natural systems. In doing so, it takes a systems view of design and manufacturing activities so as to reduce or, more desirably, eliminate the environmental impacts of materials, manufacturing processes, technologies, and products across their life cycles, including use and disposal. It incorporates, among other things, research involving energy supply and use, new materials, new technologies and technological systems, basic sciences, economics, law, management, and social sciences. The study of industrial ecology will, in the long run, provide the means by which the human species can deliberately and rationally approach a desirable long-term global carrying capacity. Oversimplifying, it can be thought of as “the science of sustainability”. The approach is “deliberate” and “rational”, to differentiate it from other, unplanned paths that might result, for example, in global pandemics, or economic and cultural collapse. The endpoint is “desirable”, to differentiate it from other conceivable states such as a Malthusian subsistence world, which could involve much lower population levels, or oscillating population levels that depend on death rates to maintain a balance between resources and population levels. Figure 111.1 illustrates how industrial ecology provides a framework for operationalizing the vision of sustainable development. As the term implies, industrial ecology is concerned with the evolution of technology and economic systems such that human economic activity mimics a mature biological system from the standpoint of being self- contained in its material and resource use. In such a system, little if any virgin material input is required, and little if any waste that must be disposed of outside of the economic system is generated. Energetically, the system can be open, just as biological systems are, although it is likely that overall energy consumption and intensity will be limited. FIGURE 111.1 Industrial ecology framework. ? 2000 by CRC Press LLC Although it is still a nascent field, a few fundamental principles are already apparent. Most importantly, the evolution of environmentally appropriate technology is seen as critical to reaching and maintaining a sustainable state. Unlike earlier approaches to environmental issues, which tended to regard technology as neutral at best, industrial ecology focuses on development of economically and environmentally efficient technology as key to any desirable, sustainable global state. Also, environmental considerations must be integrated into all aspects of economic behavior, especially product and process design, and the design of economic and social systems within which those products are used and disposed. Environmental concerns must be internalized into technological systems and economic factors. It is not sufficient to design an energy efficient computer, for example; it is also necessary to ensure that the product, its components, or its constituent materials can be refurbished or recycled after the customer is through with it—all of this in a highly competitive and rapidly evolving market. This consideration implies a comprehensive and systems-based approach that is far more fundamental than any we have yet developed. Industrial ecology requires an approach that is truly multidisciplinary. It is important to emphasize that industrial ecology is an objective field of study based on existing scientific and technological disciplines, not a form of industrial policy. It is profoundly a systems oriented and comprehensive approach which poses problems for most institutions—the government, riddled with fiefdoms; academia, with rigid departmental lines; and private firms, with job slots defined by occupation. Nonetheless, it is all too frequent that industrial ecology is seen as an economic program by economists, a legal program by lawyers, a technical program by engineers, and a scientific program by scientists. It is in part each of these; more importantly, it is all of these. Industrial ecology has an important implication, however, of special interest to electronics and telecommu- nications engineers, and thus deserving of emphasis. The achievement of sustainability will, in part, require the substitution of intellectual and information capital for traditional physical capital, energy, and material inputs. Environmentally appropriate electronics, information management, and telecommunications technol- ogies and services—and the manufacturing base that supports them—are therefore enabling technologies to achieve sustainable development. This offers unique opportunities for professional satisfaction, but also places a unique responsibility on the community of electrical and electronics engineers. We in particular cannot simply wait for the theory of industrial ecology to be fully developed before taking action. 111.3 Design for Environment Design for Environment (DFE) is the means by which the precepts of industrial ecology, as currently understood, can in fact begin to be implemented in the real world today. DFE requires that environmental objectives and constraints be driven into process and product design, and materials and technology choices. The focus is on the design stage because, for many articles, that is where most, if not all, of their life cycle environmental impacts are explicitly or implicitly established. Traditionally, electronics design has been based on a correct-by-verification approach, in which the environmental ramifications of a product (from manufac- turing through disposition) are not considered until the product design is completed. DFE, by contrast, takes place early in a product’s design phase as part of the concurrent engineering process to ensure that the environmental consequences of a product’s life cycle are understood before manufacturing decisions are committed. It is estimated that some 80 to 90% of the environmental impacts generated by product manufacture, use, and disposal are “locked-in” by the initial design. Materials choices, for example, ripple backwards towards environmental impacts associated with the extractive, smelting, and chemical industries. The design of a product and component selection control many environmental impacts associated with manufacturing, enabling, for example, substitution of no-clean or aqueous cleaning of printed wiring boards for processes that release ozone depleting substances, air toxics, or volatile organic compounds that are precursors of photochemical smog. The design of products controls many aspects of environmental impacts during use—energy efficient design is one example. Product design also controls the ease with which a product may be refurbished, or disassembled for parts or materials reclamation, after consumer use. DFE tools and methodologies offer a means to address such concerns at the design stage. Obviously, DFE is not a panacea. It cannot, for example, compensate for failures of the current price structure to account for external factors, such as the real (i.e., social) cost of energy. It cannot compensate for deficiencies ? 2000 by CRC Press LLC in sectors outside electronics, such as a poorly coordinated, polluting, or even non-existent disposal and material recycling system in some areas of the world. Moreover, it is important to realize that DFE recognizes environ- mental considerations as on par with other objective and constraints—such as economic, technological, and market structure—not as superseding or dominating them. Nonetheless, if properly implemented, DFE pro- grams represent a quantum leap forward in the way private firms integrate environmental concerns into their operations and technology. It is useful to think of DFE within the firm as encompassing two different groups of activities as shown in Fig. 111.2. In all cases, DFE activities require inclusion of life-cycle considerations in the analytical process. The first, which might be styled “generic DFE”, involves the implementation of broad programs that make the company’s operations more environmentally preferable across the board. This might include, for example, development and implementation of ‘‘green accounting” practices, which ensure that relevant environmental costs are broken out by product line and process, so that they can be managed down. The “standard components” lists maintained by many companies can be reviewed to ensure that they direct the use of environmentally appropriate components and products wherever possible. Thus, for example, open relays might be deleted from such lists, on the grounds that they “can’t swim”, and thus might implicitly establish a need for chlorinated solvent, as opposed to aqueous, cleaning systems. Contract provisions can be reviewed to ensure that suppliers are being directed to use environmentally preferable technologies and materials where possible. For example, are virgin materials being required where they are unnecessary? Do contracts, standards, and specifications clearly call for the use of recycled materials where they meet relevant performance requirements? Likewise, customer and internal standards and specifi- cations can be reviewed with the same goal in mind. The second group of DFE activities can be thought of as “specific DFE”. Here, DFE is considered as a module of existing product realization processes, specifically the “Design for X”, or DFX, systems used by many electronics manufacturers. The method involves creation of software tools and checklists, similar to those used in Design for Manufacturability, Design for Testability, or Design for Safety modules that ensure relevant environmental considerations are also included in the design process from the beginning. The challenge is to create modules which, in keeping with industrial ecology theory, are broad, comprehensive, and systems-based, yet can be defined well enough to be integrated into current design activities. The successful application of DFE to the design of electronic systems requires the coordination of several design and data-based activities, such as environmental impact metrics; data and data management; design optimization, including cost assessments; and others. Failure to address any of these aspects can limit the effectiveness and usefulness of DFE efforts. Data and methodological deficiencies abound, and the challenge is great, yet experience at world class companies such as AT&T, Digital, IBM, Motorola, Siemens Nixdorf, Volvo, and Xerox indicate that it can be done. AT&T, for example, is testing a draft DFE practice; baselining the environmental attributes of a telephone at different life cycle stages to determine where meaningful environmental FIGURE 111.2 Examples of DFE activities within the firm. ? 2000 by CRC Press LLC improvements in design can be achieved; and developing software tools that can inform environmentally preferable design decisions [Seifert, 1995]. In Sweden, the government and Volvo have developed a relatively simple Environment Priority Strategies for Environmental Design, or EPS, system which uses Environmental Load Units, or ELUs, to inform materials choices during the design process. In Germany, Siemens Nixdorf has developed an “Eco-balance” system to help it make design choices that reflect both environmental and economic requirements. Xerox is a world leader in designing their products for refurbishment using a product life extension approach. More broadly, the American Electronics Association (AEA) Design for Environment Task Force has created a series of White Papers discussing various aspects of Design for Environment and its implementation. The Microelectronics and Computer Technology Corporation (MCC) has published a comprehensive study [Lipp et al., 1993] of the environmental impacts of a computer workstation, which is valuable not only for its technical findings, but for the substantial data and methodological gaps the study process identified. The Society of Environmental Toxicology and Chemistry (SETAC) and others, especially in Europe, are working on a number of comprehensive life-cycle assessment (LCA) methodologies designed to identify and prioritize environmental impacts of substances throughout their life cycle. The International Organization for Standards (ISO) is in the process of creating an international LCA standard. The IEEE Environment, Health and Safety Committee, formed in July, 1992, to support the integration of environmental, health, and safety considerations into electronics products and processes from design and manufacturing, to use, to recycling, refurbishing, or disposal has held a series of annual symposium on electronics and the environment. The proceedings from these symposia are valuable resources to the practitioners of DFE. 111.4 Environmental Implications for the Electronics Industry Global concerns and regulations associated with environmental issues are increasingly affecting the manufac- turing and design of electronic products, their technology development, and marketing strategies. No point illustrates this better than the German Blue Angel Eco-Labeling scheme for personal computers (the Blue Angel is a quasi-governmental, multi-attribute eco-labeling program). The Blue Angel requirements are numerous and span the complete life-cycle of the computers. Examples of some the requirements include: modular design of the entire system, customer-replaceable subassemblies and modules, use of non-halogenated flame retardants, and take back by manufacturers at the end of the product life. Market requirements such as these, focused on products and integrating as they do environmental and technology considerations, cannot possibly be met by continuing to treat environmental impact as an unavoidable result of industrial activity, i.e., as overhead. These requirements make environmental concerns truly strategic for the firm. Perhaps the most familiar example of “a new generation of environmental management” requirements which will have enormous effects on electronics design is “product take back”. These programs, such as the one mentioned in the Blue Angel labeling scheme, are being introduced in Germany and other countries for electronics manufacturers. They generally require that the firm take its products back once the consumer is through with them, recycle or refurbish the product, and assume responsibility for any remaining waste generated by the product. Other members of the European Union and Japan are among others considering such “take back” requirements. Similarly, the emergence of the international standard, ISO 14000, which includes requirements for environmental management systems, methodologies for life cycle assessment and environmental product specifications will have vast implications for the electronics industry. Though technically voluntary, in practice these standards in fact become requirements for firms wishing to engage in global commerce. These examples represent a global trend towards proactive management of business and products in the name of the environment. 111.5 Emerging Technology New tools and technologies are emerging which will influence the environmental performance of electronic products and help the industry respond to the regulatory “push” and the market “pull” for environmentally responsible products. In the electronics industry, technology developments are important not only for the end-products, but ? 2000 by CRC Press LLC for components, recycling, and materials technology as well. Below is a brief summary of technology develop- ments and their associated environment impacts as well as tools to address the many environmental concerns facing the industry. The electronics industry has taken active steps toward environmental stewardship, evidenced by the formu- lation of the IEEE Environment, Safety and Health Committee, the 1996 Electronics Industry Environmental Roadmap published by MCC, and chapters focused on environment in The National Technology Roadmap for Semiconductors. Moves such as this, taken together with the technical sophistication of control systems used in manufacturing processes, have allowed the electronics industry to maintain low emission levels relative to some other industries. Despite the industry’s environmental actions, the projected growth in electronics over the next 10 to 20 years is dramatic and continued technological innovation will be required to maintain historically low environmental impacts. Moreover, the rapid pace of technological change generates concomi- tantly high rates of product obsolescence and disposal, a factor that has led countries such as Germany and the Netherlands to focus on electronics products for environmental management. Environmental considerations are not, of course, the only forces driving the technological evolution in the electronics industry. Major driving forces, as always, also include price, cost, performance, and market/regula- tory requirements. However, to the extent that the trend is toward smaller devices, fewer processing steps, increased automation, and higher performance per device, such evolution will likely have a positive environ- mental impact at the unit production level, i.e., less materials, less chemicals, less waste related to each unit produced. Technology advances that have environmental implications at the upstream processing stage may well have significant benefits in the later stages of systems development and production. For example, material substitution in early production stages may decrease waste implications throughout the entire process. Since both semiconductors and printed wiring boards are produced in high volume and are present in virtually all electronic products ranging from electronic appliances, to computers, automotive, aerospace, and military applications, we will briefly examine the impact of these two areas of the electronic industry. Integrated Circuits The complex process of manufacturing semiconductor integrated circuits (IC) often consists of over a hundred steps during which many copies of an individual IC are formed on a single wafer. Each of the major process steps used in IC manufacturing involves some combination of energy use, material consumption, and material waste. Water usage is high due to the many cleaning and rinsing process steps. Absent process innovation, this trend will continue as wafer sizes increase, driving up the cost of water and waste water fees, and increasing mandated water conservation. Environmental issues that also require attention include the constituent materials for encapsulants, the metals used for connection and attachment, the energy consumed in high-temperature processes, and the chemicals and solvents used in the packaging process. Here, emerging packaging technologies will have the effect of reducing the quantity of materials used in the packaging process by shrinking IC package sizes. Increasing predominance of plastic packaging will reduce energy consumption associated with hermetic ceramic packaging. Printed Wiring Boards Printed wiring boards represent the dominant interconnect technology on which chips will be attached and represents another key opportunity for making significant environmental advances. PWB manufacturing is a complicated process and uses large amounts of materials and energy (e.g., 1 MegaW of heat and 220 kW of energy is consumed during fabrication of prepeg for PWBs). On average, the waste streams constitutes 92%—and the final product just 8%—of the total weight of the materials used in PWB production process. Approximately 80% of the waste produced is hazardous and most of the waste is aqueous, including a range of hazardous chemicals. Printed wiring boards are not recycled because the removal of soldered sub- assemblies is costly and advanced chip designs require new printed wiring boards to be competitive. As a result, the boards are incinerated and the residual ash buried in hazardous waste landfills due to the lead content (from lead solder). ? 2000 by CRC Press LLC 111.6 Tools and Strategies for Environmental Design The key to reducing the environmental impact of electronic products will be the application of DFE tools and methodologies. Development of CAD/CAM tools based on environmental impact metrics, materials selection data, cost, and product data management are examples of available or clearly foreseeable tools to assist firms in adopting DFE practices. These tools will need to be based on life cycle assessment, the objective process used to evaluate the environmental impacts associated with a product and identify opportunities for improvement. Life cycle assessment seeks to minimize the environmental impact of the manufacture, use, and eventual disposal of products without compromising essential product functions. Figure 111.3 shows the life stages that would be considered for electronic products (i.e., the life cycle considered has been bounded by product design activities). The ability of the electronics industry to operate in a more environmentally and economically efficient mode, use less chemicals and materials, and reduce energy consumption will require support tools that can be used to evaluate both product and process designs. To date, many firms are making immediate gains by incorporating basic tools like DFE checklists, design standards and internal databases on chemicals and materials, while other firms are developing sophisticated software tools that give products environmental scores based on the product’s compliance with a set of predetermined environmental attributes. These software tools rely heavily on envi- ronmental metrics (typically internal to the firm) to assess the environmental impact and then assign a score to the associated impact. Other types of tools that will be necessary to implement DFE will include tools to characterize environmental risk, define and build flexible processes to reduce waste, and support dematerialization of processes and products. The following sections provide a brief review of design tools or strategies that can be employed Design Tools Environmental design tools vary widely in the evaluation procedures offered in terms of the type of data used, method of analysis, and the results provided to the electronic designer. The tool strategies range in scope from assessment of the entire product life cycle to the evaluation of a single aspect of its fabrication, use, or disposal. Today’s DFE tools can be generally characterized as either life cycle analysis, recyclability analysis, manufacturing analysis, or process flow analysis tools. FIGURE 111.3 Design for environment: systems-based, life cycle approach. ? 2000 by CRC Press LLC The effectiveness of these design tools is based both on the tool’s functionality as well as its corresponding support data. One of the biggest challenges designers face with regards to DFE is a lack of reliable data on materials, parts, and components needed to adequately convey the impact and trade-offs of their design decisions. To account for these data deficiencies, a number of environmental design tools attempt to use innovative, analytical methods to estimate environmental impacts: while necessary, this indicates they must be used with care and an understanding of their assumptions. Although DFE provides a systems-based, life cycle approach, its true value to the system designer is lost unless the impact of DFE decisions on other relevant economic and performance measures (i.e., cost, electrical performance, reliability, etc.) can be quickly and accurately assessed. Trade-off analysis tools that have DFE embedded can perform process flow-based environmental analysis (energy/mass balance, waste stream analysis, etc.) concurrently with non-environmental cost and performance analysis so that system designers can accu- rately evaluate the impact of critical design decisions early. Design Strategies Design strategies such as lead minimization through component selection, and the reduction of waste resulting from rapid technological evolution through modular design, help to minimize the environmental impact of electronic products. Although at this time no suitable lead-free alternatives exist for electronic interconnections, designers can still minimize the lead content of electronic designs. Surface mount technology requires less solder than through-hole technology. New interconnection technologies, such as microball grid array and direct chip attachment, also require less solder. The environmental benefits increase with the use of these advanced interconnection technologies. The rapid advancement of the electronics industry has created a time when many products become obsolete in less than five years’ time. Electronic products must be built to last, but only until it is time to take them apart for rebuilding or for reuse of material. This means employing modular design strategies to facilitate disassembly for recycle or upgrade of the product rather than replacement. Designers must extend their views to consider the full utilization of materials and the environmental impact of the material life cycle as well as the product life cycle. Conclusion The diverse product variety of the electronics industry offers numerous opportunities to curtail the environ- mental impact of the industry. These opportunities are multidimensional. Services made possible through telecommunications technology enable people to work from home reducing emissions that would be generated by traveling to work. Smaller, faster computers and the Internet require less material usage, reducing the energy demand during processing and waste generated during fabrication. All these represent examples of how the electronics industry provides enablers of sustainability. Global concerns and regulations associated with environmental issues are increasingly affecting the manu- facturing and design of the electronics industry. Environmental management standards, “take back” programs, ISO 14000 standards development activity, and eco-label requirements represent a sample of the initiatives driving the industries move to more environmentally efficient practices. While the industry has initiated some activities to address environmental concerns, the future competitiveness of the industry will depend on improve- ments in environmental technology in manufacturing, accurate assessment of the environmental impact of products and process, and design products that employ design for environment, reuse, and recycleability. Industrial ecology offers a framework for analyzing the environmental effects of the electronics industry which is complicated by the rapid pace of change. Acknowledgements This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. ? 2000 by CRC Press LLC Disclaimer This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. Defining Terms Decarbonization: The reduction, over time, of carbon content per unit energy produced. Natural gas, for example, produces more energy per unit carbon than coal; equivalently, more CO 2 is produced from coal than from natural gas per unit energy produced. Dematerialization: The decline, over time, in weight of materials used in industrial end products, or in the embedded energy of the products. Dematerialization is an extremely important concept for the environ- ment because the use of less material translates into smaller quantities of waste generated in both production and consumption. Design for environment (DFE): The systematic consideration of design performance with respect to envi- ronment over the full product and process life cycle from design through manufacturing, packaging, distribution, installation, use, and end of life. It is proactive to reduce environmental impact by addressing environmental concerns in the product or process design stage. Eco-label: Label or certificate awarded to a product that has met specific environmental performance require- ments. Some of the most widely known eco-labels include Germany’s Blue Angel, Nordic White Swan, and U.S. Green Seal. Industrial ecology: The objective, multidisciplinary study of industrial and economic systems and their linkages with fundamental natural systems. ISO 14000: Series of international standards fashioned from the ISO 9000 standard which includes require- ments for environmental management systems, environmental auditing and labeling guidelines, life cycle analysis guidelines, and environmental product standards. Life cycle assessment (LCA): The method for systematically assessing the material use, energy use, waste emissions, services, processes, and technologies associated with a product. Product take back: Program in which manufacture agrees to take back product at the end-of-life (typically at no cost to the consumer) and disposal of product in an environmentally responsible matter. Related Topic 25.3 Application-Specific Integrated Circuits References B.F. Dambach and B.A. Allenby, “Implementing design for environment at AT&T,” Total Quality Environmental Management, 4, 51–62, 1995. T.E. Graedel and B.R. Allenby, Industrial Ecology, Englewood Cliffs, N.J.: Prentice-Hall, 1995. S. Lipp, G. Pitts, and F. Cassidy, Eds. “A life cycle environmental assessment of a computer workstation,” Environmental Consciousness: A Strategic Competitiveness Issue for the Electronics and Computer Industry, Austin, Tex.: Microelectronics and Computer Technology Corporation. S. Pederson, C. Wilson, G. Pitts, and B. Stotesbery, Eds. Electronics Industry Roadmap, Austin, Tex.: Microelec- tronics and Computer Technology Corporation, 1996. ? 2000 by CRC Press LLC L. Seifert, “AT&T technology and the environment,” AT&T Tech. J., 74, 4–7, 1995. World Commission on Environment and Development, Our Common Future, Oxford: Oxford University Press, 1987. Further Information The IEEE Environment, Health and Safety Committee annually sponsors and publishes the proceeding of the International Symposium on Electronics and the Environment. These proceedings are a valuable resource for practitioners of DFE. The National Technology Roadmap for Semiconductors, published by the Semiconductor Industry Association contains information on the environmental impacts of semiconductor fabrication as well as initiatives begun to address these concerns. The AT&T Technical Journal has a dedicated issue on Industrial Ecology and DFE entitled AT&T Technology and the Environment, volume 74, no. 6, November/December 1995. Other suggested reading: American Electronics Association, “The hows and whys of design for the environment,” 1993. B.R. Allenby and D.J. Richards, Eds., The Greening of Industrial Ecosystems, Washington, D.C.: National Academy Press, 1994. P. Eisenberger, Ed., Basic Research Needs for Environmentally Responsive Technologies of the Future, Princeton, N.J.: Princeton Materials Institute, 1996. T.E. Graedel and B.R. Allenby, Design for Environment, Englewood Cliffs, N.J.: Prentice-Hall, 1996. ? 2000 by CRC Press LLC