[] TL: CLIMBING OUT OF THE OZONE HOLE (GP) SO: GREENPEACE INTERNATIONAL (GP) DT: October, 1992 Keywords: environment greenpeace atmosphere ozone alternatives chemicals research chlorine / A Preliminary Survey of Alternatives to Ozone-Depleting Chemicals Edited by Sheldon Cohen and Alan Pickaver GREENPEACE INTERNATIONAL OCTOBER 1992 CONTENTS ACKNOWLEDGEMENTS F O R E W O R D EXECUTIVE SUMMARY PART ONE: THE NATURE OF THE PROBLEM INTRODUCTION CHAPTER I: THE CRISIS DEEPENS: RECENT SCIENTIFIC DEVELOPMENTS CHAPTER II: HCFCs AND HFCs: PART OF THE PROBLEM, NOT PART OF THE SOLUTION CHAPTER III: GREENPEACE'S RESPONSE TO THE OZONE CRISIS PART TWO: SURVEY OF ALTERNATIVES CHAPTER IV: REFRIGERATION AND COOLING CHAPTER V: SOLVENTS CHAPTER Vl: AEROSOLS CHAPTER VlI: FOAMS CHAPTER VIII: FIREFIGHTING ABOUT THE WRITERS, EDITORS, AND REVIEWERS ACKNOWLEDGEMENTES We gratefully acknowledge the many people who contributed to this report. In addition to the individuals mentioned on page 41, we would like to thank Alexandra Allen, Cindy Baxter, Thomas Belazzi, Karla Bell, Katinka Broersen, Melanie Duchin, Meg Duskin, Lisa Finaldi, Lyn Goldsworthy, Tracy Heslop, Paul Hohnen, Karen Johnson, Andrew Kerr, Rob Lindgren, Wolfgang Lohbeck, John Mate, Yasuko Matsumoto, Corin Millais, Kelly Rigg, Barbie Robinson, Kevin Stairs, Kim Stanley and Marion Taesch. Very special thanks goes out to Gwenan Richards for her tireless persistence in the production of this report. FOREWORD The destruction of the ozone layer, primarily by chlorine- and bromine-based CFCs and halons, reflects in large part the initial failure of governments and chemical companies to determine the environmental consequences of products or to acknowledge the existence of alternatives to chemicals which destroy ozone. The observed evidence of the damage being wrought on our life-protecting ozone layer continues to outstrip scientific predictions. The case for an immediate ban on all chemicals which destroy ozone is strengthened with each new announcement of ever-worsening ozone depletion. Even more worrying is the knowledge that there are thresholds past which exponential ozone depletion occurs, such as the development of the Antarctic ozone hole. It can take years for ozone-depleting chemicals (ODCs) to make their way to the stratosphere and begin destroying ozone. Significant quantities of these chemicals have already been released, but have not yet reached the stratosphere. We know that we therefore face worsening ozone depletion and worsening impacts for at least the next decade. What we do not know is whether this inevitable increase in ODCs in the stratosphere will spark further exponential ozone depletion. The threat is huge. The extra ultraviolet radiation allowed through a depleted ozone layer is damaging to all forms of life on earth. We have long passed the point where an immediate ban on all chemicals which damage the ozone layer has become an environmental and human health necessity. This would be true even if alternatives were not available. In the interests of informed public debate, this report details many of the existing alternatives to ODCs. Greenpeace's research has revealed a broad range of safer options covering the overwhelming majority of uses of these chemicals. Many of these alternatives have been largely neglected by industry and governments in their push to promote two other families of environmentally damaging chemicals HCFCs and HFCs. The Alternatives Report represents a preliminary survey of available alternatives. As such, it does not identify alternatives for every specific application of chemicals which deplete the ozone layer. Rather, it is intended to help fundamentally change the terms of the debate concerning ODCs. It is a direct challenge to the chemical companies' contention that their preferred chemical substitutes, HCFCs and HFCs, are the only viable options if society is to rapidly move away from ODCs. Indeed, consideration of the alternatives must not be narrowly confined to chemical substitutes, but rather encompass the entire range of alternatives, including non-chemical ones. It must be noted however that further scientific research could eliminate some of the alternatives in this report as viable options. Greenpeace does not specifically endorse per se any of the alternatives discussed in this report. It must be recognised that few alternatives to ODCs will be entirely without environmental impact. Greenpeace believes that the development of alternatives must be based on the following general principles: . Changes in consumption patterns and production processes must be given the highest consideration. A fundamental evaluation of the necessity of any current use of ODCs is essential given the severity of the ozone crisis. . All alternatives should be considered. However, only those which meet the following criteria should be viewed as viable. - no chlorine or bromine containing compounds - no compounds which contribute, or are suspected of contributing, to ozone depletion - no substances or technologies which may contribute significantly to global warming - energy use must be minimised as much as possible - technologies which use or result in synthetic, persistent and/or toxic substances should be avoided . Accelerated research and development of alternatives by industry and governments must be given the highest priority, particularly in areas where alternatives are not yet widely available on a commercial basis. . The use of alternatives should be subject to regular, independent, international monitoring for potential environmental impacts. These reviews should take into account such issues as possible toxicity, energy efficiency, chemical lifetimes, cost, volume of use and possible emissions. To ensure objectivity, the public, independent scientists, and NGOs should be closely involved in the review process. The above criteria for evaluating alternatives embody the concept of clean-production technologies which are designed to employ only reusable and renewable materials and to conserve energy, water, soil and other resources. Environmental protection must become an integral component of all production systems; in short, production processes should be compatible with the health and survival of the Earth's ecosystems. Activities must be non-polluting, preserve diversity in nature, and support the ability of future generations to meet their needs. Many of the alternatives to ODCs may be considered environmentally safer. Some of them, however, do not fully meet the criteria of clean production, although in many cases developments are moving in that direction. For the purposes of this report, the alternatives available in each use sector have been preliminarily divided into 'safest known alternatives' and 'others'. Alternatives in the latter category may, in the short term, cause less overt damage to the environment than the use of ODCs. However, their use should not exclude further research and development of other alternatives which will meet the criteria of clean production. It is important to note that chlorine-based ozone depleters such as CFCs are only part of an environmentally destructive chlorine industry, which includes such products as polychlorinated biphenyls (PCBs) and polyvinyl chloride (PVC). Because of the diffuse nature of information on alternatives, time constraints and the pace of technological innovation, some areas of ODCs use were either omitted or were not addressed in as much detail as would have been preferred. Greenpeace therefore proposes that the availability of alternatives be the subject of regular review. Economic aspects of alternatives are not discussed in detail in this report. Any references to economic costs refer to assessments by parties other than Greenpeace and implies no Greenpeace agreement. Until conventional economic models incorporate fully the environmental costs of a particular activity, they must be considered as inadequate and a cause of continuing environmental damage. Specifically, Greenpeace rejects the proposition that environmental policies must always be cost-effective under current market conditions. While many alternatives are already cost-effective, others would be so if cost were more broadly defined to include externalities. In any event, the critical question is what is the cost of inaction? The magnitude of the ozone crisis is such that huge-scale government intervention is justified to ensure a total and immediate ban on production of all ODCs. EXECUTIVE SUMMARY THE NATURE OF THE PROBLEM Virtually every new scientific finding on ozone depletion shows the problem is worse than previously predicted. In early 1992, scientific studies recorded ozone loss as high as 10-15% over the highly populated mid-latitudes of the Northern Hemisphere, and as high as 20% over the Arctic. The formation of an ozone hole over the Northern Hemisphere in the near future, and possibly as early as 1993, now appears inevitable. According to the United Nations Environment Programme (UNEP), chlorine-based CFCs and other chemicals previously released into the atmosphere will result in worsening ozone depletion till at least the year 2000. Scientists have painted the grimmest of pictures in terms of the human health and environmental impacts of ozone loss. These include skyrocketing rates of skin cancer and cataracts, increases in the severity and incidence of infectious diseases, the possible impairment of vaccination programmes and dramatic drops in phytoplankton populations, to name a few. Joe Farman, the British scientist credited with discovery of the Antarctic ozone hole, has likened the ozone crisis to a science fiction plot. In light of the severity of the ozone crisis, how is it possible that ozone-depleting chemicals (ODCs) are still being produced? Part of the answer lies in the 'go-slow' approach by governments, based largely on the availability of technical options. But we cannot afford to continue producing ODCs until specific alternatives are found for every use. The urgency of the situation demands a full, immediate ban on the production of all chemical compounds which are, or are suspected of being, ODCs. On balance, the threat to the world's populations and economies due to inaction far outweighs the threat to the industries involved if a ban on ODCs is immediately enacted. An immediate ban would be an imperative even if alternatives were not yet widely available. Fortunately, they are. In Greenpeace's view, by far the most important single obstacle to an immediate ban on all ODCs has been industry's carefully orchestrated control of the debate around their alternatives. The flawed and short-sighted argument that wide-scale production of HCFCs and HFCs must be permitted if CFCs are to be phased out rapidly has been accepted with little debate, and industry has moved full steam ahead with its production plans. Recent scientific findings conclude however that HCFCs will have a much greater impact on ozone depletion than previously estimated, particularly over the next two decades which present the period of maximum threat to the ozone layer. Also, along with HFCs, they could greatly exacerbate the global warming problem. These significant environmental impacts are in large part being ignored, along with the fact that safer alternatives already exist. Such additional threats to the global environment (by HCFCs and HFCs) are not only unacceptable, but simply unnecessary. As this report documents, a very broad range of alternatives is available today for the vast majority of applications where HCFC or HFC use is being proposed or already occurring. Many of these alternatives are already competitive, and in some cases even surpass HCFC/HFC options, in terms of costs and efficiency. Prime examples would be the wide use of no-clean, aqueous, and semi-aqueous cleaning processes for electronics equipment; and propane- and ammonia-based refrigeration systems. There is good reason to believe that prospects for reducing costs and enhancing efficiency and performance will improve even further in the near-term. A brief summary of alternatives for all five major industry use sectors is given below. 2 ALTERNATIVES (a) Refrigeration There is a wide range of alternative refrigeration technologies. These include different types of refrigerants and refrigeration cycles. Some, such as ammonia-based vapour compression systems and water-based evaporative cooling systems are already in wide use. Others such as propane-based vapour compression systems, helium- based Stirling cycle systems, and zeolite-based adsorption systems are either beginning to enter commercial markets, or will do so in the near-term. This is rather remarkable in itself given that the amount of research and development devoted to these technologies has been at best inadequate. In many cases, the reasons that alternative technologies are not already widely used are more a matter of insufficient funding and political commitment rather than technical obstacles. It is important to note that many alternative refrigeration systems are competitive with, or even superior to, conventional vapour compression systems using CFCs, HCFC-22 or HFC- 134a in terms of costs and efficiency. When considering alternatives to CFC use, questions need to be raised about the necessity of some refrigeration and cooling applications. Some current applications can be replaced by simpler, low-technology alternatives such as better ventilation systems. Some of the total refrigeration and air-conditioning 'capacity' could be eliminated by simply using fewer and smaller units. (b) Solvents Alternatives are now in wide commercial use for virtually every solvent application where CFC-113 or methyl chloroform have been employed in electronics, metal and precision cleaning. These alternatives include processes which eliminate the need for cleaning by using 'no-clean' fluxes and controlled atmospheric soldering; aqueous and semi-aqueous cleaning methods; and specialised cleaning methods (e.g. ice particle sprays, and pressurised gases such as air and nitrogen). Many of the world's largest computer companies have already completely eliminated the use of ODCs as solvents and others are planning to do so in the 1992/1993 period. (c) Aerosols Since the late 1970s, CFC use in the aerosols sector has dramatically diminished. There is a wide variety of alternatives to CFCs being used. They include, among others, non-spray (e.g. roll-ons, solid sticks) and mechanical spray dispensers (e.g. trigger pumps), compressed gas and hydrocarbon propellants, and dry powder inhalers and nebulizers for medical applications. The use of CFCs in metered-dose inhalers for asthmatic patients is generally recognised as an "essential use." However, a combination of alternatives (e.g. dry powder inhalers) and CFC recycling should eliminate any need for new CFC production. (d) Firefighting A wide range of alternatives to halons in firefighting are currently in use, including improved fire prevention and loss reduction practices and alternative extinguishing agents and technologies. Fire risks and damage can be reduced through a number of measures (e.g. fire-resistant materials and early-detection surveillance systems). Several alternative extinguishing agents are already widely used including carbon dioxide, water, foam and powders. These agents, sometimes used in combination, can replace halons in nearly all portable and fixed extinguishing systems. The new carbon dioxide/nitrogen/argon mixture could be a major breakthrough in replacing Halon 1301 in fixed systems. This would mean that in the very near future, halon use could be completely eliminated. At present, some applications, such as protection of aircraft cabins, are still considered 'essential uses.' However, even if there were no alternatives for such 'essential uses' in the near future, the existing halon bank would certainly be more than adequate to meet these needs. There is no justification for continued halon production. (e) Foams Long-term, the acceptability of foam products must be reassessed. Polyurethanes and polystyrenes, as well as isocyanates used for polyurethane foam production, are themselves environmentally damaging. Furthermore, some of the uses to which these products are put are unnecessary (e.g. packaging, cushions, steering wheels, and headrests in automobiles). Many alternatives to foams are already widely used. They include a broad range of traditional insulating materials, such as fibreglass and fibreboard, paper and cardboard as packaging materials, and products made of rubber and leather. All of these are widely available and although the insulation materials have higher thermal conductivities, the use of thicker sections and special designs, such as insulation panel cover layers, will compensate. Alternative foam-blowing agents, including carbon dioxide, carbon monoxide, water and pentane are being used increasingly in foam production. Other technologies such as vacuum and silicon aerogel insulation panels should become commercially available in the near-term. 3 GREENPEACE'S RESPONSE TO THE OZONE CRISIS Throughout the ozone crisis, industry and government decision- makers have consistently allowed short-sighted concerns to come before human health and the needs of the environment. Greenpeace advocates a different type of approach - a "precautionary approach" - toward protecting the ozone layer. This is, in fact, the approach to which governments are committed in Article 2 of the 1985 Vienna Convention for the Protection of the Ozone Layer. An effective response to the ozone crisis must include, among other measures: . An immediate, 100% production ban on all ozone-depleting chemicals (ODCs); . Mandatory recapture of ODCs; . Abandonment of plans for commercial production of HFCs; and . Active research, development, and promotion of alternatives by governments and industry as a high priority. 4 CONCLUSIONS A broad range of alternatives to chemicals which destroy the ozone layer already exists. Yet although ozone depletion continues to outstrip even the most pessimistic scientific predictions, international action to avert disaster is being directed not by environmental imperatives but by the agenda of the chemical industry. This agenda attempts to delay phase-out of ozone depleting chemicals and demands acceptance of a narrow range of preferred alternatives (HCFCs and HFCs) which themselves destroy ozone or which significantly expand the threat of global warming. As a consequence of industry's predominance over the alternatives debate, there has been little investigation of alternatives other than those preferred by industry. However, as this report shows, a plethora of safer alternatives is already commercially available in every sector and for virtually all applications where ozone-depleting chemicals have traditionally been used. In many cases, these alternatives are competitive or even superior in terms of cost and efficiency. Greenpeace contends that an immediate ban on all chemicals that deplete ozone is not only essential, but commercially feasible and without the need to rely on HCFCs and HFCs. Governments have accepted the environmental necessity of taking firm action to protect the ozone layer. This report shows that industry's arguments for delayed phase-out dates and acceptance of HCFCs and HFCs can no longer be accepted. Ozone depletion is perhaps the single most dangerous threat facing humanity. Even if alternatives did not exist, logic would demand an immediate ban. This report shows conclusively that such alternatives do exist. Greenpeace urges the governments of the world to consider the evidence laid out in this report, and agree to an immediate halt to all production of these life- threatening chemicals and to urgently develop and promote alternatives. PART ONE: THE NATURE OF THE PROBLEM INTRODUCTION Ozone depletion, caused primarily by the emission of CFCs and other chlorine- and bromine-based compounds, is one of the most urgent crises facing our planet. To better understand this crisis, governments have undertaken intensive scientific investigations. For example, hundreds of the world's top atmospheric, medical, and engineering experts from dozens of countries participated in the 1991 United Nations Environment Programme (UNEP) assessment of ozone depletion. And more recently, two in depth studies of Northern Hemisphere ozone loss were completed in the spring of 1992, one involving seventeen European countries and the other, a number of U.S. Government agencies 1. Paradoxically, despite such a mammoth effort to expand scientific understanding, no other major environmental problem has proven so intractable to scientific forecasting. Computer models have consistently underestimated the rate and extent of ozone depletion 2. One prediction about which scientists seem certain, however, is that ozone depletion will continue to worsen for at least a decade and probably longer 3. Today's unprecedented levels of ozone depletion do not yet reflect the period of highest global production of ozone-depleting chemicals (ODCs), since it takes up to two decades for these chemicals to reach the stratosphere 4. Even if production of ODCs were to end tomorrow, chlorine would continue to build up in the stratosphere, peaking around the year 2000 at 4.1 parts per billion by volume (ppbv) - roughly seven times higher than natural background levels 5. Because of the long lifetimes of ODCs, ozone depletion would continue for much longer. For example, the Antarctic ozone hole is expected to form during each Southern hemisphere spring for most of the next century 6. The extra ultraviolet radiation allowed through a depleting ozone layer is harmful to all forms of life on Earth. Worsening ozone depletion is inevitable, and the danger of thresholds past which further exponential ozone depletion occurs will expand as long as any emissions of ODCs continue. The magnitude and severity of the threat demands one solution: a full and immediate ban on the production of all ODCs. The threat to the future of life on Earth is far greater than the threat to the industries involved if a ban were immediately imposed. In addition to the real and severe impacts of ozone depletion, there are other independent grounds for such a ban. Organochlorine and other organohalogen compounds have long been recognised as pollutants responsible for a range of damaging direct impacts on human health and on the marine environment. They are toxic, persistent and liable to bioaccumulate. As this report shows, viable alternatives already exist for virtually all uses of ozone-depleting chemicals. Moreover, an immediate ban would force the accelerated development of alternatives in the few areas where they are not yet widely available on a commercial basis. Unfortunately, time and again, the governmental response to the ozone crisis has been inadequate. The Vienna Convention and its Montreal Protocol of 1987 were hailed as a landmark, a model for future environmental protection regimes. However, it quickly became apparent that the agreement would not protect the ozone layer from further, indefinite deterioration 7. In fact, just five months after coming into force, the Protocol was declared inadequate by the Signatory Governments 8. Despite a growing catalogue of ominous scientific signals during 1987-1990, including a growing Antarctic ozone hole, increasingly severe mid-latitude depletion and signs of significant Arctic ozone depletion, when the Parties to the Montreal Protocol met in London in 1990 to strengthen the Treaty, they again took inadequate action. The revised Protocol still allowed for a further ten years of CFC production and 20 years in the case of developing countries. No binding limitations whatsoever were placed on hydrochlorofluorocarbons (HCFCs), a family of ozone-depleting chemicals being actively promoted by industry as substitutes for CFCs 9. There is one obvious reason why governments have failed to take the responsible course and immediately ban all ODCs: they carry instructions from the industrial lobby rather than the people at large. Government positions are derived in large part from lobby pressure to protect short-term industrial interests rather than to protect the environment and human health. The desirability of maintaining the protective umbrella which permits the continuation of life on Earth is ignored by a "government for the industry," not a "government for the inhabitants of the planet". This undue influence on governments has been exerted by a relatively small core of about a dozen industrial companies which manufacture ODCs. These companies have played an active role in controlling the debate around alternatives to ODCs, using a variety of methods. These include large scale public relations efforts; redesignating names of ozone-depleting chemicals; down-playing environmental impacts of their preferred substitute chemicals; and halting nearly all research on alternatives in the early 1980s. In short, industry has created a false perception that only a very narrow range of viable alternatives to ODCs exists, in an apparent effort not only to forestall the CFC regulatory process, but also to promote the two families of environmentally unacceptable chemical substitutes, HCFCs and hydrofluorocarbons (HFCs). HCFCs are significant ozone-depleters in the short-term, while both chemical groups are powerful global warming gases. Greenpeace has produced the ALTERNATIVES REPORT in order to correct this false perception, by providing decision-makers and the public with crucial and often little-known information on the broad range of viable alternatives to ODCs. Until now, information on alternatives has been highly diffuse and has not been properly compiled or examined by governments, either independently or through the Montreal Protocol Assessment Process. The 1991 UNEP Technology and Economic Assessment Panel was charged with systematically reviewing available alternatives to ozone depleters. However, its inadequate terms of reference and somewhat biased composition ensured undue emphasis on HCFC/HFC and 'in-kind' (i.e. 'drop in') substitute paths. Many of the technologies described in this report, such as helium-based Stirling cycle refrigeration and evaporative cooling were insufficiently addressed and in some cases completely overlooked. This is not surprising since the interests of ODC-producing companies were heavily represented on the UNEP Committees. In addition, many of the alternatives discussed in this report are not attractive to industry because they cannot be patented. In fact, many are non-chemical alternatives. They include such diverse options as paper and cardboard packaging materials; water-based cleansing methods for electronics components; alternative refrigerants such as helium and propane; and manual pump spray mechanisms. The ALTERNATIVES REPORT is a preliminary survey. Its main purpose is to motivate governments and industry to evaluate, develop and promote alternatives as a high priority, particularly in the few areas where these alternatives are not yet widely available. The report focuses primarily on alternatives that are currently in commercial production. Others, which could be brought on-line rapidly given the proper commitment, are also discussed. The survey of alternatives (Part Two of the report) is preceded by chapters outlining the current state of scientific understanding, the serious problems associated with HCFCs and HFCs, and Greenpeace's response to the ozone crisis. References to Introduction 1 European Arctic Stratospheric Ozone Expedition (EASOE) and Airborne Arctic Stratospheric Expedition (AASE II). 2 Transcripts of testimony before the U.S. Senate Subcommittee on Science, Technology, and Space, Washington D.C., 16 April 1991. 3 United Nations Environment Programme (UNEP), Executive Summary, Science Assessment of Stratospheric Ozone, 1991. 4 German Bundestag, Protecting the Earth's Atmosphere: An International Challenge (Bonn, 1989). 5 UNEP, 1991. 6 World Meteorological Organisation: Scientific Assessment of Stratospheric Ozone, 1988. 7 UNEP, 1991. 8 Helsinki Declaration on the Protection of the Ozone Layer, May 1989. 9 Greenpeace International, 'The Failure of the Montreal Protocol'. (Amsterdam, June 1990). CHAPTER I THE CRISIS DEEPENS: RECENT SCIENTIFIC DEVELOPMENTS Scientific findings in 1991 and 1992 provide irrefutable evidence that the ozone crisis is rapidly worsening. These findings come from a number of sources, including analysis of reprocessed data (1978-1990) from the Total Ozone Mapping Spectrometer (TOMS) aboard the Nimbus 7 satellite; the 1991 United Nations Environment Programme (UNEP) Science Assessment; the 1991 UK Stratospheric Ozone Review Group (SORG) Report; the 1991-1992 U.S. Airborne Arctic Stratospheric Expedition (AASE II); and the European Arctic Stratospheric Ozone Expedition (EASOE). Ozone depletion is now being recorded globally, from Antarctica to the Arctic, in the tropics and in mid-latitude regions. And as the depletion continues to worsen, new scientific evidence shows that other mechanisms in the stratosphere are weakening the atmosphere's ability to recover from periods of ozone depletion. 1 In Antarctica, four of the past five years have seen the development of deep and extensive ozone holes. On 9 October 1991, NASA announced that stratospheric ozone over Antarctica had reached the lowest level ever recorded - 110 Dobson units. Normal ozone levels over the region are generally around 500 Dobson units 2. However, ozone depletion is no longer merely a Southern hemisphere problem. With the completion of two major Northern hemisphere studies in early 1992, it became apparent that an Arctic ozone hole is also likely to develop during at least some Northern springs in the future - possibly as early as 1993 3. In January 1992, the AASE II study found the highest levels of chlorine monoxide (ClO) ever recorded in the stratosphere above eastern Canada and northern New England. ClO is the reactive form of chlorine that triggers exponential ozone loss. The AASE II findings indicated that such quantities, together with smaller amounts of bromine monoxide (BrO), were enough to destroy ozone at a rate of one to two per cent a day in mid- January at these latitudes 4. The formation of a Northern hemisphere ozone hole in 1992 was averted when a change in the weather in February warmed the Arctic, raising temperatures above the extremely cold levels required for formation of an Arctic ozone hole. Even so, NASA reported a 20% depletion of the ozone layer above the Arctic, as well as ozone losses as high as 1015% over the populated mid- northern latitudes. These findings represented the worst-ever depletion over North America and Europe 5. The latest scientific research has also revealed other mechanisms that exacerbate ozone depletion through reducing chemical reactions that would otherwise convert quantities of reactive chlorine into less reactive, less destructive forms. The AASE II measurements showed that nitrogen oxides, which help convert reactive chlorine and bromine into non-reactive forms, were significantly depleted throughout the lower Arctic stratosphere 6. In addition, the growing presence of dust and pollution particles in the stratosphere (called aerosols) is weakening another crucial component of the ozone layer's defences. As stratospheric aerosols increase, they depress a reaction between methane and chlorine that forms hydrogen chloride. Once more, the result is more reactive chlorine molecules remaining in the stratosphere and able to destroy ozone. One of the most disturbing aspects of past ozone studies has been the consistent underestimation of the rate and extent of ozone loss. Scientists did not predict the formation of the Antarctic ozone hole. They did not expect the extent of mid- latitude depletion now being measured. Nor did they expect the depletion recently measured in the Arctic. Atmospheric scientists are now beginning to warn that current predictions may be overly conservative. UNEP's 1991 Science Assessment concluded that the current quantities of chlorine in the stratosphere, measuring about 3.4 parts per billion by volume (ppbv), would significantly increase to a peak of about 4.1 ppbv, by the year 2000. With these increases in the levels of stratospheric chlorine, the official prediction is that during this decade we can expect double the ozone depletion measured during the 1980s 7. However, Michael Kurylo, NASA's Upper Atmosphere Program Manager, believes that assessment is probably an underestimate because "the atmosphere's ability to keep the ozone losses in check is less than we thought" 8, Dr. Sherwood Rowland, the scientist who first made the link between chlorine compounds and ozone depletion, points out that the rate of ozone loss appears to be accelerating. "The 1980s were considerably worse than the 1970s and it makes it very hard to predict what the future loss will be," Rowland says. The 1991 SORG study sponsored by the UK Government also notes evidence of the increasing rate of ozone loss 9. While there has always been concern about the impacts of the Antarctic ozone hole on the marine food web, until recently it was thought that most highly populated areas of the world were not being affected. Then, in 1991, the UNEP Science Assessment revealed that for the first time, significant ozone loss was occurring in spring and summer in both the Northern and Southern hemispheres and at middle and high latitudes. Large numbers of the world's population live in mid-latitude regions and the fact that ozone depletion is occurring above these populations during spring and summer is of deep concern. The sun's ultraviolet rays are the strongest during these seasons, causing the most harm to humans and other life forms. References to Chapter I 1 Richard A. Kerr, "New Assaults Seen on Earth's Ozone Shield", Science, 14 February 1992. 2 Global Environmental Change Report, "Antarctic Ozone Hits Record Low", 18 October 1991. 3 U.S. NASA press release, "U.S. Study Enhances Concern for Northern Ozone Loss", 30 April 1992. 4 NASA, 1992. 5 Kerr, 1992. 6 Ibid. 7 United Nations Environment Programme (UNEP), Executive Summary, Scientific Assessment of Stratospheric Ozone, 22 October 199l. 8 Kerr, 1992. 9 UK Stratospheric Ozone Review Group (SORG), "Stratospheric Ozone 1991" (London: HMSO,1991). CHAPTER II HCFCS AND HFCS: PART OF THE PROBLEM, NOT PART OF THE SOLUTION 2.1 Overview Widespread use of HCFCs and HFCs could have significant environmental impacts. Both of these chemical groups are potent global warming gases, while HCFCs could greatly exacerbate the ozone crisis, particularly in the short to mid-term 1. Many leading scientists studying ozone depletion have expressed grave concerns about extensive HCFC substitution for CFCs. Dr John Pyle, Chairman of the UK Stratospheric Ozone Review Group (SORG), commented as early as May 1990 that if "substitutes containing chlorine are allowed to grow out of control, we could be back in the same situation in five years time." Drs Susan Solomon and Daniel Albritton of the U.S. National Oceanic and Atmospheric Administration have described in detail the significant short to midterm impacts that HCFCs could have on ozone depletion 2. Unfortunately, such expressions of concern are being largely ignored at present, as industry moves forward with immense capital investments in both HCFCs and HFCs. In 1991, for example, Du Pont announced the construction of a new, $100 million HFC-134a production plant in Texas (U.S.) - one of four such plants which Du Pont will be operating by 1994 3. By the year 2000, Du Pont has estimated that about 40% of current CFC demand will be met by HCFCs and HFCs. The United Nations Environment Programme (UNEP) estimates that by 1997, between 423,000 and 517,000 tonnes of HCFCs alone will be required 4. Furthermore, if CFC user industries including automobile, refrigerator and air conditioner manufacturers become locked into HCFC/HFC paths, worldwide demand could very well exceed even these significant projections. 2.2 Global warming impacts Global Warming Potential (GWP) is a measure of the relative heat-trapping capacity of a particular chemical compared with that of carbon dioxide, the major greenhouse gas. Table 1 (omitted here) shows that over a 20-year timeframe, the main HCFCs are between 300 and 4100 times more potent global warming gases than carbon dioxide. Table 2 (omitted here) lists the GWP of some HFCs, showing that these chemicals are between 500 and 4,700 times more potent global warming gases than carbon dioxide over a 20 year timeframe (see tables overleaf). The Intergovernmental Panel on Climate Change (IPCC) has recently revised upwards its estimate of the impact some HCFCs and HFCs could have on global warming. In its 1990 Report, the IPCC predicted that these chemicals could contribute about 10% to total global warming by the year 2100. In its 1992 Supplement, the IPCC increased the GWPs for some HCFCs and HFCs by 20% to 50%. In the same report, the IPCC warned that "the future production and composition of CFC substitutes (HCFCs and HFCs) could significantly affect the levels of radiative forcing [causing global warming] from these compounds." In short, although factors such as energy efficiency improvements and chemical emission rates also influence overall global warming impact, large production volumes of HCFCs and HFCs could significantly exacerbate the global warming problem. A prudent, precautionary approach demands that such a huge risk should not be taken. 2.3 Chlorine loading impacts Producers of ozone-depleting chemicals (ODCs) have used Ozone Depletion Potential (ODP) values of HCFCs to argue that their impacts on the ozone layer will be minimal. However, ODP is a steady state average measurement calculated over a 100 or 200- year time-frame. ODPs are increasingly being considered relatively poor predictors of the damage which a chemical will do to the ozone layer, particularly in the short and mid-term 5. Although there have been improvements in the models used to define ODPs, they still cannot predict the ozone loss actually observed. Peak levels of stratospheric chlorine loading will occur around the year 2000. The most dangerous time for human health and natural ecosystems (i.e. when maximum levels of ultraviolet radiation will be reaching the surface) is expected to occur at this time, and generally over the next 20 years or so. HCFCs only 'live' in the atmosphere for up to a couple of decades and will therefore do all their damage during this high-risk period (i.e. the short- to mid-term). In a recent study, two highly respected scientists concluded that "long-term ODPs were not appropriate for making short-term (decade-scale) forecasts 1 of HCFC impacts on ozone loss 1." To compensate for this, they calculated 'time-dependent' ODPs. Based on these adjusted values, they concluded that some of the HCFCs proposed as CFC replacements may induce significant ozone depletion in the short to mid-term. For example, the adjusted ODPs (over a ten-year time-frame) for HCFC-22 and HCFC141b are about three or four times higher than their 100-year ODPs 6. The UK SORG scientists have also decisively rejected ODPs as a way of assessing the risks to the ozone layer in the short to mid-term. Instead they recommend using "chlorine loading potentials (CLPs)". These values are based on calculations and observations of how much chlorine actually reaches the lower and upper atmosphere in the short- to mid-term. As Table 3 shows, if chlorine loading potential is used, HCFCs are seen to be significantly more damaging (by a factor of three to five times) compared to their ODP values 7. The 1990 SORG Report stated that substitution of CFCs by HCFCs in other than modest proportion, depending on the lifetime of the particular HCFC used, "could both increase the peak chlorine loading and sustain unprecedented levels of stratospheric chlorine", HCFC production projections by UNEP and industry certainly cannot be considered "modest". The 1991 UNEP Science Assessment predicted that the current chlorine loading level - 3.4 ppbv - will peak around the year 2000 at 4.1 ppbv - about seven times the normal level 8, Perhaps the most important point which was not addressed in the UNEP Report is that any additional input of chlorine to the stratosphere is dangerous. What lies between 3.4 and 4.1 ppbv is about a 20% increase of unexplored territory. It cannot be ruled out, for example, that the additional input of chlorine from HCFCs could contribute to 'non-linear' ozone depletion over the Northern Hemisphere, similar to that which occurred over Antarctica after a threshold level of atmospheric chemicals was reached. 2.4 Breakdown products There are virtually no data available concerning the subsequent degradation of intermediate compounds after HCFCs break down. Estimates of the breakdown of these compounds can be made but both the World Meteorological Organisation and U.K. SORG emphasise that if long-lived products as yet unidentified are formed, these could modify conclusions about the potential for global warming and ozone depletion. There is some evidence that the breakdown products in the atmosphere of both HCFCs and HFCs may include trifluoroacetic acid (TFA), a toxic substance with unknown long-term effects on human health 9. 2.5 Toxicity Even though research on toxicity impacts of HCFCs and HFCs are still under way, companies are moving ahead with production of some of these chemicals. This follows a similar pattern to the way in which CFCs were handled. For example, Du Pont first introduced CFC-113 as a substance "as safe as water". It was later discovered that CFC-113 resulted in the injury and deaths of many Du Pont employees and others 10. There is very little information available on the human health/toxicity hazards of HCFCs. In 1990, the U.S. Environmental Protection Agency (EPA) concluded that all the HCFCs have generally low acute toxicity. However, the EPA results showed that HCFC-123, HCFC-124 and HCFC- 141b all cause depression of the nervous system. Also, HCFC-123, HCFC-141b and HCFC-142a have all been shown to cause mild skin or eye irritation. HCFC-123 has been shown to cause an excess of benign testicular and pancreatic tumours in rats 11, However, HCFC-123, HCFC-124 and HCFC-141b have still not been adequately tested for their carcinogenic potential. HCFC-22 has been tested in rats and mice, and this has shown some evidence of carcinogenicity but the data is inadequate to assess the potential carcinogenicity in humans. Assessment of toxicity of HFCs is at a similar stage as that of HCFCs. They have relatively low acute toxicities. There is generally inadequate data available to assess the impacts on reproductive systems. HFC-152a has been found to cause depression of the nervous system. Table 3 (omitted here) The range of ozone depletion potentials, determined by both one- and two-dimensional models assuming steady-state conditions. The atmospheric lifetimes and chlorine loading potentials of the HCFCs, are also shown (World Meteorological Organisation, 1989) References to Chapter II 1 Susan Solomon and Daniel Albritton, "Time Dependent Ozone Depletion Potentials for Short and Long-term Forecasts", Nature, 7 May 1992; United Kingdom Stratospheric Ozone Review Group (SORG), "Stratospheric Ozone 1991" (London: HMSO, 1991). 2 Solomon and Albritton, 1992. 3 "Du Pont Plans Facility to Make CFC Substitutes", Wall Street Journal, 22 August 1991. 4 United Nations Environment Programme (UNEP), December 1991: Montreal Protocol 1991 Assessment, Report of the Technology and Economic Assessment Panel. 5 Solomon and Albritton, 1992. 6 Ibid. 7 United Kingdom Stratospheric Ozone Review Group (SORG), "Stratospheric Ozone 1990" (London: HMSO, 1990). 8 United Nations Environment Programme (UNEP), 22 October 1991: Executive Summary, "Scientific Assessment of Stratospheric Ozone". 9 Oliver Tickell, "Up in the Air", New Scientist, 20 October 1990. 10 Merritt Wallick, "What Du Pont Didn't Tell Us About Freon-l 13", The Wilmington News Journal, 25 August 1991. 11 United Nations Environment Programme (UNEP), November 1991: 'Environmental Effects of Ozone Depletion: 1991 Update'. CHAPTER III GREENPEACE'S RESPONSE TO THE OZONE CRISIS 3.1 The precautionary approach It has been known for many years that the impacts of chlorine- based CFCs and related gases are causing increasing harm to human beings and other life forms on Earth, and that computer models are inadequate for accurately predicting future ozone loss. Yet, in formulating ozone policy, decision-makers have consistently allowed more short-sighted concerns to come before human health and the needs of the environment. Greenpeace has long been advocating a different type of approach - a 'precautionary approach' toward protecting the ozone layer. It is based on the 'precautionary principle' which, in its simplest form, can best be summed up as follows: "A substance should not be emitted if it may cause harm to human health and the environment." This principle holds particular significance when a global life support system such as the ozone layer is demonstrably being destroyed. Furthermore, the evidence of the harmful impacts of ODCs is so indisputable and overwhelming, and the stakes are so high that simple common sense alone should be the basis of an immediate ban, before the precautionary principle is even considered. It is important to note that the international community, and not only Greenpeace, has begun to adopt the precautionary approach as accepted environmental policy. This demonstrates a move toward policies based on prevention of pollution. 3.2 Response measures Greenpeace believes that an effective response to the ozone crisis must include the following steps: . An immediate 100% production ban on all ozone-depleting chemicals (ODCs) and HFCs. Banned ODCs must include: CFCs, HCFCs, HBFCs, halons, carbon tetrachloride, and methyl chloroform. . Reduction of emissions through mandatory recapture of ODCs at various stages of a product's lifetime, such as during servicing and disposal. Also, other modified procedures for eliminating emissions should be made mandatory (e.g. no longer releasing halons during firefighting testing and training exercises). . Active research, development, and promotion of alternatives by governments and industry. This should include a wide range of economic support mechanisms, as well as revision of the terms of reference of the Montreal Protocol Multilateral Fund to more appropriately reflect the imperative of promoting safer alternatives. . Full public disclosure by industry and governments of information on production, consumption, import and export of ODCs. . Safe storage of ODCs until environmentally appropriate destruction technologies have been identified. . Special arrangements for developing-country assistance. For example, technology transfer should be significantly increased, as should the size of the Montreal Protocol's Multilateral Fund. . Action by individuals to eliminate, as much as possible, their use of products containing or manufactured with ODCs. PART TWO: SURVEY OF ALTERNATIVES The following is a preliminary survey of alternatives in each of the five major industry use sectors: refrigeration and cooling, solvents, aerosols, foams and firefighting. Summaries and conclusions are included in each chapter. CHAPTER IV REFRIGERATION AND COOLING 4.1 Summary CFCs have been used for many decades as heat exchange agents in refrigeration, air conditioning and heat pump applications. In 1990, 260,000 tonnes of CFCs were used in these applications worldwide 1. There is a wide range of alternative refrigeration technologies. These include different types of refrigerants and refrigeration cycles. Some, such as ammonia-based vapour compression (v-c) and absorption systems, water-based evaporative cooling systems and hydrocarbon-based v-c systems are already in wide use. Others such as helium-based Stirling cycle systems and zeolite- based adsorption systems are either beginning to enter commercial markets or will in the near term. This is rather remarkable in itself given the inadequate research and development which these technologies have received. Many of these commercial timetables are more dependent on sufficient funding levels and political decisions than technical obstacles. Also, it is important to note that many of the alternative refrigeration systems are competitive with, or even superior to, conventional v-c systems using CFCs, HCFC-22, or HFC-134a, in terms of costs and efficiency. When considering alternatives to CFC use, questions need to be raised about the necessity of some refrigeration and cooling applications. Some, for example, can be replaced by simpler, low-technology alternatives such as better ventilation systems and window coatings for automobiles. Some of the total refrigeration and air conditioning 'capacity' could be eliminated by simply using fewer and smaller units. 4.2 Statement of the problem: current uses of ozone-depleting chemicals in the refrigeration and cooling sector Historically, food preservation and transport were the original needs that led to the development of the refrigeration industry. In 1990, 260,000 tonnes of CFCs were used worldwide in the refrigeration and cooling sector. Of that total, 207,000 tonnes were used in the air conditioning sector to cool buildings and automobiles. A further 19,000 tonnes (almost 10% of the total) were used in refrigeration systems, with the greatest use in the domestic sector (9,500 tonnes) followed by industrial (4,500 tonnes) and commercial (4,500 tonnes) applications 2, CFCs are also used to a lesser extent in heat pumps and other industrial processes. 4.3 The alternatives 4.3.1 General considerations There are a number of refrigeration cycles which are currently in use or being researched. These cycles can use a variety of alternative refrigerants. The efficiency of the system depends upon the system design, which needs to be optimised for a particular refrigerant, and on the properties of that refrigerant. (a) Vapour compression The most common refrigeration 'cycle' is known as vapour compression (v-c) and is found in most domestic, retail and industrial applications. This system uses electrical energy to continually pump a refrigerant (traditionally CFCs) between its liquid and gaseous phases, thus causing a cooling effect. Several alternative refrigerants for v-c systems can be used, including water, ammonia and hydrocarbons. Ammonia and propane- based v-c systems have already been in use for several decades. (b) Absorption Absorption cooling cycles work with a pair of refrigerant chemicals. In these two component systems, one of the chemicals is dissolved in the other. Cooling is produced by driving one of the chemicals out of the solution by the application of heat and then reabsorbing it into the solution. The two most common refrigerant pairs used in the absorption cycle are ammonia/water (ammonia systems), in which ammonia serves as the refrigerant and water/lithium bromide (lithium bromide systems), in which water serves as the refrigerant. Absorption cycle machines have been used extensively for several decades for food preservation, industrial processes, cold storage and other applications 3. Relatively little technological development has occurred in the past few decades and specialised applications are now the main use of these systems. Most absorption machines are large and designed to use waste heat from another source 4. (c) Adsorption The adsorption cycle is similar to the absorption cycle except that the refrigerant attaches to, and detaches from, a solid medium. Heat drives the refrigerant off the solid medium and cooling occurs when it returns to the solid medium by adsorption. Zeolite/water can be used as a refrigerant pair and solar energy, natural gas and waste heat are among the possible heat sources for this system. (d) Evaporative cooling Cooling by evaporation involves- the natural cooling effect of water evaporating into air. This process removes heat from liquid water in order for some of the water to evaporate into the air. The system has a long history of use as an inexpensive cooling system. Today, air conditioning and general cooling to remove waste heat, such as in cooling towers, are the main uses for this technology. Liquid desiccant cooling is a modification of evaporative cooling which allows the use of the technology in high humidity areas. In these systems, a liquid first absorbs the water out of the air and the dried air then enters an evaporation cooler. Since the air is dry, the cooler works at high efficiencies. (e) Stirling The Stirling refrigeration cycle continuously expands (heats) and compresses (cools) a fixed mass of gas without changing physical state. These systems are highly efficient and can be used over a wider range of temperatures than other systems. Helium is the most promising refrigerant being tested. (f) Other cooling technologies There are several other lesser-known technologies being used or researched. One rather novel technique which is currently being used to cool highway freight trailers is gas expansion. It involves spraying a pre-cooled liquid, such as liquid carbon dioxide or nitrogen, into the refrigerated area which causes the liquid to evaporate and hence cool 5. Another promising technology being researched by the Los Alamos National Laboratory (U.S.) is known as thermo-acoustic cooling. It uses sound waves to produce cooled gases and has several advantages over conventional systems 6. 4.3.2 Defining what is "essential" Questions must be raised as to the extent to which refrigeration and air conditioning are used today. Some of the uses, such as automobile air conditioning in certain climates, could be considered unnecessary and non-essential. Furthermore, some of the total refrigeration and air conditioning capacity could be reduced by simply using fewer and smaller. When planning new buildings, optimum building design, air circulation and ventilation and reflective window films and coatings should all be actively investigated as alternatives to air conditioning capacity. In the area of food transport, increased local food production would reduce the need for long distance refrigerated food storage. Such measures would have the added advantage of energy savings. 4.3.3 Safest known alternatives (a) Water (v-c cycle and evaporative cooling) A German company is using water as a refrigerant in a modified v-c cycle. The water is under vacuum since it can only function as a refrigerant below atmospheric pressure. The system produces chilled water without an intermediate heat exchanger which enhances the efficiency of the system 7. This system is limited to temperatures above freezing. An add-on system employing mixtures of ice and water is also being used so that cooling is produced both by melting and evaporation. Systems have to be significantly larger than equal capacity CFC systems because of the large volume of water required. Current applications already include district heating (heat pumps) and mine tunnel cooling plants 8. Evaporative cooling, which works best in dry, hot climates, is today being developed for a variety of applications. Over 70 U.S. companies manufacture evaporative air conditioners for residential, automotive, commercial and industrial applications. For example, over 400 public transit buses in the U.S. have evaporative-cooling air conditioning systems and a prototype unit is being tested by a U.S. automobile company 9. Liquid desiccant cooling allows the use of evaporative cooling in high humidity areas. A group of companies in the U.S., U.K. and Saudi Arabia are developing a system using lithium bromide. The system has achieved significant energy savings over conventional air conditioning systems 10. (b) Zeolite/water (adsorption cycle) Zeolite is a naturally occurring mineral that is hygroscopic, i.e. it attracts water. Tests in the U.S. on a heat pump using zeolite, with natural gas as the heat source, produced favourable results. In Germany this technology is being researched for applications such as mobile coolers, domestic refrigeration and automotive air conditioning 11. A German auto manufacturer is planning to install zeolite/ water air conditioning units on production cars as early as 1993 12. (c) Helium (stirling cycle) Helium is being tested in Stirling cycle systems. These systems are likely to be on the market in the near to mid-term. Small prototype Stirling cycle refrigerators have been successfully tested by a major European refrigerator manufacturer. Field testing is now planned for a full size domestic refrigerator 13. One U.S. company has already completed prototype tests on a cooler for domestic refrigeration, again with favourable results. Several other U.S. companies are also conducting research on Stirling cycle machines, looking particularly at domestic refrigeration applications. Preliminary performance testing has yielded very promising results 14,15. One company is using a gas-fired Stirling heat engine (which is more efficient than the internal combustion engine) to power a domestic refrigerator. Predictions are for an 81% increase in efficiency over conventional v-c cycle machines 16. It should be noted that the limited supply of helium could influence the scale of Stirling cycle machine use. (d) Liquid carbon dioxide and nitrogen (gas expansion) A U.S. company has developed a system that cools highway freight trailers using liquid carbon dioxide or liquid nitrogen 17. The system consists of a storage container mounted under the trailer, a propane tank, a heat exchanger and controls. The storage tank contains one of the liquid gases, depending upon the application. A small amount of propane helps expand the liquid gases in the heat exchanger. A test is being run to evaluate the effectiveness and efficiency of the units and preliminary data suggests that the lighter systems could lead to fuel savings and much greater efficiency 18. 4.3.4 Other alternatives (a) Ammonia (v-c cycle) Ammonia has been in use as a refrigerant for many decades, even well before the advent of CFCs. Its superior efficiency and heat transfer properties relative to CFCs has made it the chemical of choice in many large chiller installations using v-c cycles. Research has shown ammonia to be superior to HCFC-22 in terms of efficiency (at most temperatures), availability and cost l9. 20, In other comparison studies, ammonia has been shown to be technically superior to HFC-134a and typically about 4% of the cost 21. In the past, ammonia was used in domestic refrigerators. The use of small volumes (for example, about 100g) and hermetically- sealed units in appropriate corrosion-free materials should present few problems for their re-establishment in this application. A U.K. Government report noted that "there is no technical reason why ammonia cannot be used again in domestic refrigeration equipment" 22. Ammonia systems are widely used today in the food storage, processing and chemicals industries. In the U.K., a large supermarket chain uses ammonia in its two main cold stores 23. In the U.S., 81% of refrigerated warehouses operate on ammonia systems 24. In Germany, nearly two-thirds of cold storage and food processing systems use ammonia, compared with only 7% using CFCs. A similar trend is seen in the Nordic countries, Eastern Europe, and most developing countries 25. Many companies around the world use large ammonia water-chiller machines. The current development trend is towards smaller machines which are being sold and installed as entire units, as opposed to larger machines which require on-site assembly. A company in Sweden manufactures smaller, packaged water-chiller units which cool water in a circulation loop using plate heat exchangers. The chilled water serves air conditioning, food storage and processing, and industrial applications. The volume of ammonia required is much less than the more traditional heat exchanger systems 26. A U.S. manufacturer produces similar packaged systems that also supply chilled water for a variety of air conditioning and refrigeration applications 27. A German company has developed a hermetically sealed ammonia refrigeration system. The innovative parts of this system are an enclosure that seals the ammonia system from the surroundings and an absorption system that can absorb any ammonia which escapes into the enclosure 28. Another German company is developing ammonia systems which could supply supermarkets with all their cooling requirements, including frozen food storage, cool cabinets and counters, cooled meat cutting rooms and general air conditioning 29. Ammonia is flammable and toxic at low concentrations, but is not persistent in the environment. Thorough care needs to be taken with the installation and maintenance of ammonia-based equipment 30. (b) Hydrocarbons (v-c cycle) Although not well known to the general public, hydrocarbons are well established as refrigerants and were, like ammonia, used extensively in domestic and small commercial applications in the past 31. Hydrocarbons can, in some cases, be used as 'dropin' substitutes to CFCs in existing conventional v-c machines. They have excellent refrigerant properties with thermodynamic efficiencies equal to or above CFCs 32. Operating temperatures are also comparable. Other advantages of hydrocarbons are their ready availability worldwide and cost - roughly 50 times less than compounds such as HFC-134a, which is being actively promoted as a CFC refrigerant substitute 33. These factors make hydrocarbon-based refrigeration/cooling options particularly attractive for developing countries. New hydrocarbon applications are being increasingly used and researched. Hydrocarbons are now used as refrigerants at industrial sites around the world where the facility is already set up to meet the standards concerning use of flammable substances 34. A German pharmaceutical company is now using a 45kW industrial cooler which uses a propane/ butane refrigerant charge 35. Scientists from the South Bank Polytechnic in the U.K. have retrofitted a domestic refrigerator with propane and have produced positive performance results even without design changes 36. The system performance is likely to be improved if it is optimised for propane use. A domestic refrigerator, using a propane/butane mixture as a refrigerant, produced by one of Germany's leading refrigerator manufacturers will be on the market by March 1993. The refrigerator will sell for less than 700 DM (U.S. $490), the equivalent of conventional CFC refrigerators, and is already slightly more energy efficient than conventional models using CFC-12 and considerably more efficient than models using HFC- 134a, with the likelihood of further efficiency improvements 37. 38. A U.S. company has tested an air conditioning unit with propane as the refrigerant and the test performance results are highly promising 39. Flammability should not present a problem because of the small refrigerant charge used. The use of hydrocarbons in small-scale applications ceased in the 1930s as a result of concerns about flammability and the invention of CFCs. However, even then, despite poorer technical safeguards and relatively high refrigerant volumes, the safety record was excellent 40141. Based on the results of extensive testing, flammability should not present major problems for domestic or other small-scale applications today 42. One main reason is that given current technology, only about 20 g of refrigerant is necessary: about the same volume found in cigarette lighter refill containers 43, 44. The U.K. Institute of Refrigeration states that "it would appear to be sensible in the short term to use propane as the refrigerant for domestic refrigerators" 45. (c) Ammonia/water (absorption cycle) In ammonia/water absorption systems, the ammonia acts as the refrigerant. These systems can operate at temperatures well below freezing. Absorption systems are currently used in domestic and industrial refrigeration, as well as in air conditioning applications 46. If primary heat or waste heat from a combined heat and power unit is used, efficiency is comparable to that of a conventional v-c system 47. Ammonia absorption refrigerators are currently used in applications such as mobile homes, hotel room mini-bars and hospitals. In Germany, for example, they comprise about 5% of the household market 48, There are some smaller machines being used in the air conditioning industry and some are also used as heat pumps. Absorption refrigerators and refrigerator/freezers are marketed in the U.K. by one of the largest refrigerator manufacturers, in sizes varying from 25 to 170 litres 49. Another company in the U.K. currently markets residential absorption air conditioners and combination heat pumps 50. Testing has shown that, during the heating season, the absorption heat pump had a lower energy demand than a comparable electric heat pump 51. Absorption systems are being further developed. A gas-fired heat pump system has been shown in tests to be more efficient than a conventional gas-fired heater. Although the system tested was for residential use with only a 3kW heating capacity, the concept is applicable to much larger units and for hot water as well 52. Ammonia heater/chiller appliances have been developed by a U.K. company and British Gas for air conditioning in buildings. Ammonia absorption chillers are used widely today in air conditioning in banks, restaurants, office buildings and many other locations 53. Safety concerns with ammonia absorption systems can be minimised through engineering techniques and use of small refrigerant charges. (d) Lithium bromide/water (absorption cycle) Water can be used as a refrigerant paired with lithium bromide in absorption systems which must be operated above freezing temperatures. Air conditioning and water chillers have been the major applications. There are many manufacturers developing such systems worldwide 54, 55. One of the largest manufacturers of refrigeration and cooling equipment in the U.S. markets these systems to cool process water for industrial applications and for air conditioning in hospitals 56. Research is under way to examine a 'combined-cycle' system consisting of a lithium bromide absorption machine with a compressor integrated into the water vapour loop and driven by exhaust heat 57. 4.4 Conclusion Alternatives exist for all major applications in the refrigeration and cooling sector. Expanded use of alternative technologies that have been in existence for some time, such as propane and ammonia based vapour-compression systems and evaporative cooling, is being re-examined. In recent years, even with the limited funding available, there have been some important advances in new technologies. For example, helium- based Stirling cycle systems hold great promise in the short- to mid-term. Other technologies such as adsorption systems using zeolite and water, and absorption systems based on ammonia and water are commercially available and becoming more widely used. The primary obstacles to a complete transition to these alternatives are political. The decisions to produce commercially or expand the marketing of these systems are blocked much less by technical barriers (e.g. performance and efficiency) than by political and economic ones. Once the political and funding decisions were made, the complete transition to alternatives would be rapid. References to Chapter IV 1 United Nations Environment Programme (UNEP), December 1991: Montreal Protocol 1991 Assessment, Report of the Refrigeration, Air Conditioning, and Heat Pumps Technical Options Committee. 2 Ibid. 3 Roger Thevenot, 'A History of Refrigeration throughout the World', [International Institute of Refrigeration, Paris: 1981]. 4 Brian Streatfield, "The Absorption Option", Refrigeration and Air Conditioning, July 1991. 5 General Cryogenics (U.S.) Product Data and Business Plan, 1992. 6 Malcolm W Browne, "Cooling with Sound: An Effort to Save the Ozone Shield", The New York Times, 11 March 1992. 7 Paul Joachim, "Water as a Refrigerant and Coolant", paper presented to the Alternatives to CFCs and Halons International Conference, Berlin. February 1992. 8 Ibid. 9 Climatran Corporation (U.S.), Product Data and Summary, 1991. 10 Albers Corporation (U.S.), Product Data and Summary, February 1992. 11 Proceedings from Alternatives to CFCs and Halons International Conference, Berlin, February 1992. 12 W. Schwartz, Oekologische Briefe (Frankfurt, Germany), 26 February 1992: personal communication. 13 Matteo Bellomo, Electrolux, Torino, Italy, 28 February 1992: personal communication. 14 D.M. Berchowitz and R. Unger, "Experimental Performance of a Free-Piston Stirling Cycle Cooler for Non-CFC Domestic Refrigeration Applications", XVIII International Congress of Refrigeration, Montreal, Quebec, August 1991. 15 D.M. Berchowitz and J. Shonder, "Evaluation and Performance of a Natural Gas Fired Duplex Stirling for Domestic Refrigeration Applications", XVIII International Congress of Refrigeration, Montreal, Quebec, August 1991. 16 Dr Roelf J.Meijer, Stirling Thermal Motors, 25 February 1992: personal communication. 17 General Cryogenics, 1992. 18 Ibid. 19 W.F Stoecker, Growing Opportunities for Ammonia Refrigeration, In CFCs: Time of Transition, Am. Soc. of Heating, Refrigeration and Air Conditioning Engineers. Atlanta, 1989. 20 Umvelt Bundes Amt., Responsibility Means Doing Without - How to Rescue the Ozone Layer ( The German Federal Environment Agency: 1989). 21 Stoecker, 1989. 22 DTI, London, 1990: CFCs and Halons: Alternatives and the Scope for Recovery, Recycling and Destruction. 23 "Taking the High Road to Distribution", Air Conditioning and Refrigeration News, February 1991. 24 UNEP, Synthesis of the Reports of the Ozone Scientific Assessment Panel, and Technology and Economic Assessment Panel. Presented to the Open-Ended Working Group of the Parties to the Montreal Protocol, Sixth Meeting, Geneva, 6-15 April 1992. 25 Ibid. 26 The Electrolux Guide to Refrigeration on the Road, Sweden 1991. 27 Thermatech, Catalog 91-01, Packaged Ammonia Systems Eliminate Field Construction Problems, 1991. 28 Aerotech, Ammonia in Supermarkets, January 1992. 29 H.G. Schmidt, "Ammonia in Supermarkets", Presented to the International Conference on Alternatives to CFCs and Halons, Berlin, February 1992. 30 D.A Althouse and C.H. Braceliano, Modern Refrigeration and Air Conditioning (Goodheart Willcox, Illinois: 1992). 31 H.T. Haukas, "Halogen Free Hydrocarbons as Refrigerants", presented to the International Conference on Alternatives to CFCs and Halons, Berlin, February 1992. 32 Ibid. 33 R.W. James and J.F. Missenden, "The Use of Propane in Domestic Refrigerators". Int. Journal of Refrigerations vol. 15, 1992. 34 Ibid. 35 Wolfgang Lohbeck, Greenpeace Germany: personal communication, April 1992. 36 James and Missenden, 1992. 37 Taryn Torra, "German Industry Freezes Out Green Fridge", 'New Scientist', 22 Aug. 1992. 38 According to officials at DKK Scharfenstein (Germany), September 1992. 39 David E. Treadwell, Application of Propane (R290) to a Single Packaged Unitary Air-Conditioning Product, International Conference on Alternatives to CFCs and Halons, Berlin, 1991. 40 Haukas, 1992. 41 James and Missenden, 1992. 42 Ibid. 43 Ibid. 44 Haukas, 1992. 45 Institute of Refrigeration, London, 1991: Environmental Effects of Refrigerants. 46 Althouse and Braceliano, 1992. 47 German Federal Environment Agency, 1989. 48 Ibid. 49 Electrolux, 1991. 50 Elstree Air Conditioning product brochure, Gas Absorption Chiller, Heater, 1992. 51 N.G Moore and N.M. Gibson, Field Study of Gas and Electric Combined Chilling and Heating Appliances, British Gas, 1989. 52 H. Stierlin and J.R. Ferguson, Diffusion Absorption Heat Pump (DAHP), Absorption Heat Pumps - proceedings of a workshop held in London, Commission of the European Communities, Directorate General, Research, Science and Development, April 1988. 53 Heating and Ventilation Review, August 1990: "CFC Free with Gas". 54 G.Alefeld and F. Ziegler, Advanced Heat Pump and Air Conditioning Cycles for the Working Pair Water/LiBr: Domestic and Commercial Applications, Paper No. Hl-85-41 No. 2, ASHRAE, 1985. 55 R.C DeVault, Advanced Absorption Technology Development in the United States, Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S., 1990. 56 B. Streatfield, "The Absorption Option", Refrigeration and Air Conditioning, July 1991. 57 Ibid. CHAPTER V SOLVENTS 5.1 Summary CFC-113 and methyl chloroform have been used extensively as solvent cleaning agents in electronics, metal and precision cleaning processes, as well as in other minor uses such as dry cleaning. Alternatives are now in wide-scale commercial use for virtually every application where CFC-113 or methyl chloroform have been employed. These alternatives include processes which eliminate the need for cleaning by using 'no clean' fluxes and controlled atmospheric soldering; aqueous and semi-aqueous cleaning methods and specialised cleaning methods (e.g. ice particle sprays and pressurised gases such as air and nitrogen). Many of the world's largest computer companies have already completely phased out the use of ozone-depleting solvents and others are planning to do so in the 1992/1993 period. 5.2 Statement of the problem: current uses of ozone-depleting chemicals (ODCs) in the solvents sector 5.2.1 General considerations The major applications of CFC-113 and methyl chloroform as solvents are in electronics, metal and precision cleaning processes. Dry cleaning of fabrics is another more minor use. The United Nations Environment Programme (UNEP) Solvents, Adhesives, and Coatings Technical Options Committee (the 'Solvents Committee') reported in its 1991 Assessment that worldwide consumption in 1990 was approximately 178,000 tonnes of CFC-113 and 726,000 tonnes of methyl chloroform. CFC-113 is used primarily in electronics cleaning, while methyl chloroform is used primarily in metal cleaning applications. They have been employed because of their successful cleaning characteristics, relatively low price and perceived environmental safety. The Solvents Committee estimates that "50% of current worldwide CFC-113 use results from U.S. military specifications". For many years, the U.S. Department of Defense has specified that circuit boards and other electronic components be cleaned with CFC-113. Although this was not a performance-based standard, many electronics producers decided to use CFC-113 for all cleaning requirements to help guarantee sales to the large military market. Even today, many companies use military specifications - which are not based on technical necessity or lack of other alternatives - as default specifications 1. Since the initial regulation of CFC-113 under the Montreal Protocol, there has been a worldwide shift towards methyl chloroform in many end-uses, as this was not a regulated compound under the Montreal Protocol until 1990 2. 5.2.2 Electronics cleaning The bulk of CFC-113 and methyl chloroform use as solvents is in the area of electronics cleaning. CFC-113 is employed primarily in two cleaning processes in the electronics industry: defluxing and degreasing. A flux is a material applied to the surface of an electronic component prior to soldering which improves its solderability. Defluxing removes the flux residue after soldering through the action of the solvent cleaner, traditionally CFC-113 or methyl chloroform. Degreasing is the process which removes contaminants such as grease, oil, fingerprints and dust from electronics or metal parts. These can build up during transport, storage and production. Examples of components cleaned with CFC-113 in electronics manufacturing include printed circuit boards, disk drives, telecommunications hardware and cathode ray tubes (for computer screens and televisions). Major uses of methyl chloroform include cleaning of printed circuit boards, transistor packages and their leads. 5.2.3 Metal cleaning Cleaning is an important process in the production, maintenance and repair of many fabricated metal parts and components. It is performed to remove contaminants from raw materials and parts prior to operations such as machining, painting, electroplating and packaging. Products which often require metal cleaning in their manufacture include furniture and fixtures, primary metals, fabricated metal products, machinery and transportation equipment. Methyl chloroform has been the primary solvent used for metal cleaning applications; CFC-113 has been used to a lesser degree. An estimated 65% of the world's annual production of methyl chloroform is used in metal cleaning 3. Carbon tetrachloride is also used in some developing countries for metal cleaning. 5.2.4 Precision cleaning Precision cleaning spans a number of different industries, including electronics, medical equipment, military systems and aerospace technologies. Precision cleaning is characterised by the extremely high cleanliness standards required, sensitive compatibilities of materials, physical characteristics such as geometry and porosity and the high costs of the components cleaned. Precision cleaning processes remove both particulate and non-particulate contamination. CFC-113 and methyl chloroform have both been used in precision cleaning applications. Products which require precision cleaning include computer disk drives, precision instruments, optical components and hydraulic control systems. 5.2.5 Other uses Dry cleaning involves the use of chlorinated solvents that do not distort fibres, to clean fabrics that cannot be cleaned by water. CFC-113 is used only in some countries and the Solvents Committee estimates that 4% of dry cleaning machines worldwide employ methyl chloroform 4. 5.3 The alternatives 5.3.1 General considerations Manufacturers worldwide are making rapid transitions away from CFC-113 and methyl chloroform. For example, two U.S. companies, both large manufacturers of printed circuit boards and formerly large consumers of CFC-113, have completely eliminated all of their CFC-113 use by switching to no-clean processes and aqueous cleaning 5,6. One of the largest computer companies, a major CFC-113 user in the past, predicts that all of its electronics and circuit board manufacturing plants worldwide will be CFC- free by 1992 7. 5.3.2 Defining what is "essential" There are no essential uses of ODCs in the solvents sector. One area which has been cited by some as problematic in terms of finding adequate alternatives is dry cleaning of fabrics. However, much of the fabric currently labelled as needing dry cleaning could be cleaned using a gentle wash cycle on a conventional washing machine. Moreover, clothes can be cleaned in more traditional ways such as spot cleaning, brushing and steaming. New, safer cleaning methods are being developed at the industrial level. For example, a U.K. company has several shops in the U.K. and U.S. using a three-step process which: (i) removes the moisture from clothes using hot air; (ii) removes spots with a small vacuum cleaner; and (iii) replaces the moisture in clothes when pressed 8. 5.3.3 Safest known alternatives (a) Low solids fluxes - 'no-clean technology' A number of technologies are now being widely used which eliminate the cleaning stage in electronics manufacturing. The use of low solids fluxes which contain 1 - 10% solids are the key to most no-clean systems. Low solids fluxes are composed primarily of liquids such as isopropyl alcohol. Because these fluxes contain less rosin or other solids, it is not necessary to use CFC-113 or methyl chloroform to remove them (deflux) after soldering. It is now also possible to employ a no-clean system with certain mildly activated rosin fluxes. After the flux is applied, electronics boards are heated and sent to a molten-wave solderer, where almost all of the flux simply boils off. Tests have shown that the remaining residue will not affect the performance of the electronics components over their 40 year lifetime. A large U.S. defense contractor recently announced the development of a citric acid flux called HF1189 that is solvent- free, water-based and water-soluble and thus eliminates the need for CFC defluxing. The company is heralding its citrus solution as a "breakthrough" for defense electronics manufacturers who must meet U.S. Department of Defense requirements 9. Furthermore, an international manufacturer of microcomputer components has also eliminated all of its ODCs use by switching to water-soluble solder and no-clean systems. A major North American producer of printed circuit boards for the telecommunications industry, and formerly a large consumer of CFC-113, has eliminated all of its CFC-113 use by switching to the use of low-solids fluxes. As a representative of the company has explained, "The technology questions to get out of the use of CFC-113 are answered. It's a done deal." The company went from using thousands of kilogrammes of CFC-113 in 1986, to a complete worldwide elimination of all uses in 1992 10. Another major North American telecommunications company estimates that their switch to noclean methods will prevent 9,000 tonnes of CFCs from being emitted and save $50 million in costs over the next 8 years 11. One Swedish company and several leading international computer companies have also eliminated CFC-113 use throughout their operations by switching primarily to similar no-clean technology. Initially there were concerns that no-clean technology was appropriate only for large multinational electronics companies. However, small companies are now accessing and using this technology as well. A survey of 47 printed circuit board manufacturers in Japan in 1990 found 30 firms were using a noclean alternative. One company has developed a noclean manufacturing system which not only eliminates the need for CFC defluxing, but also reduces by 80% the amount of flux material used 12, The change to no-clean processes is also happening in other parts of Asia. For example, a survey of 29 Taiwanese electronics firms showed twelve were already using no-clean processes 13. (b) Nitrogen - controlled atmosphere soldering Controlled atmosphere soldering is another means of eliminating the CFC-113 cleaning stage in the manufacturing process. One such method, inert atmosphere soldering, sprays an inert gas such as nitrogen across the molten solder and above the soldering area to displace air. Minimizing the amount of oxygen present reduces the formation of oxides on the component surface and the molten solder. As oxides are no longer formed at normal rates, fluxes are reduced or not required at all and CFC-113 cleaning is eliminated. Electronics companies in Europe and North America use controlled atmosphere processes to wave solder both through hole and surface mount components. A commercial-scale inert atmosphere soldering process that will eliminate the need for cleaning with CFCs is being developed in the U.S. In the process, a mild solution of adipic acid is used to remove oxides from metal surfaces before they are soldered in an inert atmosphere. Results from testing have been positive 14. (c) Deionised water - aqueous cleaning Although aqueous cleaning systems have been used for many years in electronics and metal cleaning operations, recent advances have allowed for their use in cleaning of surface mount technology electronics, as well as in other areas. Deionised water, a very effective solvent, is used to remove ionic contaminants, water-soluble fluxes and other contaminants. In some cases, additives e.g. saponifiers (chemicals which react with organic fatty acids to form water-soluble soaps) are necessary to improve the performance of the cleaner by removing nonpolar substances such as oil and rosin flux. Aqueous cleaning involves a system of processes for cleaning, rinsing, drying and recycling. It can be enhanced through different delivery equipment such as heated immersion systems, ultrasonic cleaning systems and spray cleaners. Rinsing can be accomplished with tap water, a water/alcohol blend or with other additives, depending on the level of cleanliness required. One U.S. company has been using aqueous cleaning systems in the production of printed circuit board assemblies since 1974 15. In the last several years, they have perfected and patented a new aqueous cleaning process for fine pitch surface mount components. This process, called "MicroDroplet" aqueous cleaning, utilises water droplet size and angle of impingement to effectively clean rigid leaded surface mount components and can exceed cleanliness achieved using CFC-113 systems. The main environmental drawback with aqueous systems concerns the disposal of the resultant waste water. (d) Semi-aqueous cleaning without hydrocarbons Semi-aqueous cleaning systems are effective in a range of electronics applications, including difficult surface mount technology for printed circuit boards. These systems use an agent to dissolve contaminants, followed by a water rinse to remove the solvent residue. They are effective in removing polar and non-polar contaminants, do not leave "white residue" on parts and their performance can be enhanced through blending with other agents. Some of the safer semi-aqueous cleaners are vegetable oils (which are being used for cleaning printing ink) and fatty acids. (e) Alcohol cleaning without perfluorocarbon additives Alcohols such as ethanol and isopropanol, and glycol ethers have been used effectively as cleaners in printed circuit board and precision component manufacture. They are particularly effective in removing rosin and polar activators used in fluxes. Particulate and organic contamination can be removed more completely than with CFC-113 and much smaller quantities are required (e.g. 50% less isopropanol by volume compared to CFC-113) 16, Care must be exercised with alcohols due to their flammability. (f) Ice Two Japanese companies have developed a novel method for cleaning printed circuit boards that completely eliminates the need for ozone-depleting solvents. Their ice scrubber cleaning apparatus removes sub-micron contaminants from semi-conductor wafers using a process in which ice particles are sprayed at the dirty surface. Using tiny ice particles (ranging from 0.1 to 300 micrometers in diameter) and controlling the hardness and size of the particles, as well as the pressure and angle of the spray, the cleaning system can remove contaminants very effectively 17. (g) Pressurised gases Pressurised gases such as air, rare gases, carbon dioxide and nitrogen can be used as cleaning agents to remove particulate contamination. These gases have low toxicity, are non-flammable and relatively inexpensive. Pressurised gases can replace CFC- 113 and methyl chloroform in precision cleaning operations such as removing metal dusts during manufacturing 18, Supercritical fluids are a category of pressurized gases that can be employed in special precision cleaning operations. Supercritical gas extraction utilizes the solvent abilities of certain fluids at high temperatures and pressures. This is particularly effective for removing contaminants of low polarity and medium molecular weight. Supercritical fluid cleaning is a very flexible process and has a short cleaning time. This process can be used, for example, to clean high voltage cables for spacecraft, optical benches for lasers and transformers for radar equipment 19. (h) Plasma Plasma cleaning utilises electrically charged gas containing ionised atoms, electrons, highly reactive free radicals and electrically neutral species to remove contaminants from the surface of precision parts. The cleaning occurs when the ions and electrons in the plasma are energised and react with contaminants such as carbon monoxide, carbon dioxide and water vapour. The contaminants are then removed by the flow of the process gas. (i) Ultraviolet (UV) light and ozone UV light/ozone cleaning is a simple process involving the exposure of a contaminated surface to UV light in the presence of ozone (03). Cleaning occurs as a result of the reaction between the contaminant molecules and the UV light, creating volatile molecules which remove the surface contamination. This process has been used effectively to remove thin organic films that build up on glass, quartz, ceramics, metals, silicon, gallium arsenide and other materials. 5.3.4 Other alternatives (a) Hydrocarbons - semi-aqueous cleaning Electronics companies worldwide are now introducing hydrocarbon solvents for use in semi-aqueous cleaning systems. The compounds being used are all environmentally problematic and include terpenes (e.g. d-limonene), petroleum hydrocarbons, N-methyl pyrrolidone and dibasic esters. The system usually employs a water rinse to remove the solvent residue. A surfactant (or wetting agent) is often added to improve wetting, emulsification and rinsing properties. Semi-aqueous cleaning systems usually have a drying stage to remove excess water from the parts and then a wastewater disposal process. The wastewater is a hazardous waste. (b) Alcohol cleaning with perfluorocarbon additives Because alcohols used in semi-aqueous cleaning are much more flammable than other solvent agents, they are often blended with perfluorocarbons (PFCs) to decrease the flammability. PFCs, however, have a strong global warming potential. 5.4 Conclusion There is no ODC use in the solvents sector which cannot be replaced today by commercially available alternatives. Many of these have proved to be more efficient and cost-effective than CFC-113 and methyl chloroform cleaning processes. In just the past few years, there has been a dramatic worldwide shift by the electronics and other industries away from ozone- depleting solvent cleaning processes toward the use of a wide range of alternatives. These include: process changes which eliminate cleaning stages; aqueous and semi-aqueous cleaning methods; and specialised cleaning processes using ice particles, pressurised gases and other methods. References to Chapter V 1 United Nations Environment Programme (UNEP), December 1991: Montreal Protocol 1991 Assessment, Report of the Solvents, Coatings and Adhesives Technical Options Committee. 2 Ibid. 3 Ibid. 4 Ibid. 5 Gary Graff, "Driving Hard Down the No-Clean Track", Electronics Manufacture and Test, December 1989. 6 "Intel Completes Elimination of CFCs from its Santa Clara, CA Plant", Business Wire, 25 November 1991. 7 Apple Computer Inc., (U.S.). 8 Ecoclean, Ltd., (U.K.). 9 Rick Wartzman, "GM Unit Discovers Solution for CFCs, and It's a Lemon", Wall Street Journal, 22 January 1992. 10 Business Wire, 1991. 11 Northern Telecom, (U.S.). 12 Japan Industrial Conference for Ozone Layer Protection (JICOP), The 1990 Survey. 13 OECD, June 1991: David O'Connor, "Strategies, Policies and Practices for the Reduction of CFC usage in the Electronics Industries of Developing Asia". 14 Motorola Corporation (U.S.) and U.S. Sandia National Laboratories: joint research project. 15 Digital Equipment Corporation (U.S.). 16 U.S. Environmental Protection Agency (EPA), June 1991: "Eliminating CFC-I 13 and Methyl Chloroform in Precision Cleaning Operations". 17 UNEP, 1991. 18 U.S. EPA, 1991. 19 Ibid. CHAPTER Vl AEROSOLS 6.1 Summary In 1989, the aerosols sector accounted for approximately 20% of total CFC consumption worldwide 1. Major applications include medical, industrial, technical, household and personal care products. Since the late 1970s, CFC use in the aerosols sector has declined dramatically, including a 58% worldwide decline since 1986 2. Nonetheless, CFCs are still used as propellants, despite the wide range of alternatives available. These include, among others: non-spray dispensing methods, mechanical spray dispensers, compressed gas and hydrocarbon propellants and dry powder inhalers and nebulizers for medical inhalent use. The above alternatives cover every major CFC application in the aerosols sectors. The use of CFCs in metered dose inhalers for asthmatic patients is generally recognised as the only "essential use". However, a combination of alternatives (e.g. dry powder inhalers) and CFC recycling should eliminate any need for new CFC production. 6.2 Statement of the problem: current uses of ozone-depleting chemicals in the aerosols sector 6.2.1 General considerations In 1989, worldwide CFC consumption in the aerosols sector was 180,000 tonnes. CFC-11 and CFC-12 are most commonly used for aerosol applications. CFC- 113 and CFC- 114 have been used for specialised purposes 3. CFCs have been used primarily as propellants in aerosol products, although they have also been used as solvents when the product itself requires dissolving. In addition, they are sometimes used as the active ingredient when special functions are required, such as chilling, rapid evaporation and generating noise. The major areas of application are: medical (e.g. metered dose inhalers, antiseptic sprays), industrial and technical (e.g. high quality moulded plastics and elastomers, electronics and electrical cleaners, lubricants and aircraft maintenance products); and household and personal care products (e.g. hairsprays, deodorants and anti-perspirants) 4. During the 1960s and early 1970s, CFCs were widely used in aerosol products. However, since the late 1970s, CFC use as an aerosol propellant has substantially diminished 5. Nonetheless, CFCs are still extensively used as propellants in industrial and technical speciality products and metered dose inhalers (MDIs) for asthmatic patients. These applications are often exempt from existing regulations as substitutes have not been widely recognised. HCFC-22 and blends of HCFC-22 with dimethyl ether and methyl chloroform are being used instead of CFCs for specialty products 6. The most controversial area in terms of alternatives remains the use of CFCs in metered dose inhalers. Metered dose inhalers contain the drug to be delivered, a propellant (usually a mix of three CFCs) and a surfactant. Currently, CFC-12 and CFC-14 are used as propellants, with CFC-11 as a solvent and slurrying agent. In total, some 300 million metered dose inhaler units were sold worldwide in 1990, with an average capacity of 10 to 20g of CFCs per unit 7. It has been estimated that metered dose inhalers use 0.4% to 0.5% of worldwide annual CFC consumption 8, Metered dose inhaler manufacturers are claiming regulatory exemption until 1998-2000 at the earliest, on the grounds that this application is lifesaving and that no satisfactory alternatives currently exist. Today, inhaler applications are the most widespread exemption for CFC use internationally. The amount of CFCs used annually worldwide for inhalant drug products (5,000 to 6,000 tonnes) is expected to increase 9. 6.3 The alternatives 6.3.1 General considerations A broad range of alternatives to CFCs are already in wide use. Alternative application methods such as roll-ons, sticks and other non spray dispensers for a variety of household and personal care products are well established. Also, alternative propellants such as hydrocarbons and compressed gases, as well as mechanical spray dispensers, are being used in a wide range of products such as gels, creams, disinfectants, hairsprays and lubricants. The most common alternative propellants have been the hydrocarbons propane, butane and isobutane. However, their use presents some environmental concerns. 6.3.2 Defining what is 'essential' Many market-driven CFC propellant applications are either frivolous or unnecessary. The only application in which CFCs could still be considered "essential" would be the use of metered dose inhalers. However, even in this area, dry powder inhalers, nebulizers and other inhalant and noninhalant products can be used to replace much of the CFC use. Moreover, CFCs can be recycled to necessary levels of purity for use in inhalers such that no new CFC production is essential. 6.3.3 Safest known alternatives (a) Alternative dispensing methods Products using non-spray dispensing methods are already well established in the market. For example, deodorants, hair products and anti-perspirants are now all available in non-spray forms such as gels and creams from glass bottles, solid sticks and rollon ball dispensers. One variation of the solid stick has recently been developed to package carpet spot removers 10. Other products, such as paint and polishes, can be applied using traditional methods such as brushes and pads. Spray formulations of furniture polish can be completely replaced by paste or liquid formulations. Dusting sprays can be replaced completely by damp cloth application methods. Many other examples exist. (b) Mechanical spray dispensers A U.S. company distributes a mechanical pressure dispenser comprising a two-compartment, self-pressurised, rubber bladder system 11. It uses a bottle which can be recycled and is fitted with a valve, inserted in a rubber sleeve, placed in an outer container and filled. The product is delivered by the contraction of the sleeve. The system can be adapted to most product viscosities. It also has potential for medical products since the internal unit can be sterilised before or after production and the system itself is airtight 12. Companies are currently using this system in household products, personal care products, welding sprays and lubricants. Finger and trigger pumps, consisting of a bottle and an attached pump valve, are also being widely used commercially, mainly for personal care and household products. Demand for them is growing rapidly. Spray pumps deliver active product without the need for additional solvents or propellants, making them particularly suitable for cosmetic applications. These systems are already widely used. To date, finger pump sprays have taken over about 30% of the hairspray market and 80% of the window cleaner market in the U.S. 13. The absence of propellant means that a small container can provide the same volume of product as a larger-sized aerosol can, thus reducing solid waste. Further reduction of solid waste should result from the recent marketing of a refillable trigger spray product using a dual bottle system 14. One limitation to spray pumps in the past has been their inability to produce a fine, dry spray. However, a delivery system is now being used by one of the largest hair product companies that produces a fine, relatively dry spray 15. (c) Compressed gas propellants (carbon dioxide, nitrogen and air) Nonflammable compressed gases such as carbon dioxide (CO2), nitrogen (N2) and air can be used as aerosol propellants where medium to coarse sprays are acceptable. These propellants are currently used in some 7 to 9% of aerosol products worldwide including cleaning and automotive products, disinfectants, brake cleaners and silicon sprays 16. Compressed gases must be used in two compartment 'barrier pack' systems in which a solvent is added to the product itself. These generate more solid waste because they need more head space for the gas to maintain sufficient pressure. Some pressure problems have arisen using compressed gases. However, U.S. and European companies have recently developed a two-part compressed gas propellant system which mitigates spray quality and pressure problems by releasing pressure internally into the can. The design uses a very small volume of propellant 17. Another new compressed air propellant developed by a U.S. company is used with a range of waterbased mould release agents for high quality plastics and elastomer moulding operations. Although it sprays a larger particle size than the same application using CFCs, the developer says this problem is being dealt with by modification of the sprayer design. A fully enclosed system is also being developed by the same company for continuous processes 18. Compressed gases can also be used in some specialised technical applications. For example, carbon dioxide is used extensively as a coolant in pipe frosting applications in Germany 19. Liquid nitrogen is also widely used as an alternative to CFCs for localised refrigeration techniques 20. (d) Dry powder inhalers Dry powder inhalers, which contain the drug to be delivered in powder form with a lactose or glucose carrier, are currently being used by about 10% of patients requiring inhaled medicine worldwide 21. In Sweden and the Netherlands, however, the percentage of asthmatics using this delivery system is 65% and 61%, respectively. In fact, in Sweden, inhalers using CFCs are banned unless special permission is granted by the Medical Inspectorate in consultation with the Swedish EPA. Furthermore, all HCFCs will be subject to the same regulation as of January 1994 22. Dry powder inhalers are produced by all four major manufacturers of metered dose inhalers. They cannot be used effectively by children under 4 years and cost more than metered dose inhalers because of the two-stage process needed to produce correct particle size. However, the tendency to use a single dose with this delivery system, compared to metered dose inhalers, which often are associated with multiple doses, partially offsets the price differential 23. The major disadvantage of dry powder inhalers is that the patient's inspiratory flow has to be above a certain level to ensure adequate drug delivery. However, one specialist has concluded that the vast majority of patients with acute asthma would be able to use dry powder inhalers 24. (e) Nebulizers Nebulizers provide a non-irritating, air-propelled delivery system for inhalant drugs. There are two disadvantages to the system. The delivery time is long: administration of the medication takes about 10 minutes, rather than 20 seconds with metered dose inhalers or dry powder inhalers. They are also more costly than metered dose inhalers and dry powder inhalers as the system requires a compressor which represents an extremely expensive - although one-off - cost for the patient. However, they are widely available for hospital use and transportable, personal-size nebulizers are being developed. (f) Other inhalant and non inhalant medical alternatives Pills, powders, drops and mechanical pump sprays are all widely available and are efficient methods of delivering inhalant drugs. They are not suitable, however, for measured dosage drugs. Other non inhalant uses such as antiseptics, anti-fungal agents and local anaesthetics can all be replaced by mechanical pump sprays or powders. 6.3.4 Other alternatives (a) Hydrocarbon propellants The most commonly used alternative propellants have been the hydrocarbons propane, butane and isobutane. In the U.S., where CFC use in aerosols was banned in 1978, hydrocarbons now account for about 85% of the propellant market 25. They also function as solvents in 40 to 50% of aerosol products in the U.S. 26. Another common propellant is dimethyl ether. This is a medium to high pressure organic liquefied propellant, which accounts for 5% to 10% of the hydrocarbon market worldwide 27. It is used extensively in some European countries. These compounds, however, cannot be regarded as environmentally acceptable in the long term, as they are volatile organic compounds and contribute to tropospheric smog and global warming. Shifts to hydrocarbon propellants have been hampered by government legislation in countries such as the U.S., U.K., Japan and France. 6.4 Conclusion Alternatives exist for every major CFC application in the aerosols sector. The majority of historic CFC use in this sector has already been replaced by alternatives. The only remaining application in which CFCs cannot be completely eliminated on an immediate basis is metered dose inhalers for asthmatic patients. Some MDI use can be replaced by the use of dry powder inhalers, nebulizers, mechanical pump sprays and non-inhalant methods. However, at least in the short term, some recycled CFCs will need to be used for medical inhalers. There should be no insurmountable obstacles to purifying recycled CFCs for this purpose. It should be noted that the 5,000 to 6,000 tonnes of CFCs consumed in 1989 for this purpose represented 0.3% of total worldwide CFC use, and this figure could drop dramatically if dry powder inhalers and other alternatives were more widely used, as in Sweden and the Netherlands. References to Chapter Vl 1 United Nations Environment Programme (UNEP), December 1991: Montreal Protocol 1991 Assessment, Report of the Aerosol Products, Sterilants, Miscellaneous Uses and Carbon Tetrachloride Technical Options Committee. 2 Ibid. 3 Ibid. 4 Ibid. 5 Ibid. 6 Ibid. 7 Ibid 8 S.P. Newman, "Metered Dose Pressurised Aerosols and the Ozone Layer", European Respiratory Journal 3, 1990. 9 UNEP, 1991. 10 Green Market Alert, May 1991: "Environmentally Friendly Aerosol Alternatives Hit Town". 11 Judi Topper, Kurt P. Ross Agency (for Exxel Company - U.S.): personal communication, March 1992. 12 Ibid. 13 Robert Mcmath, "It's all in the Trigger", Adweek's Marketing Week, 6 January 1992. 14 Mcmath, 1992; Elaine Matthews, Proctor and Gamble Co. (U.S.): personal communication, March 1992. 15 Ibid. 16 UNEP, 1991. 17 Charlie Rummel, BOC (U.S): personal communication, February 1992. 18 Ralph Engel, Chemical Specialities Manufacturers Association (CSMA) (U.S.): personal communication, March 1992. 19 G. Pahlike, "Other Uses of CFCs", in Responsibility Means Doing Without (Umweltbundesamt. Berlin: 1989). 20 Ibid. 21 UNEP, 1991. 22 Mats Abrahamsson, Greenpeace Sweden: personal communication, September 1992. 23 Dr. M. Huybrechts, Astra Pharmaceuticals (Belgium): personal communication, February 1992. 24 G.K. Crompton, "Dry Powder Inhalers: Advantages and Limitations", Journal of Aerosol Medicine, Vol. 4, 1991. 25 Ron Davis, CCL Custom Manufacturing (U.S.): personal communication, March 1992. 26 Ibid. 27 UNEP, 1991. CHAPTER VII FOAMS 7.1 Summary In 1990, global CFC consumption in all foam sectors was 168,000 tonnes 1. Many foam product applications still use CFCs, including CFC-11, CFC-12, CFC-113, and CFC-114 2. The long-term acceptability of foam products must be re- assessed. Not only do polyurethanes and polystyrenes present environmental problems in their own right, but isocyanates used for polyurethane foam production are themselves environmentally damaging, being made from chlorinated intermediates and phosgen. The foams are also nonbiodegradable which exacerbates environmental disposal problems. Furthermore, some of the uses to which these products are put are unnecessary (e.g. packaging, cushions, steering wheels, and headrests in automobiles). There are many traditional alternatives to polyurethane and polystyrene foams, such as fibreglass and fibreboard as insulating materials, paper and cardboard as packaging materials, and products made of rubber and leather. Each of these are widely available. Although traditional insulation materials have higher thermal conductivities, use of thicker sections will compensate. Alternative foam-blowing agents, including carbon dioxide, carbon monoxide, water and pentane are being used increasingly in foam production. Design techniques such as using panel cover layers can greatly improve insulation properties of foams blown with these alternative agents. Other technologies such as vacuum and silicon aerogel insulation panels, will become commercially available in the near-term. 7.2 Statement of the problem: current uses of ozone-depleting chemicals in the foams sector 7.2.1 General considerations Foam plastics are manufactured by introducing a gas or a volatile liquid into a liquid plastic. In some foams the gas creates a closed-cell structure that contains the blowing agent and in others the gas escapes and open-cells are produced. The rigid, closed-cell plastic foam insulations have the highest thermal resistance per unit thickness of all commercially available insulations. CFCs-11, -12, -113 and -114 are still used widely in foam product manufacture. A breakdown shows that in 1990, 141,000 tonnes (84%) were used to produce polyurethane foam; 12,350 tonnes (7%) for polyolefin foam production; and 12,000 tonnes (7%) and 2,700 tonnes respectively for extruded polystyrene and phenolic foams. These products were used primarily for building and appliance insulation applications (140,000 tonnes or 83% of the total) as well as cushioning, packaging, flotation and microcellular foams (28,000 tonnes). About 75% of the rigid polyurethane foam was used worldwide in refrigerators and freezers 3. 7.2.2 Types of foams (a) Polyurethane foams Polyurethane foams are made by blowing CFCs into a polymerising mixture of isocyanates and polyols, thus forming gas bubbles. They can form (i) rigid foams, which have closed-cell structures; (ii) flexible foams, with open-cell structures; or (iii) integral skin foams (both rigid and semi-rigid) which are low density, open-cell flexible foams with high density skins. (i) Rigid foams A rigid polyurethane foam has a closed-cell structure that contains the blowing agent and usually has a low thermal conductivity. Consequently, these products are used as insulating materials in industrial and building applications as rigid bunstock or laminated boardstock, poured-in-place foams and spray-applied foams. About 75% of the rigid polyurethane foam used in home appliances is for refrigerators and freezers; the remaining use is for display cabinets, water heaters, portable coolers, commercial appliances and vending machines 4. Sprayed foam is prepared at the application site using a hand- held spray gun that mixes and dispenses plastics under pressure. The foam is applied in layers to insulate roofs, walls, containers, transport vessels and refrigeration chambers. The sprayed foam process facilitates coverage of large and complex structures. (ii) Flexible foams Flexible and moulded polyurethane foam has been used as cushioning material for furniture, upholstering, mattresses, car seats, back cushions and head rests, and packaging for over 40 years. Raw materials are mixed at room temperature and react to yield a polymer product that is expanded with a self-generated carbon dioxide blowing agent. The raw material mixture includes water as a chemical blowing agent since it reacts with the isocyanate to produce carbon dioxide. The CO2 has been traditionally supplemented with up to 15% by weight of CFC-11 to produce foams for use as packaging materials. These "water- blown" foams compose about 40% of the total slabstock foam that is produced. CFCs are used to reduce the density, and prevent the formation of urea during water-blowing 5. (iii) Integral skin foams Rigid integral skin polyurethane foams are used for computer cabinets, skis and tennis rackets. Semirigid integral skin polyurethane foams are used for steering wheels, headrests, armrests and shoe soles. In production, the formation of a massive outer skin is caused by the use of CFCs which are retained in the closed cell. Steering wheels prior to 1990 contained about 10% (by weight) of CFC-11 whereas, worldwide, 7% of all shoe soles (40% of sport shoes) are produced from polyurethane foam using CFC-11. (b) Polystyrene foams Rigid extruded polystyrene foam is produced by high pressure extrusion of molten polystyrene containing CFC-12. Globally, about 90% is used as rigid foam boards for thermal insulation purposes. The remainder is used as foam sheet for disposable packaging. 7.3 The alternatives 7.3.1 General considerations There are many traditional alternatives to polyurethane and polystyrene foams. Traditional insulation materials such as fibreglass and perlite (volcanic rock), and insulation materials produced with alternative blowing agents, generally have a higher thermal conductivity than CFC-blown foams. However, compensation for this is possible, as outlined below. The global foam plastics industry has been evaluating a variety of alternative blowing agents such as carbon dioxide, water and pentane. The alternatives are coming into much wider use as technological advances improve insulation capabilities and other properties. Obstacles to wider replacement of CFC-blown foams with more traditional materials are related more to market forces and consumption patterns than to technical problems. 7.3.2 Defining what is 'essential' There are no 'essential uses' of CFC-blown foams. Furthermore, thought must be given to the very acceptability of producing foams in the long-term. Not only are polyurethanes and polystyrenes produced using environmentally-damaging production processes, but they are also non-biodegradable, exacerbating environmental disposal problems. Therefore, the first priority in considering alternatives is whether foams should be produced at all. 7.3.3 Safest known alternatives (a) Alternative materials There are many traditional materials which can be used as alternatives to polyurethane and polystyrene foams: (i) Insulating materials Fibreglass Rock wool Cellulose Perlite (volcanic rock) Vermiculite Fibreboard Cellular glass Insulating concrete Gypsum Plywood Insulating brick Cork (ii) Packaging materials Paper Cardboard (iii) Other applications Leather Rubber The alternatives listed above are widely available and cost- competitive with CFC-blown foams. Although the insulation materials have higher thermal conductivities, use of thicker sections will compensate. Thicker insulation using traditional materials is common in home and building construction. In the U.K. construction industry, 80% of insulation materials are made from non-CFC mineral fibres 6. One British company has sold over 750 million cubic metres of perlite roof insulation board over the past 20 years 7. Since 1986, when over 80% of the CFCs used for polystyrene was for foam sheet packaging, many companies such as fast food chains have switched to more traditional materials such as paper and cardboard. (b) Modified foam blowing processes (i) Carbon monoxide In order to cut down on CFC use in polyurethane production, process modifications have been introduced. One alternative foam blowing process involves adding formic acid salt to the raw material mixture to yield carbon monoxide as an additional blowing agent 8. (ii) Water A large producer of upholstering in Europe has switched to CFC- free polyurethane foam production with the help of a special type of system using higher molecular weight polyols. In this technology, water only is used as the blowing agent for the foam process. The physical properties of the foam are equivalent to the material formerly produced with CFCs 9. Similar systems involving polyol, isocyanate and water are envisaged for moulded foam production. The industry is trying to move away from the use of CFC-11 as a blowing agent and very few problems have been caused by this change since the desired foam has a relatively high density. However, industry claims that switching to CFC-free solvents as separating agents for the moulds is difficult. Nonetheless, the problems are only that water-based release agents have longer evaporation times and are more expensive 10. A 'foam-in-cover' method which places the flexible foam on the cover fabric is now being used to avoid the need for CFC separating agents. Only the metal mould lid needs to be treated with separating agents. In 1988, a large U.S. company introduced 'foam-in-cover' seats. European companies have also used this technique ll. Four German companies now use a water-based separating agent which has reduced the use of CFC-11 by 307 tonnes annually. Many recent studies have shown that CFC-11 may be replaced by 'water blowing' to produce integral skin polyurethane foams. (iii) Carbon dioxide (CO2) Carbon dioxide has been used to replace CFCs in rigid polyurethane foam production. In this process, the CO2 blowing agent is generated from water/isocyanate reactions. However, CO2 is a relatively small molecule and passes through the foam cell walls quickly. Therefore, the insulating capacity is reduced more quickly. To compensate for this, industrial construction applications often use so-called 'sandwich panels,' which have metal covers on both sides to reduce oxygen and nitrogen intrusion, and escape of the blowing agent. These cover layers can improve mechanical properties and the long-term insulating capacity of CO2-blown products. By increasing the water content of some foam formulations, complete CO2-blowing can be accomplished, which totally eliminates the use of CFC-11. For some time, a German company has been offering completely CFC-free, water-blown insulating panels with flexible cover layers that allow diffusion 12, These are useful for a variety of different insulating purposes. These processes, although somewhat more expensive, are technically proven and CO2/water-blown foam is being used increasingly. Complete substitution of CO2 for CFC-11 in foam production is already being done for water heaters where the foam thickness can be increased to compensate for the decreased insulating capacity of a totally CO2-blown foam. The foam used in refrigerators strengthens the walls and serves as insulation. Selection of CO2-blown foams will require increased foam thickness to avoid higher energy consumption. Although this will mean that either the external dimensions of the refrigerator will be greater or the internal dimensions smaller, both choices are preferable to the use of CFCs. Research is attempting to overcome this problem by producing smaller cells in the polyisocyanurate foam, thus reducing CO2 diffusion. Sprayed foam can also be blown using CO2. In Europe, several companies market sprayed foams that contain no CFCs and that can be processed using conventional foam machinery. Although the initial and aged thermal conductivity is as much as 25% higher than that for sprayed foam produced using CFC-11, thicker insulation is possible in most building applications 13. In 1991, a leaking plant roof in Germany, with an area of 1,500 m2, was covered by a layer of foam 4.5 cm thick. This was the largest area in Germany ever spray-foamed without using CFCs. Previously, about 1,000 kg of CFC-11 would have been required for this 70 m3 installation 14. A new process has also been developed that allows CO2 alone to be used to produce polystyrene foam sheet. (c) Other insulation techniques Vacuum insulation is also being developed to replace CFC-blown foam insulation in refrigerators. Composites of either vacuum panels or gas-filled panels encased within a lower thermal resistance foam can achieve higher thermal resistance than CFC-11 and CO2/water-blown foams. Lower energy consumption of refrigerators using vacuum insulation panels would reduce impacts on global warming. Several vacuum panel technologies are being examined. For example, an evacuated panel, with diatomaceous earth as the filler in a cylindrical metal barrier to insulate steam lines, has been developed by a German company 15. A large U.S. company is also developing evacuated panels containing precipitated silica 16.17. Lawrence Berkeley National Laboratories (U.S.) and a private U.S. company are in the process of commercialising a silica aerogel insulation panel that has a thermal resistance three times lower than that of a CFC-11-blown foam 18. Vacuum panels consisting of glass and metal enclosed compacts of precipitated silica and flat panels filled with a low thermal conductivity gas such as argon or krypton are also being developed 19. It should be noted that some of the components being considered in vacuum insulation systems (e.g. HFCs, plastics, and flyash) are environmentally unacceptable. 7.3.4 Other alternatives Manufacturers are also intensifying their search for new blowing agents and turning to chlorinated hydrocarbons and hydrocarbons such as N-pentane, butane, isopentane and isobutane 20, 21. However, in general, these cannot be considered acceptable long- term substitutes because of their persistence, bioaccumulation in food chains and toxicity properties, among others. (a) Pentane Pentane is being employed increasingly as a foamblowing agent. For example, it is being used to make CFC-free steering wheels by some German producers. A U.S. manufacturer is also using pentane to blow integral foam for automobile armrests 22. A new method is also being developed that uses pentane to produce thermal insulation panels and laminated boards. The use of pentane on a broad scale is being extensively investigated by industry, particularly in Europe, since pentane is relatively inexpensive and widely available. However, pentane is a volatile organic compound and emissions from such compounds, which contribute significantly to smog formation, are already regulated by some countries. It cannot be considered an environmentally acceptable alternative in the long-term. (b) Other hydrocarbons A foam-blowing system has been developed in Germany for use in shoe soles which uses iso-paraffins (de-aromatised hydrocarbons of a higher boiling point) 23. 7.4 Conclusion Alternatives to CFCs exist today for all major applications in the foams sector. Alternatives include traditional insulation and packaging materials, alternative materials such as leather and rubber, alternative foam-blowing agents such as CO2 and alternative insulation technologies such as vacuum panels. There can be no justification for any further use of CFCs in foam production. Some of the main arguments in support of further CFC use involve superior insulation properties of CFC-blown foams. However, thicker insulation using traditional materials, technologies such as insulation panel cover layers for foam blown with CO2 and other agents, and new technologies such as vacuum panels, can adequately compensate. References to Chapter VII 1 United Nations Environment Programme (UNEP), December 1991: 2 Ibid. 3 Ibid. 4 Ibid. 5 Ibid. 6 Friends of the Earth, 1989, "Safe as Houses? CFCs in Buildings: Insulating Foams and Air Conditioning". 7 Euroroof, Ltd. (U.K.): personal communication, May 1991. 8 H. Creyf, "Alternatives to Fully Halogenated CFCs in the Production of Polyurethane Foams", International Conference on Alternatives to CFCs and Halons, Berlin, February 1992. 9 Ibid. 10 Ibid. 11 K-Plastik & Kautschuk Zeitung (Germany). 12 Paul Bauder Company (Germany). 13 Bayer AG and Rhein Chemie Reinnau Gmbh, Baymer DS-2 Dachspritzschaum (Germany). 14 Mr Reiser, Elastogran Polyurethane GmbH (Germany): personal communication, March 1992. 15 L. Schilf, "Experience from Development and Five Years Application of a New German Vacuum Insulation", 1990 ASHRAE Annual Meeting, St Louis, June 9-13. 16 R.W Barito and K.L. Downs, "Precipitated Silica Insulation", Assignee: GE Company, U.S. Patent 4,636,415, 13 January, 1987. 17 R.W. Barito & K L Downs, "Insulation Formed of Precipitated Silica and Fly Ash", Assignee: GE Company, U.S Patent 4.681,788, 21 July 1991. 18 A.J. Hunt and C.A. Jantzen, "Aerogel, a High Performance Insulating Material", p. 455-463, in ASTM STP 1115, Philadelphia, 1991. 19 L.R. Glicksman and M.S Burke, "Thermal Insulations Using Vacuum Panels", Assignee: Massachussets Institute of Technology, U.S. Patent 5,032,439, 16 July 1991. 20 Industrieverband Polyurethan- Hanschaum e.V. (IVPU), Stuttgart, 24 February, 1992, CO2/Pentangetriebene PUR- Schaeume. 21 G. Heilig, Pentan - eine FCKW-Alternative fuer Polyurethane Hanschaumestoffe, in: Kunstoffe 81 (1991) 7, S. 622 ff; G. Heilig, u.a. Brandverhalten, Pentan-getriebener Polyurethan- Urethanes Technology 8 (1991), June/July. 22 J.H. Schult, "PUR Integral Foam without CFCs," proceedings from Montreal Protocol 1991 Assessment, Report of the Flexible and International Conference on Alternatives to CFCs and Halons, Rigid Foams Technical Options Committee. Berlin, February 1992. 23 J. Hinrichs, Air Products and Chemicals, PURA Cmbh & Co.: personal communication, March 1992. CHAPTER VIII FIREFIGHTING 8.1 Summary Halons are among the most commonly used fire extinguishing agents and have a considerable overall impact on ozone depletion. The three compounds most widely used today are Halons 1211, 2402 and 1301. The functions which halons serve in many fire and explosion protection applications can be satisfied by a wide range of alternatives. For example fire prevention and loss reduction practices, such as employing fire-resistant materials and early detection surveillance systems can be employed. Alternative extinguishing agents which are already in wide use include carbon dioxide, water, foam and powder. The new carbon dioxide/nitrogen/argon mixture could be a major breakthrough in replacing Halon 1301 fixed systems. This could mean that in the very near future there would be no generally recognised 'essential uses' of halons. At present, some applications such as protection of aircraft cabins are still considered as 'essential uses.' Any uses deemed essential can certainly be met by the existing halon bank. There can be no justification for continued halon production. 8.2 Statement of the problem: current uses of halons in the firefighting sector Halons are a family of halogenated hydrocarbons which are among the most commonly used fire extinguishing agents. The three compounds in common use today, Halons 1211, 2402 and 1301, have been used as fire extinguishants since the early 1970s. Although halon consumption is less than 3% by volume of total ozone depleting chemicals (ODCs) consumption, they are the most potent ozone depleters 1. For example, Halon 1301 is roughly ten times as potent an ozone destroyer as the baseline chemical CFC-11. Halons cause significant environmental damage at the Earth's surface, as well as in the stratosphere. Halogonated hydrocarbons in general have been recognised for over 20 years as a priority source of industrial pollution warranting urgent action to protect marine ecosystems. In 1990, the estimated 'CFC equivalent' (i.e. weighted comparison to the baseline chemical CFC-11) of worldwide halons production was over 130,000 tonnes 2. Halons are used for a wide variety of applications in both portable and fixed systems, with their primary use in fixed systems. The two types of fixed systems in which halons are used are 'total flood' (where a uniform concentration of extinguishing agent is built up within the protected space) and localised (where the agent is discharged directly onto the flammable materials). Halons are used to combat specialised fire and explosion situations, including computer and electronic equipment facilities, museums, engine spaces on ships and aircraft, ground protection of aircraft and facilities for processing and pumping flammable liquids. They are also used for general office and industrial fire protection applications, as well as residential use. Halon 1301 is used primarily in fixed flooding systems, although there is a considerable number of portable Halon 1301 extinguishers. Halon 1211 and 2402 are generally used as streaming agent extinguishants, primarily in portable fire extinguishers. 8.3 The alternatives 8.3.1 General considerations A number of alternative extinguishing agents are available. All of these are considered 'not-in-kind' replacements, requiring some modification of existing systems and equipment or new construction. The class of fire for which protection is being provided (e.g. electrical, solids, flammable liquids) influences the choice of extinguishing agent. The substitution of halons in fixed systems is considered to be more difficult than in portable extinguishers. Replacement with an alternative extinguishing agent is the main route for the ultimate elimination of halons in portable extinguishers and already alternative agents are widely used 3. Aircraft cabins are one of the very few applications where these agents may be inappropriate. For the vast majority of cases there is no need to use portable halon extinguishers. In the case of halon use in fixed systems, the first step toward reduction and elimination must be to reduce risk through fire prevention measures and ensure staff are adequately trained. Secondly, fire damage needs to be limited by a number of measures as described below. Finally, fixed halon systems must be replaced with systems using the alternative agents described below or possibly new agents developed in the future. 8.3.2 Defining what is 'essential' The environmental consequences of ozone loss must be carefully weighed against any further use of halons - even uses that are today widely regarded as essential. The debate around 'essential uses' of halons has drawn considerable attention. However, the vast majority of halon use cannot be considered essential. One ongoing practice which must be immediately recognised as not being essential is the release of halons during testing and training exercises. Alternative test chemicals and/or testing procedures are now available and must be made mandatory. 8.3.3 Safest known alternatives (a) Alternative approaches to fire protection A detection and suppression scheme is only one part of an adequate fire protection system. Fire protection is not simply the provision of portable extinguishers or fixed extinguishing systems. In assessing the potential for reducing and eliminating halon use, it is necessary to consider not only direct extinguishing agent alternatives but also other approaches to achieving a suitable level of protection. This involves a combination of measures to mitigate fire and loss potential. Precautionary measures include reducing and eliminating the potential for ignition and ignition sources by improved design of buildings and interiors; using materials that prevent fire spread and damage (e.g. installation of less flammable cables and cables that produce less smoke and toxic gases); protecting individual electronic equipment cabinets rather than the entire volume of the room in which they are housed; isolating the equipment at risk in a smaller area separated by fire-resistant construction; early warning and detection through increased surveillance of key installations; and contingency planning (e.g. duplicating records) 4. These measures alone afford significant potential for reduction in the use of fixed halon extinguishing installations. Another option is to eliminate halon-based fire protection equipment without replacement by an alternative method of fire extinguishing. Known as the 'zero protection option,' it can be considered appropriate in situations where the fire hazard to common electrical appliances such as electronic typewriters and personal computers has been overemphasised 5. The zero protection option has limited application. (b) Carbon dioxide (CO2) In terms of technical performance, the alternative agent which most closely emulates halons is carbon dioxide. Like halons, it is a gas at ambient temperature and pressure. It shares many of the advantages of halons: it is non-conducting and exhibits good penetrating capability. Before the current popularity of halons, carbon dioxide systems were used for many of the applications for which halon systems are now installed (e.g. the protection of computer installations) 6. Fixed carbon dioxide systems remain in wide use for a number of applications, particularly unoccupied spaces. Carbon dioxide is, however, less efficient than halons, therefore the size and weight of the storage requirements are greater. In the case of a space that is continuously occupied or frequently visited, a carbon dioxide system would need to be manually discharged. This system can also be used for in-cabinet protection where the agent is discharged directly into the electronics cabinet. Carbon dioxide portable extinguishers have also been available for many years and are in wide use. Compared with Halon 1211, CO2 portable extinguishers are larger, heavier and have shorter agent throw. Since replacing halon with carbon dioxide extinguishers may leave a building without sufficient extinguishing capabilities for some fires, a combination of carbon dioxide, water and/or foam may be required as the most suitable alternative to halon use in portable extinguishers. (c) Carbon dioxide, nitrogen and argon mixture A newly developed gas mixture, composed of the common atmospheric gases carbon dioxide, nitrogen and argon, is being marketed by a U.K. company 7. The presence of the carbon dioxide stimulates the respiration of anyone trapped in the area where the gas is released. The new mixture could be an important breakthrough and an effective alternative to Halon 1301 in fixed, full-flooding systems for computer suites, engine rooms, and other applications. Converting an existing halon system to this gas system requires a change in release nozzles and storage tanks; the existing halon pipework can be used 8. The mixture has already been officially approved for use in the Netherlands and Denmark and is now being tested in Germany. The U.K. will soon begin tests as well 9. (d) Water Another alternative for some halon applications is water. Automatic sprinkler systems were first developed in the last century and are a well-proven, highly reliable form of fire protection, particularly in general industrial and commercial premises. Water is a very effective extinguishing agent because of its unusually high specific heat and heat of vapourisation. It extinguishes fires involving burning solids primarily by cooling the fuel to a temperature below the fire point. Testing has shown that fine water sprays can be very effective fire extinguishants and have the additional benefit of cooling to prevent reignition. The quantity of water required is, in some installations, less than the equivalent amount of halon needed for the same fire scenario. Automatic sprinklers may be used for protection against many of the hazards for which halons are traditionally used, such as protection of electrical equipment. To avoid damage to the equipment, however, it is necessary to de-activate the power supplies before water is discharged. Water extinguishing applications include flammable liquid fires, suppression of explosions, protection of enclosed electronic equipment and possibly protection against fires in aircraft cabins. 8.3.4 Other alternatives (a) Foam Foams are a suitable alternative to halons for certain flammable liquid hazards. Low- and medium expansion foam systems are generally used to extinguish fires by establishing a barrier between the fuel and air. Drainage of water from the foam also provides a cooling effect which is particularly important for flammable liquids with relatively high flash points. Aqueous Film Forming Foam (AFFF) may be used for protection against certain hazards such as engine fires. High-expansion foam systems are uncommon but can be used for total flooding 10. Disadvantages of such systems include greater weight and space requirements, the need for a suitable water supply and possible clean-up problems. These foams also have potential for secondary damage. They cannot be used on fires involving electrical equipment without careful design considerations. Portable foam extinguishers are generally intended for use on flammable liquids, although AFFF extinguishers may also be used for general protection against fires involving solid materials in the same manner as water extinguishers. (b) Powders Certain finely ground powders can be used as extinguishing agents. The mechanism depends mainly on the presentation of a chemically active surface within the reaction zone of the flame. Powders generally provide very rapid knockdown of flames and are considered to be more effective than halons in this regard. Some disadvantages of powder include poor penetration behind obstacles and possible secondary damage to equipment. Fixed powder systems are very uncommon and uses are normally limited to special localised applications such as textile machines or deep fat fryers for which halons would not normally be used. These systems should also be considered for engine space protection. Powder extinguishers are suitable for fires involving solid materials and are often suitable substitutes for flammable liquid fires. They are also suitable for situations where a range of different fires can be experienced, including electrical fires. 8.4 Conclusion Alternatives exist for virtually every major halon firefighting application. The recently developed mixture of carbon dioxide, nitrogen and argon could, according to recent test results, replace Halon 1301, the compound used in fixed extinguishing systems for so called 'essential uses.' Eventually, the environmental consequences of ozone loss must be carefully weighed against any further use of halons. Even if the notion that there are some 'essential uses' of halons is accepted, the supply could be made available from the existing "bank." There can be no justification for new halon production. It is significant to note that several countries have unilaterally taken aggressive action to ban halons. Sweden, Norway, Denmark, Switzerland and Germany have taken the most aggressive action with production phase-out dates as early as 1992. Of course, these decisions must be backed up by tough enforcement measures. References to Chapter VIII 1 United Nations Environment Programme (UNEP), Montreal Protocol 1991 Assessment, December 1991: Report of the Halons Technical Options Committee. 2 Ibid. 3 U.K. Department of the Environment (DOE), London, 1991: "The Use of Halons in the United Kingdom and the Scope for Substitution". 4 Ibid. 5 Ibid. 6 Ibid. 7 Oliver Tickell, "Firefighters Find Gas That's Easy on Ozone", Science, 25 April 1992. 8 Ibid. 9 Ibid. 10 UK DOE, 1991. ABOUT THE WRITERS, EDITORS AND REVIEWERS Bill Brox is a senior researcher with the Swedish Institute of Production Engineering Research (IVF). IVF is the research arm of the Swedish Mechanical and Electrical Engineering Industry. Dr. Brox has worked for a number of years analysing substitutes for CFCs in the solvents sector, and was an expert advisor to the United Nations Environment Programme Solvents Committee. Dr. Brox holds a PhD in Materials Science and Surface Analysis. Sheldon Cohen was the international coordinator for Greenpeace's ozone campaign. He has also worked over the past decade on a number of other environmental issues, including energy and global warming. He holds a Masters Degree in Environmental Science from the University of Wisconsin (U.S). Lee Hatcher is a mechanical engineer for the environmental consulting firm Dames and Moore in the U.S. During fifteen years as an engineering consultant he has worked on design of mechanical refrigeration applied to building air conditioning, as well as halon firefighting systems. Mr. Hatcher wrote his Masters thesis on alternatives to CFCs. Abyd Karmali is an associate with an international consulting firm in Washington, D.C., with several years experience researching alternatives to ozone depleting chemicals. Mr. Karmali has expertise in the technical feasibility and cost assessments of alternatives. He is a chemical engineer, and holds a Masters Degree in Technology Policy from the Massachusetts Institute of Technology (U.S). Thomas Kuehn is a Professor of Mechanical Engineering at the University of Minnesota in the U.S. He has taught courses in refrigeration and air conditioning systems, heating and cooling loads in buildings, and thermal environmental engineering. Andre Leisewitz is Research Director at the Environmental Research Institute Oekologische Briefe in Germany. He has conducted extensive research on alternatives to ozone-destroying chemicals in Germany. David McElroy conducted research in the foams sector for Oak Ridge National Laboratories in the U.S. for many years and served on the UN Environment Program's Flexible and Rigid Foams Alan Miller is Executive Director of the Center for Global Change, an international research and policy organisation working on such issues as ozone depletion, energy policy and global warming. Curtis Moore is an environmental analyst and consultant based in Washington, D.C. Mr. Moore served for eleven years as counsel to the U.S. Senate Committee on Environment and Public Works. He has been involved in the ozone depletion issue for many years. Ted Moore is an environmental research engineer at the Center for Global Environmental Engineering Technologies, at the University of New Mexico in the U.S. He has conducted extensive research on halon alternatives for over a decade and has published widely on the subject. Dara O'Rourke is on the staff of the Pollution Prevention Research Center in the U.S. He has worked for the United Nations Environment Programme on ozone depletion issues in Southeast Asia, and as a consultant to the U.S. Environmental Protection Agency (EPA) on technical and policy issues related to ozone depletion and global climate change. He holds a degree in Mechanical Engineering from the Massachusetts Institute of Technology in the U.S. Alan Pickaver is the international coordinator of the Greenpeace Science Unit. Dr. Pickaver has, in the past, coordinated Greenpeace's international campaigns on toxics and ocean ecology. He holds a PhD in Microbiology. Winfried Schwarz is a researcher at the Environmental Research Institute Oekologische Briefe in Germany. He has conducted extensive research on alternatives to ozone-destroying chemicals in Germany. Jan Sinclair is the international coordinator for Greenpeace's greenhouse effect campaign. She has worked for many years as a journalist covering environmental issues, particularly ozone depletion and global warming. She has also worked as a speechwriter to Mostafa Tolba, Executive Director of the UN Environment Programme.