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| Faq |
About defining danger, risk and safety
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What is the difference between a danger and a risk ? |
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A intrinstic property is a potential danger if this property can produce undesirable effects, for example to the health or the environment. But it becomes a real or significant risk for the safety of health or of the environment only if the target of this danger is significantly exposed to the effects of this property. The level of risk related to the intrinsic property of a chemical depends thus directly on the quantity to which its target is exposed to : if the chemical is not present in significant amounts, there is no risk, whatever the intrinsic danger involved. To take a very simple example, the acid produced by our stomach, has intrinsically a dangerous corrosive property but the quantities released in normal physiologic conditions do not represent a risk and, on the contrary contribute positively to the digestion process. Only excessive amounts produced in some pathologic conditions will generate gastric lesions. |
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How can we manage safety versus dangers and risks ? |
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Since a danger is related to the intrinsic properties of an agent like a chemical substance, it is usually not possible to act on the danger without changing the substance. In many cases however this "dangerous" property contributes to its reactivity and thus to what makes it interesting. On the other hand, it is most often possible to act on a risk since the risk is related to the level of exposure which can be managed by reducing the probability of such exposure. This can be achieved by reducing the level or the frequency of common or accidental emissions or, in some circumstances, by using protecting means as for example in various occupational settings.
Managing the health and/or the environmental safety is thus more a matter of managing quantitatively and globally a risk rather than focusing on the intrinsic properties of chemicals. It is not always easy for scientists from regulating bodies or industry to convince about this because often the public perception or understanding of a dangerous property is often simpler and greater than that the perception of a real level of risk.
For example, in case of an accident or technical incident, it is more "dangerous" to be in an airplane high in the sky rather than sitting in car but, although everybody knows that quantitatively the probability or the risk of car accidents is much higher, most people remains more impressed by the danger that represent airplane accidents.
A chemical with a very dangerous intrinsic property may also contribute negligibly to a risk when its contribution is compared to the global risk of this kind produced by other sources. For example, the contribution of atmospheric emissions of HF, a very "strong" acid to acid rain is relatively negligible when compared with the contributions of other and less strong acids like nitric and sulphuric acids.
In some circumstances, it may even happen that the use of a chemical with a more dangerous property can even decrease a health or environmental risk if its use contribute to quantitatively reduce significantly the global sources of the same risk.
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About global warming and climate change
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What is the "greenhouse effect" ? |
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The earth is surrounded by its gas atmosphere mainly composed of oxygen and nitrogen but also of other gases including carbon dioxide, (C02) methane (NH4), nitrous oxides, water vapour and other gases of industrial origin. An intrinsic property of these other gases is to absorb the energy of the sun radiations captured by the earth and reemitted in the atmosphere, mainly during the night. In absence of this "greenhouse effect", the mean temperature on the earth surface would be about -18 °C instead of around +15°C and this process to "trap" the solar heat contributed to make life on earth possible. |
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What is "global warming" ? |
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The greenhouse effect is not constant and huge variations were observed during the history of the planet. The greenhouse effect becomes an issue when an "overload" of the atmosphere with these greenhouse gases lead to a progressive increase of the mean temperature observed at the earth surface with subsequent potential and dramatical consequences such as climate and sea levels changes. Other chemicals of industrial origin and common use, among which the fluorocarbons, have an intrinsic "greenhouse potential"and could thus potentially contribute to affect the greenhouse equilibrium. |
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About the ozone layer
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About HFCs
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What are the CFCs ? |
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CFCs (chlorofluorocarbons) had widespread uses in many applications, including refrigeration and air conditioning, or the blowing of insulation foams, because their exceptional qualities : for example, their chemical stability make them particulary unreactive and safe. But the side effect of this chemical stability is to allow them, when released, to eventually reach the stratosphere and to be degraded there by strong UV radiation and give rise to ozone-depleting by-products. |
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Why such a debate on HFCs ? |
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For some of the reasons explained relative to risk management and perception, there is sometimes some confusion in the debate over global warming and the use of HFCs as substitutes of CFCs and H-CFCs. Misinformation in this area has forced to argue over the relative merits or pitfalls of particular aspects or intrinsic properties of each refrigerant rather than looking at its performance as a whole.
This does not help to accelerate the process of CFC phase-out and there is still a high level of CFC use in Europe. It is vital that the facts are objectively and responsibly communicated to ensure that informed decisions are made, allowing to maximise safety, health and environmental performance whilst meeting some essential society's needs such as the cold chain involved in food preservation and the eco-efficient insulation of buildings.
HFCs have been demonstrated to offer a broad range of combined benefits, probably more than any other alternative : HFCs are non-flammable, of very low toxicity, do not contribute to photochemical smog and are highly energy efficient thus minimising the greenhouse emissions due to the energy consumption during the life time of the appliance.
HFCs will contribute no more than 1-2% to manmade global warming by the middle of the next century, and that is if we assume a worst case in which not only that industry stands still and uses the same refrigerants for the next 60 years, but also that emissions remain at their historically high levels.
The fact is that, as HCFCs where in a transitional phase, HFCs are now a vital and safe solution to the challenging environmental issue that ever hit mankind : the ozone layer preservation and its recovery. without HFCs, we would not be able to phase out CFCs as quickly while maintaining the vital role refrigeration and air conditioning play in our society. .
All these facts on HFCs show that they are part of the solution, not of the problem.
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What are the economical and technical advantages of HFCs for society ? |
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Because HFCs offer similar technical and beneficial characteristics, particularly a low level of chemical reactivity they can usually replace CFCs in existing equipment, with only minimal modifications. Users of hydrocarbons and ammonia, on the other hand, have to take into account flammability and toxicity . Major modifications or even relocation, involving significant capital expenditure and appropriate training of reliable staff, may therefore be required before existing equipment can be used safely.
International Governmental Conferences and Meetings around the world have acknowledged the products of the HFCs family as important replacements for CFCs and the HCFCs in their most important applications including refrigeration, air conditioning and insulation foam blowing agents. Even if some countries expressed their intention to phase them out on the sole basis of their intrinsic global warming potential, there is no national or international regulation in place yet.
In brief, when evaluated on the appropriate criteria, the HFCs show a clean bill of health from Cradle to grave.
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About HFCs and refrigeration
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How a refrigeration system contributes to co2 emissions ? |
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Carbon dioxide, released during electricity generation or when fossil fuels such as gas, oil and coal are burned to create energy, contributes over 80% to man-made global warming. Other important greenhouse gases like methane and nitrous oxide contribute to another 15% of total man-made global warming. Even in the worst case (complete emissions) HFCs would contribute only by 2 % of the total. |
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How is the market of HFCs ? |
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The HFC Market is growing steadily. In many applications, HFCs offer the optimum solution, combining safety in usewith excellent technical performance. In systems /designed for low leakage rates and high energy efficiency they are often also the most environmentally acceptable solution. As a result, they are now the refrigerant of choice for many in the refrigeration and air conditioning industry. Furthermore, because of their inherent safety characteristics, they are also being used by the pharmaceutical industry as propellants in medical aerosols such as asthma inhalers.
It was always known there would be no technical panacea for the CFC substitution that a number of different solutions would be required and the market would therefore fragment. This has happened in Europe in the domestic refrigeration market, for example, where hydrocarbons are being used as well as, or in place of, HFCs. The reverse is true in the USA where hydrocarbons are not used in domestic systems because of flammability concerns.
For every application, it is important that the user makes an accurate and global assessment of the safety, health and environmental requirements and balances these against cost and technical performance, using this equation to assess all of the options. It is only in this way that an informed decision can be made about the most appropriate system to use.
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In a sustainable development perspective, how the HFCs are a way forward ? |
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The way forward is "Responsible Refrigeration". The perfect zero impact refrigerant has not yet been developed and, since everything man does - including breathing - has an impact on the environment, it is unlikely it ever will.
Responsible Refrigeration - improving safety and health, and minimising the environmental impact of a refrigeration system through good system /design, through maintenance and service of equipment, through training of /designers and engineers and through recovery and recycling - is now industry's focus.
So propane is only explosive if it is emitted, ammonia is only toxic if it is emitted and HFCs are only greenhouse gases if they are released into the atmosphere.
Provided people are given facts rather than emotion, they can make informed, responsible decisions about future safety, health and environmental impact. As governments around the world acknowledge, facts demonstrate that HFCs and the many associated industrial sectors have a vital role to play in this future particularly for such essential aspects as food preservation and air conditioning in the many places where extreme climate conditions make normal life and feeding very difficult.
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