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Chlorofluorocarbons refrigerant pollutant

For example, Brennan (1993) argues that the answer to chlorofluorocarbon (CFC) pollution is not a suit against all the users of spray cans and refrigerators. [Pg.83]

It is the use of LIDAR devices as tools for spectroscopic measurements on the various gases present in the atmosphere which concerns us here. These include ozone, carbon dioxide, the CFCs (chlorofluorocarbons, such as CFC-11, trichlorofluoromethane, and CFC-12, dichlorodifluoromethane, used as refrigerants) and all those molecules regarded as atmospheric pollutants. [Pg.379]

Some halogen compounds have been too reactive for the health of people and the planet. They can destroy healthy cells and attack the Earths atmosphere in the same active way that they kill germs or break down wood into paper. For instance, chlorofluorocarbon (or CFC) compounds used to be popular cooling chemicals in refrigerators and air conditioners and in the gas that pushed hairspray and deodorant out of aerosol cans. CFCs are now widely banned because they destroy Earths atmosphere. Chlorine is also part of the insect killer DDT, a dry cleaning fluid, and the compounds called PCBs. All of these products are now banned or used rarely because they have been linked to pollution and health problems like cancer and liver disease. [Pg.81]

A number of compressed and liquified gases are used as refrigerants and aerosol propellants. These include nitrous oxide, nitrogen, carbon dioxide, propane, and butane. The use of chlorofluorocarbons (CFCs) is restricted because of environmental pollution leading to health hazards. These have been replaced by hydrogenated fluorocarbons (HFCs), which are less likely to cause environmental pollution. [Pg.307]

States would spend 160 billion per year on pollution control. In 1996 Ben Lieberman, an environmental research associate with the Competitive Enterprise Institute, estimated that in the United States the cost of the phaseout of chlorofluorocarbons (CFCs) in accordance with the 1987 Montreal Protocol on Substances That Deplete the Ozone Layer could reach 100 billion over the next ten years. Indeed chemical manufacturers had to develop eco-friendly substitutes such as hydrochlorofluorocarbon (HCFC) and hydro-fluorocarbon (HFC), which are more costly to make, and hundreds of millions of pieces of air-conditioning and refrigeration equipment using CFCs had to be discarded. [Pg.41]

Absorption of ultraviolet radiation by O3 causes it to decompose to O2. In the upper atmosphere, therefore, a steady-state concentration of ozone is achieved, a concentration ordinarily sufficient to provide significant ultraviolet protection of the Earth s surface. However, pollutants in the upper atmosphere such as nitrogen oxides (some of which occur in trace amounts naturally) from high-flying aircraft and chlorine atoms from photolytic decomposition of chlorofluorocarbons (from aerosols, refrigerants, and other sources) catalyze the decomposition of ozone. The overall processes governing the concentration of ozone in the atmosphere are extremely complex. The following reactions can be studied in the laboratory and are examples of the processes believed to be involved in the atmosphere ... [Pg.281]

It is important to know whether molecules being released in the lower atmosphere can reach the stratosphere and affect the amount of ozone in it. Certain types of air pollution give rise to radicals that catalyze ozone depletion. A radical is a chemical species that contains an odd (unpaired) electron, and it is usually formed by the rupture of a covalent bond to form a pair of neutral species. One pressing concern involves chlorofluorocarbons (CFCs)—compounds of chlorine, fluorine, and carbon used as refrigerants and as propellants in some aerosol sprays. CFCs are nonreactive at sea level but can photodissociate in the stratosphere ... [Pg.847]

Air pollution is caused by the domestic and industrial burning of carbonaceous fuels, by industrial processes, and by gases in car exhausts. Among recent problems are industrial emissions of sulfur(IV) oxide, a cause of acid rain, and emissions of chlorofluorocarbons (CFCs), previously widely used in refrigeration, aerosols, etc., and linked to the depletion of ozone in the stratosphere. Carbon dioxide, produced by burning fossil fuels, is slowly building up in the atmosphere, which could result in an... [Pg.179]

As has been discovered over the past 40 years, a principal contributor is X = Cl, and the principal source of Cl is chlorofluorocarbon pollutants. These entirely man-made materials, developed as highly efficient refrigerants, aerosol propellants and solvents, are inert in the troposphere. They are either gases or have a high vapour pressure and therefore aU of them, unless deliberately destroyed, find their way into the atmosphere, and being highly stable, they ultimately end up in the stratosphere, where they do become vulnerable to photodecomposition, for example ... [Pg.230]


See other pages where Chlorofluorocarbons refrigerant pollutant is mentioned: [Pg.13]    [Pg.5]    [Pg.841]    [Pg.311]    [Pg.219]    [Pg.182]    [Pg.292]    [Pg.271]    [Pg.49]    [Pg.455]    [Pg.808]    [Pg.106]    [Pg.238]   
See also in sourсe #XX -- [ Pg.160 ]




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Chlorofluorocarbons

Refrigerants, chlorofluorocarbon

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