In 1990 Congress passed the Clean Air Act to help improve the quality of the air we breathe. The law addresses many sources and types of air pollution, including auto emissions, factory releases and ozone-depleting gases such as chloroflourocarbons (CFC's), hydrochloroflourocarbons (HCFC's) and hydroflourocarbons (HFC's). These gases are commonly used as refrigerants in air conditioners, dehumidifiers, freezers and refrigerators. They cause little harm when contained in appliances, but scientists fear that they may contribute to the growing depletion of the earth's ozone layer when
released into the atmosphere. The ozone layer blocks many of the sun's ultraviolet rays. "Holes" in the ozone layer are blamed for increased incidence of skin cancer and eye problems such as cataracts.
In an effort to control the release of refrigerants gases, Section 608 of the Clean Air Act addresses the problem of recycling the gases contained in home appliances such as freezers, refrigerators and air conditioning units. This section of the law, part of which took effect on July 1, 1992, requires anyone disposing of these appliances to follow an extensive compliance program. The fact that part of the law is in effect while the rules for the program have not yet been developed is causing confusion among people wishing to dispose of an appliance and businesses who haul or recycle them.
The law prohibits anyone from "knowingly venting ozone depleting compounds used as refrigerants into the atmosphere while maintaining, servicing, repairing, or disposing of air conditioning or refrigeration equipment." Violators can be fined up to $25,000 a day for non-compliance. It also requires the U.S. Environmental Protection Agency (USEPA) to develop a program of certification for both technicians who work on appliances that contain refrigerant gases and equipment used to drain the gases from appliances prior to disposal. Unfortunately, those programs were not in place when the July 1 venting ban took effect, and therein lies the confusion.
The current USEPA-planned proposal calls for the items that typically enter the waste stream with their refrigeration units intact (freezers, etc.) to be subject to special disposal rules. In these cases, the person who is the final handler of the appliance (i.e., scrap metal dealer) is responsible for ensuring that the refrigerant gases have been recovered.
The process used to recover the refrigerant gases varies depending on the type of appliance. Usually, a special metal recovery tank with a vacuum hose is used to remove the gases from the appliance. When full, the tank is taken to a centralized collection point and eventually transported to a reclaimer who processes the used refrigerant to near-virgin quality or a minmum of 99.5% purity prior to being available for resale. The sale of product less than the required minimum is illegal, and can only be returned to the system from which it was recovered or sent for destruction. Ninety-five percent of the gases are separated, reblended and used as reclaimed refrigerant. The other five percent is water and oil.
Because the law is new and major portions of the rules have not been adopted, many waste haulers and scrap metal recyclers are hesitant to accept appliances with refrigerants. Those who do accept the appliances are likely to charge a fee for removing the refrigerant (usually $15-$60). Businesses that do not have reclaiming equipment are likely to accept these appliances only with certification that the gases have been properly removed. CFC Reclamation and Recycling Service offers a disposal program locally in the Big Country and surrounding Abilene, Texas area. Individuals who try to circumvent the law by venting the gases without proper equipment and training are themselves liable for the $25,000 fine. Beyond the vening of the gas, the law requires that the compressor and system be drained of the CFC bearing oils.
In the long run, recapturing refrigerant gases should help prevent increased destruction of the earth's ozone layer. As rules for the program are developed, disposal of appliances with refrigerant gases should become much easier. Until that happens, citizens should contact their local waste hauler, recycler or appliance store for information on disposal programs in their area. For more information on the Clean Air Act, contact the Stratospheric Ozone Protection Bureau of the U.S. Environmental
Protection Agency at 1-800-2961996.
Some areas of the country have implemented a "Second Refrigerator Pickup" program designed to remove old, less energy-efficient second refrigerators or freezers. Many of these programs are free-of-charge, however, the new law is causing some cities to rethink this policy. Contact your local utility to see if such a program is available.
Ozonesphere - Region in the upper atmosphere between about 10 and 50 km (6 and 30 miles) also be easily destroyed by solar ultraviolet radiation of wavelengths less than 300 nanometres.
Because of the strong absorption of solar ultraviolet radiation by molecular oxygen and ozone, solar radiation capable of producing ozone cannot reach the lower levels of the atmosphere, and the photochemical production of ozone is not significant below about 20 km. This absorption of solar energy is very important in producing a temperature maximum at about 50 km, called the stratopause, or the mesopeak. Also, the presence of the ozone layer in the upper atmosphere, with its accompanying absorption, effectively blocks almost all solar radiation of wavelengths less than 290 nanometres from reaching the Earth's surface, where it would injure or kill most living things.
Certain air pollutants, particularly chlorofluorocarbons, halons (chlorofluorobromine compounds), and nitrogen oxides, can diffuse into the ozonosphere and destroy ozone. (See chlorofluorocarbon.) In the mid-1980s scientists discovered that a "hole" developed periodically in the ozonosphere above
Antarctica; it was found that the ozone layer there was thinned by as much as 40-50 percent from its normal concentrations. This severe regional ozone depletion was explained as a natural phenomenon, but one that was probably exacerbated by the effects of chlorofluorocarbons and halons. Concern over increasing global ozone depletion led to international restrictions on the use chlorofluorocarbons and halons, to scheduled reductions in their manufacture, and to regulation of the permissible amount of nitrogen oxides in automobile exhaust gases.
|Even though the ozone layer is about 40 km thick, the total amount of ozone, compared with more abundant atmospheric gases, is quite small. If all of the ozone in a vertical column reaching up through the atmosphere were compressed to sea-level pressure, it would form a layer only a few millimetres thick.|