Monday, September 3, 2007

Ozone!!!

16th September - World Ozone Day


Stratospheric ozone (sometimes referred to as "good ozone") plays a beneficial role by absorbing most of the biologically damaging ultraviolet sunlight (called UV-B), allowing only a small amount to reach the Earth's surface. The absorption of ultraviolet radiation by ozone creates a source of heat, which actually forms the stratosphere itself (a region in which the temperature rises as one goes to higher altitudes). Ozone thus plays a key role in the temperature structure of the Earth's atmosphere. Without the filtering action of the ozone layer, more of the Sun's UV-B radiation would penetrate the atmosphere and would reach the Earth's surface. Many experimental studies of plants and animals and clinical studies of humans have shown the harmful effects of excessive exposure to UV-B radiation.



What Can I Do to Protect the Ozone Layer?

Car Air Conditioner Tips
Go only to service facilities with EPA-certified technicians

Make sure refrigerants from your vehicle will be recovered and recycled during servicing

Repair all leaks in the a/c system (not required by federal law, but helpful in protecting the ozone layer)
Although not required by federal law, this is one of the single best ways to do your part to protect the ozone layer. About 20-30 million cars on the road today use CFC refrigerants in their air-conditioning (AC) systems. If leaky systems were repaired, it would prevent the release of millions of pounds of CFCs into the atmosphere each year.

If your air conditioner needs major repairs, talk to your certified service professional about having it converted to use an alternative refrigerant.

Home Appliance Tips

Repair air conditioners
Although not required by federal law, this step prevents ozone-depleting refrigerants from escaping. Make certain the refrigerant is recovered before servicing. See a fact sheet on this topic.

If you purchase a new A/C system or heat pump, purchase one that uses non-ozone-depleting refrigerant. See a fact sheet on this topic.

Remove the refrigerant from refrigerators, air conditioners, and dehumidifiers before disposing of them
Removing the refrigerant before disposal of old refrigerators alone would prevent the release of about 4 million pounds of CFCs each year. The used refrigerant can be recycled and reused. Ask your local government or waste hauler if the refrigerant will be removed before the appliance is discarded.

Make sure your service technician is EPA certified.

Work with local officials
Help start a refrigerant recovery and recycling program in your area if none exists. Not only will a responsible appliance disposal help to protect the ozone layer, but the recovered CFC-12 from appliances can be resold, helping to recoup a portion of the costs of the program.

The SNAP program has reviewed substitutes for the following industrial sectors:

Refrigeration & Air Conditioning
end-uses typically use a refrigerant in a vapor compression cycle to cool and/or dehumidify a substances or space, like a refrigerator cabinet, room, office building, or warehouse.
Foam Blowing Agents
encompasses a wide variety of applications including refrigerators buildings, automobiles, furniture, packaging and many more. The blowing agent, which was typically an ODS, is used to propel liquid plastic resin, and in the case of foam used for insulation, functions as an insulating component of the foam.
Cleaning Solvents
are used to remove oil, grease, solder flux, and other contaminants.
Fire Suppression and Explosion Protection
have used halons in many applications because they are electrically non-conductive, dissipate rapidly without residue, are safe for limited human exposure, and are extremely efficient in extinguishing most types of fires. Because of their strong ozone depletion potential, the Montreal Protocol required the earliest production and import phaseout of halons in the U.S. in 1994.
Aerosols
are substances stored under pressure and then released as a suspension of particles in air.
Sterilants
kill microorganisms on medical equipment and devices. SNAP has identified alternatives to blends of 88% CFC-12 and 12% ethylene oxide, known as "12/88." In that blend, ethylene oxide sterilizes the equipment and CFC-12 is a dilutent solvent to form a non-flammable blend.
Tobacco Expansion
is the process of puffing leaves of tobacco to decrease the volume of tobacco used in cigarette production. SNAP has identified alternatives to CFC-11 for tobacco expansion.
Adhesives, Coatings & Inks
traditionally contain solid components that are suspended in a solvent, spread over a surface and bond to it, and then allow the solvent to evaporate. Prior to the Montreal Protocol, the ozone-depleting substance methyl chloroform was often used as the carrier solvent in adhesives, coatings, and inks.

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