GreenVitals

One of the biggest areas of concern to our planet is the diminishment of the ozone layer. The Upper Midwest Aerospace Consortium has described this layer as a special form of oxygen that has three oxygen atoms arranged in a molecule and denoted as O3.

Graphic courtesy of www.eduspace.esa.int.

A crucial property of O3 is the ability to absorb ultraviolet rays at high altitudes (the stratosphere between six-to-25 miles or 10-to-40 kilometers above the sea level) from reaching the Earth’s surface, where excessive levels can have a destructive affect on organic matter.

“For humans, excessive UV exposure spells out increased risk of cancer and cataracts,” says the UMAC, a group comprised of academia, industry, and government agencies connected with NASA and the EROS Data Center at the U.S. Geological Survey.

The U.S. Environmental Protection Agency agrees with the findings attributed to human health effects, saying that, “Less protection from UV light will, over time, lead to higher skin cancer and cataracts rates and crop damage. The U.S., in cooperation with 190 other countries, is phasing out the production of ozone-depleting substances in an effort to safeguard the ozone layer.”

So regardless of all the political bickering continuing to go on in Copenhagen about who will cut emissions by what percentage and how much it will cost, some changes in the U.S. did become law last week.

The EPA signed two rules that will reduce the availability and use hydrochlorofluorocarbons (HCFCs), which are primarily used as refrigerants and harm the ozone layer.

Graphic courtesy of www.eduspace.esa.int.

The EPA and UMAC both agree that in the lower atmosphere, CFCs are stable, nonflammable, low in toxicity, and inexpensive to produce. The problem occurs when they rise to higher altitudes.

The UMAC explains that in the stratosphere, high-energy radiation breaks apart CFCs, releasing an abundance of chlorine at that level. Scientists in both camps agree that one chlorine atom can destroy over 100,000 ozone molecules.

The ozone layer does replenish, but according to scientists, prior to the last decade, it was being depleted faster than it could rebuild itself. Measures taken over the last 10 years, notably steps under the Montreal Protocol, have had the effect of lowering ozone-depleting emissions.

In the EPA’s two latest moves to lower these emissions, the agency in its first rule will prohibit the use of HCFC-22 (also known as R-22) and HCFC-142b in the manufacturing of new air conditioning and refrigeration equipment, beginning on January 1, 2010.

In addition, the second rule will prohibit the sale, distribution, and import of air conditioning and refrigeration appliances and components containing both of these HCFCs that are manufactured after the January 1, 2010 date. All such appliances that were manufactured before this date are legal for sale in the U.S.

The EPA is providing an exception to the allocation rule that allows virgin HCFC-22 to be used in the onsite ‘manufacture’ of appliances for projects between January 1, 2010 and December 32, 2011, if the components have been specified for use at a project under a building permit or contract dated before January 1, 2010.

In addition, under the allocation rule, HCFC-22 produced prior to January 1, 2010, may be used until January 1, 2015, for the manufacture of thermostatic expansion valves (TXVs) and medical equipment.

Through its Significant New Alternatives Policy (SNAP) Program, EPA has found acceptable a number of alternatives to HCFC-22 that do not deplete the ozone layer. R-410A, an HFC refrigerant blend, is the most common. Some common trade names for R-410A include GENETRON AZ-20®, SUVA 410A®, Forane® 410A, and Puron®. EPA maintains a full list of acceptable substitutes for household and light commercial air-conditioning.

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