Environmental Advantages of Ammonia Refrigeration

What are the overall advantages of using ammonia as a refrigerant?
As a refrigerant, ammonia offers three distinct advantages over other commonly used industrial refrigerants. First, ammonia is environmentally compatible. It does not deplete the ozone layer and does not contribute to global warming. Second, ammonia has superior thermodynamic qualities, as result ammonia refrigeration systems use less electricity. Third, ammonia's recognizable odor is it's greatest safety asset. Unlike most other industrial refrigerants that have no odor, ammonia refrigeration has a proven safety record in part because leaks are not likely to escape detection.
Does ammonia harm the ozone layer?
No. Ammonia does not harm atmospheric ozone. Ammonia is a natural refrigerant. It is not a halocarbon like many of the synthetic refrigerants on the market. When halocarbons are released into the atmosphere, they eventually reach the stratosphere and the ozone layer. Halocarbons are extremely stable chemically with estimated life cycles of two to three centuries. When released into the atmosphere, this stability allows halocarbons to migrate through the troposphere and into the stratosphere. At this altitude, the intense ultraviolet rays of the sun break down halocarbon molecules, releasing chlorine ions, which in turn act as catalysts to break down ozone molecules. This process reduces the ozone layer's effectiveness as a filter against ultraviolet radiation, resulting in higher amounts of ultraviolet radiation reaching the surface of the earth with harmful biological consequences. Increased radiation causes increased health risks in humans and damages the flora and fauna of the ecosystem.
Does Ammonia contribute to Global warming?
No. Just as ammonia does not damage atmospheric ozone, ammonia, with a life cycle in the atmosphere of less than one week, does not contribute to the greenhouse effect responsible for global warming. Global warming results from the short wave, near infra-red radiation that reaches the earth from the sun. About fifty percent of the sun's radiation reaches the earth. This is absorbed by the earth's surface which re-emits the radiation in longer, far infra-red wavelengths. This re-emitted radiation is partially absorbed by gasses known as greenhouse gasses. Greenhouse gasses are either natural (CO2, water vapor, etc.) or man-made (CO2, N2O, CH4, CFC, HCFC, HFC, etc.).
Is ammonia a potential substitute for refrigerants that contribute to global warming and the erosion of the ozone layer?
The Clean Air Act Amendments of 1990 gave statutory recognition to the Montreal Protocol's phase-outs in the United States and established a comprehensive set of regulatory requirements for recovery, recycling, and disposal of CFCs when equipment containing them is serviced or discarded. Part of the regulations established a U.S. EPA program for the control or phase-out of substances harmful to the stratospheric ozone layer. Through the Significant New Alternatives Policy (SNAP) program, the agency identified ammonia as an acceptable substitute to ozone depleting substances in the major industrial sectors, including refrigeration and air conditioning.