This refrigerant was made with a few types of chlorofluorocarbons or CFCs. Freons are colorless, nonflammable, have no odor and offer a non-corrosive gas or liquid. They are a mix of aliphatic compounds with halogens, fluorine, and carbon. They represent a very stable product that could be placed in a spray container and was commercialized under the name of Freon. This invention came about as a safer alternative to an earlier sulfur dioxide and ammonia refrigerant that could easily become dangerous and flammable.
These compounds offered a viable way of making refrigerant products that were non-flammable, and they were first created in the late s and were marketed as a non-toxic, non-flammable refrigerant and were first marketed by the DuPont company. The first of the compounds were known as CFC It contained one carbon and two chlorides with two fluorines CFC or F are halogenated hydrocarbons with dichlorodifluoromethane and were used as an aerosol spray propellants, refrigerants, foam blowing products and other similar solvents.
They were used in many refrigerant or insulating processes because the were non-toxic and could easily be converted to a liquid or gas to be used later in vehicles and home products.
Chlorofluorocarbons are not toxic and not harmful to human beings. They contain carbon atoms, chlorine atoms and fluorine atoms. Studies conducted in the s found that CFCs when released into the atmosphere a common occurrence in cars, and refrigerant equipment , they caused a significant deterioration of the ozone layer in the atmosphere.
This is important because the ozone layer protects human skin and many living organisms from ultraviolet rays emitted from the sun. CFC components have a life cycle in the atmosphere of up to years. So one free chlorine atom coming from a CFC molecule can cause a huge amount of damage and destroy ozone molecules for many years.
Use of HFCs in mobile air conditioning will end with Model Year , while prohibitions on HFC use in new fire suppression systems, cold storage, residential refrigeration, and building chillers go into place on January 1 of , , and , respectively.
In addition to the various production bans, servicers and disposers of appliances and motor vehicle air conditioners are required to obtain technician certification, proper refrigerant recovery or recycling equipment, and keep records.
Skip to main content. Air How's the air? Ozone depletion Man-made compounds such as chlorofluorocarbons CFCs , hydrofluorocarbons HCFCs and halons destroy ozone in the upper atmosphere stratosphere. Stratospheric ozone loss can result in potential harm to human health and the environment, including: increased incidence of skin cancer and cataracts immune system system damage damage to terrestrial and aquatic plant life increased formation of ground-level ozone smog Most stratospheric ozone depletion is caused when chlorine or bromine reacts with ozone.
Climate change While acting to destroy ozone, CFCs and HCFCs also act to trap heat in the lower atmosphere, causing the earth to warm and climate and weather to change. Their chemistry was difficult to replicate in the laboratory. Additionally, stratospheric ozone concentrations fluctuate naturally by geography and by season.
The stratosphere is not an easy place to do research in. Measurements of ozone concentration were carried out by instruments carried into the stratosphere by balloons and aircraft.
Ozone was also measured by instruments on satellites orbiting Earth, though satellite technology in the mids was still rather primitive. The crucial evidence supporting the CFC hypothesis came from British scientists working at the Halley Bay Station of the British Antarctic Survey, who had been taking ground-based measurements of total ozone for decades. In , Joseph C. Farman and his colleagues at BAS studied the raw data and found that stratospheric ozone had decreased greatly since the s.
The Antarctic ozone hole, as it came to be known, made depletion of the ozone layer a real and present danger to lawmakers and the public at large.
Predictions of significant increases in the incidence of skin cancer resulting from continued use of CFCs spurred international action. In , 56 countries agreed under what became known as the Montreal Protocol to cut CFC production and use in half. In subsequent years, the protocol was strengthened to require an eventual worldwide phaseout of the production of CFCs and other ozone depleting chemicals.
It is a global problem. What is important is that it led to an international agreement that solved the problem. Their unprecedented advocacy ultimately led to the phasing out of CFCs worldwide through the passage of the Montreal Protocol in The research of Rowland and Molina brought worldwide attention to the impact of human-contributed pollution on a planetary scale.
Their work was among the first to directly effect a global shift in policy, preceding the current debate on climate change. ACS designated F. The commemorative plaque reads:.
At the University of California, Irvine, F. When the scientists reported their findings in , CFCs were widely used as refrigerant gases and as propellants in aerosol sprays. Rowland and Molina convinced skeptical industrialists, policymakers, and the public of the danger of CFCs. Chlorofluorocarbons and Ozone Depletion. Back to Landmarks Main Page. Learn more: About the Landmarks Program. Landmarks Lesson Plans. Careers Launch and grow your career with career services and resources.
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