CONSUMERS' QUESTIONS AND ANSWERS
 Refrigerants and the Atmosphere
 
 This information is provided as a public service by the 
 Refrigeration Service Engineers Society and your heating 
 and air conditioning service contractor.  It is intended 
 to provide clear, factual answers to questions about 
 stratospheric ozone depletion, what is being done about 
 it, and how the situation will affect you.
 
 Q:  WHAT IS OZONE?
 
 Ozone is a gas.  It consists of three atoms of oxygen in 
 each molecule; the oxygen we breathe contains two atoms 
 in each molecule.  Chemically, oxygen is O2, and ozone 
 is O3.  The ozone layer consists of ozone in the 
 stratosphere, high above the earth at an altitude of 
 between 7 and 28 miles.  It is formed by ultraviolet 
 light from the sun acting on oxygen molecules.  The 
 ozone layer absorbs and scatters ultraviolet light from 
 the sun, preventing harmful amounts of ultraviolet from 
 reaching the earth.  For this reason, it is often 
 referred to as the Ozone Shield.
 
 Q:  BUT ISN'T OZONE UNHEALTHFUL?
 
 Yes, when it occurs in the lower atmosphere where we 
 breathe it.  This is caused by ultraviolet radiation 
 from the sun acting on smog and air pollutants on hot 
 Summer days.  This situation should not be confused with 
 the protective ozone layer in the stratosphere.  Ozone 
 at ground level is a harmful pollutant; in the 
 stratosphere it is a protective shield.
 
 WHAT ARE CFCs?
 
 CFC stands for chlorofluorocarbon; chemicals that 
 contain chlorine, fluorine and carbon, and may contain 
 hydrogen.  These chemicals are inexpensive, safe, 
 non-flammable refrigerants of high thermal efficiency. 
 They are also used as solvents in cleaning electronic 
 microcircuits, and as the blowing agent in manufacturing 
 foam insulations.  There are some other uses, as well. 
 In many other countries, CFCs are still used as aerosol 
 propellants.
 
 CFC is the general term often used inaccurately for all 
 these compounds.  It is important to realize that not 
 all CFCs are equally suspected of affecting the 
 atmosphere.  CFCs which contain chlorine but no hydrogen 
 (fully halogenated CFCs) are the real problem.  Those 
 which contain no chlorine, only fluorine (HFCs), and 
 those which contain hydrogen along with chlorine 
 (HCFCs), have a far smaller effect, if any at all.
 
 Q:  WHAT DO CFCs DO TO THE OZONE LAYER?
 
 Certain chlorine-containing refrigerants are so stable 
 that they do not break down in the lower atmosphere, 
 even a hundred years or more after being released. 
 These chemicals gradually float up to the stratosphere, 
 where the chlorine reacts with ozone, causing it to 
 change back to oxygen.  The chlorine is not used up in 
 the reaction; each molecule goes on to cause more and 
 more ozone-to-oxygen reactions.
 
 Q:  ARE THERE OTHER CHEMICALS THAT HAVE THE SAME EFFECT?
 
 Yes; bromine-containing compounds, such as contained in 
 certain Halon fire extinguishers, also have been 
 implicated in potential ozone depletion.  Bromine is 
 chemically related to chlorine.
 
 Q:  WHAT IS THE RESULT?
 
 Depletion of the ozone layer could result in increased 
 exposure to ultraviolet radiation at some point in the 
 future.  The best available scientific information 
 indicates that proper action taken now to reduce 
 consumption of fully halogenated CFCs should avoid 
 possible future effects on humans and the environment. 
 Potential effects include increases in skin cancer and 
 cataracts, inability to resist certain infectious 
 diseases, decreased yields of agricultural crops, and 
 effects on marine life that is essential to the food 
 chain.
 
 Q:  WHAT IS THE OZONE HOLE I'VE READ ABOUT?
 
 This is a thinning in the ozone layer over Antarctica, 
 which occurs during the Antarctic Spring season (Autumn 
 in the Northern Hemisphere).  It occurs over the 
 Antarctic continent due to the unique climate caused by 
 powerful circumpolar winds and extremely low 
 temperatures there; the lowest on earth.  This area is 
 being carefully monitored for the degree to which ozone 
 thins out, since it has been found to lead to ozone 
 depletion in other parts of the world, as well. 
 Significantly reduced ozone levels were detected in 
 1985, and high chlorine levels were found in 1986. 
 Instrumented aircraft flights through this layer 
 indicate that the ozone depletion problem may be more 
 serious than initially thought.
 
 Q:  DIDN'T WE STOP USING CFCs IN SPRAY CANS FOR THIS 
 REASON?
 
 During the early 1970s, CFCs used as aerosol propellants 
 constituted over 50% of total CFC consumption in the 
 U.S.  Following concerns initially raised by Professor 
 Sherwood Rowland and Dr. Mario Molina in 1974, the 
 E.P.A. and the Food and Drug Administration in 1978 
 banned the use of CFCs as aerosol propellants in all but 
 a few essential applications.  This use of CFCs was 
 reduced in the U.S. by approximately 95%. 
 Unfortunately, very few other countries followed the 
 U.S. in this ban.  Because of the many practical uses of 
 CFCs, their production and use has now surpassed 
 pre-1974 levels.
 
 Q:  IS THIS THE SAME AS THE GREENHOUSE EFFECT?
 
 No, but CFCs may be involved in this problem, also.  The 
 greenhouse effect occurs when carbon dioxide (mostly 
 form the burning of fossil fuels; oil, natural gas, and 
 coal) and other gases (methane, nitrogen, oxides, and 
 others) build up in the atmosphere.  These gases let 
 incoming sunlight and its heat reach the earth, but 
 block the earth's heat from radiating into space.  This 
 is the way a greenhouse works, and so the name of the 
 effect.  As the gases build up, more heat is trapped, 
 and the planets temperature rises.  Some scientists now 
 feel that CFCs may also be contributing to this effect.
 
 Q:  WHAT IS BEING DONE TO STOP DEPLETION OF THE OZONE 
 LAYER?
 
 Scientists from around the world recognize the 
 importance and severe results of this problem, and 
 realize that all countries must cooperate to stop 
 erosion of the ozone shield.
 
 In the Fall on 1987, representative of more than 30 
 nations, meeting in Montreal, Canada, signed an 
 agreement now known as the Montreal Protocol.  The U.S. 
 and Canada were included.  On August 1, 1988, the U.S. 
 Environmental Protection Agency (E.P.A.) enacted the 
 provisions of this agreement into regulations for the 
 United States.
 
 The Montreal Protocol and the E.P.A. specify that as of 
 July 1, 1989, production and consumption of certain CFCs 
 will be limited to the levels produced and consumed in 
 1986.  This actually means a cutback, because use has 
 grown since that time.  In July, 1993, these levels will 
 be reduced by 20%, and to 50% of 1986 levels in July of 
 1998.  Specifically, the chemicals involved are the 
 fully halogenated CFCs 11, 12, 113, 114, and 115. 
 Halons 1211, 1301, and 2402 are also covered, but on a 
 different  time schedule.  Scientific, technological, 
 and economic concerns are to be reviewed at least every 
 four years, with the first review in 1990.
 
 The most recent technical information indicates that 
 even deeper cuts in production and use may be necessary. 
 The head of the E.P.A. has stated that these chemicals 
 should be completely eliminated, and some responsible 
 industry trade groups agree.
 
 But all is not lost when it comes to our needs for 
 refrigerants.
 
 It's important to remember that only fully halogenated 
 refrigerants are being phased down.  The refrigerant in 
 home refrigerators, freezers and automotive air 
 conditioning is mostly CFC 12, one of those being 
 regulated.  But central home air conditioning typically 
 uses HCFC 22.
 
 Over a period of time, new appliances can be redesigned 
 to use HCFCs in place of fully halogenated CFCs. 
 Manufacturers of electronic microcircuits uses CFCs to 
 clean parts.  They are successfully switching to other 
 chemicals.
 Manufacturers of foam insulation use CFCs to produce the 
 insulating bubbles in the insulation.  There are other 
 methods and chemicals they can used, although these 
 produce insulation that is less efficient.
 
 New replacement refrigerators are also being developed, 
 but these will require years of testing for any toxic 
 effects, to make sure they are safe.
 
 Q:  CAN'T WE JUST SWITCH TO SOME OF THE OTHER 
 REFRIGERANTS?
 
 Yes, but this is going to take time.  HFC and HCFC 
 refrigerants can replace the CFCs, but the refrigeration 
 and air conditioning equipment has to be redesigned and 
 manufactured.  The existing refrigerant in your 
 refrigerator, as an example, cannot be simply removed 
 and replaced with one of the other refrigerants, because 
 the compressor, cooling coil, and other components in 
 the system were designed for the specific refrigerant 
 being used.  Different refrigerants have different 
 characteristics, which affect the compressor and other 
 components in the system.
 
 A lubricating oil also has to be developed that will be 
 compatible with the new HCFCs and HFCs.
 
 Q: HOW WILL THIS SITUATION AFFECT US?
 
 As mentioned, insulation can be manufactured using other 
 methods and chemicals, but the result is less efficient; 
 greater thicknesses of insulation will have to be used 
 to get the same insulating effect.  That will mean 
 refrigerators and freezers that are either larger on the 
 outside or smaller on the inside.  Refrigerated trucks 
 can not be make larger on the outside, of course, and so 
 cargo capacity will be reduced.  Carrying less frozen 
 food per trip will mean somewhat higher transportation 
 costs, which may increase some of the prices we pay.
 
 Necessary changes in the processing of frozen foods may 
 also result in increased costs.
 
 Refrigerators, freezers, and other systems using CFC-12 
 that are redesigned for other refrigerants will probably 
 be slightly less efficient, using more electricity for 
 operation.  They may also be somewhat heavier.
 
 The price your air conditioning service contractor pays 
 for refrigerant will increase, as a result of shorter 
 supplies.  To help control these costs and make supplies 
 go farther, your service technician will take steps to 
 conserve, recover, and re-use refrigerants.  It is 
 increasingly important to find and repair leaks in 
 systems, rather than just adding more refrigerant 
 periodically.
 
 Existing residential appliances and systems should not 
 become obsolete nor have to be replaced any sooner. 
 Owners and operators of large commercial air 
 conditioners and refrigeration systems will probably 
 notice a great many more changes than the homeowner 
 will.
 
 The more thoroughly we can prevent the escape of CFCs to 
 the atmosphere, and the more wisely we can conserve and 
 recycle these materials, the better we can protect our 
 health and that of generations to come, protect the 
 environment, and control our overall costs in the long 
 run.
 
 This information was copied 12 October 1989 by
 
 Jerry J. Trantow
 Research Scientist
 Johnson Controls, Inc.
 507 E. Michigan Street  MS-36
 Milwaukee, Wi 53201
 
 out of a bulletin from:
 
 Refrigeration Service Engineers Society
 1666 Rand Road
 Des Plaines, Illinois 60016-3552
 PHONE (312) 297-6464
 FAX (312) 297-5038
 
 with permission from Dean Lewis.  If you would like an 
 original copy send a self-addressed stamped business 
 size (#10) envelope to RSES requesting a copy of 
 "Consumers' Question and Answers, Refrigerants and the 
 Atmosphere".  Quantities are also available, call RSES 
 for details.  The original bulletin has several color 
 pictures of the ozone hole, chemical reactions, etc.
 
 Taken from the PSA BBS, in Milwaukee (414-278-5390).