November 1989<\/p>\n
CONSUMERS’ QUESTIONS AND ANSWERS
\nRefrigerants and the Atmosphere<\/p>\n
This information is provided as a public service by the
\nRefrigeration Service Engineers Society and your heating
\nand air conditioning service contractor. It is intended
\nto provide clear, factual answers to questions about
\nstratospheric ozone depletion, what is being done about
\nit, and how the situation will affect you.<\/p>\n
Q: WHAT IS OZONE?<\/p>\n
Ozone is a gas. It consists of three atoms of oxygen in
\neach molecule; the oxygen we breathe contains two atoms
\nin each molecule. Chemically, oxygen is O2, and ozone
\nis O3. The *ozone layer* consists of ozone in the
\nstratosphere, high above the earth at an altitude of
\nbetween 7 and 28 miles. It is formed by ultraviolet
\nlight from the sun acting on oxygen molecules. The
\nozone layer absorbs and scatters ultraviolet light from
\nthe sun, preventing harmful amounts of ultraviolet from
\nreaching the earth. For this reason, it is often
\nreferred to as the Ozone Shield.<\/p>\n
Q: BUT ISN’T OZONE UNHEALTHFUL?<\/p>\n
Yes, when it occurs in the lower atmosphere where we
\nbreathe it. This is caused by ultraviolet radiation
\nfrom the sun acting on smog and air pollutants on hot
\nSummer days. This situation should not be confused with
\nthe protective ozone layer in the stratosphere. Ozone
\nat ground level is a harmful pollutant; in the
\nstratosphere it is a protective shield.<\/p>\n
WHAT ARE CFCs?<\/p>\n
*chlorofluorocarbon*; chemicals that CFC stands for
\ncontain chlorine, fluorine and carbon, and may contain
\nhydrogen. These chemicals are inexpensive, safe,
\nnon-flammable refrigerants of high thermal efficiency.
\nThey are also used as solvents in cleaning electronic
\nmicrocircuits, and as the blowing agent in manufacturing
\nfoam insulations. There are some other uses, as well.
\nIn many other countries, CFCs are still used as aerosol
\npropellants.<\/p>\n
CFC is the general term often used inaccurately for all
\nthese compounds. It is important to realize that not
\nall *CFCs* are equally suspected of affecting the
\natmosphere. CFCs which contain chlorine but no hydrogen
\n(fully halogenated CFCs) are the real problem. Those
\nwhich contain no chlorine, only fluorine (HFCs), and
\nthose which contain hydrogen along with chlorine
\n(HCFCs), have a far smaller effect, if any at all.<\/p>\n
Q: WHAT DO CFCs DO TO THE OZONE LAYER?<\/p>\n
Certain chlorine-containing refrigerants are so stable
\nthat they do not break down in the lower atmosphere,
\neven a hundred years or more after being released.
\nThese chemicals gradually float up to the stratosphere,
\nwhere the chlorine reacts with ozone, causing it to
\nchange back to oxygen. The chlorine is not used up in
\nthe reaction; each molecule goes on to cause more and
\nmore ozone-to-oxygen reactions.<\/p>\n
Q: ARE THERE OTHER CHEMICALS THAT HAVE THE SAME EFFECT?<\/p>\n
Yes; bromine-containing compounds, such as contained in
\ncertain *halon* fire extinguishers, also have been
\nimplicated in potential ozone depletion. Bromine is
\nchemically related to chlorine.<\/p>\n
Q: WHAT IS THE RESULT?<\/p>\n
Depletion of the ozone layer could result in increased
\nexposure to ultraviolet radiation at some point in the
\nfuture. The best available scientific information
\nindicates that proper action taken now to reduce
\nconsumption of fully halogenated CFCs should avoid
\npossible future effects on humans and the environment.
\nPotential effects include increases in skin cancer and
\ncataracts, inability to resist certain infectious
\ndiseases, decreased yields of agricultural crops, and
\neffects on marine life that is essential to the food
\nchain.<\/p>\n
Q: WHAT IS THE *OZONE HOLE* I’VE READ ABOUT?<\/p>\n
This is a thinning in the ozone layer over Antarctica,
\nwhich occurs during the Antarctic Spring season (Autumn
\nin the Northern Hemisphere). It occurs over the
\nAntarctic continent due to the unique climate caused by
\npowerful circumpolar winds and extremely low
\ntemperatures there; the lowest on earth. This area is
\nbeing carefully monitored for the degree to which ozone
\nthins out, since it has been found to lead to ozone
\ndepletion in other parts of the world, as well.
\nSignificantly reduced ozone levels were detected in
\n1985, and high chlorine levels were found in 1986.
\nInstrumented aircraft flights through this layer
\nindicate that the ozone depletion problem may be more
\nserious than initially thought.<\/p>\n
Q: DIDN’T WE STOP USING CFCs IN SPRAY CANS FOR THIS
\nREASON?<\/p>\n
During the early 1970s, CFCs used as aerosol propellants
\nconstituted over 50% of total CFC consumption in the
\nU.S. Following concerns initially raised by Professor
\nSherwood Rowland and Dr. Mario Molina in 1974, the
\nE.P.A. and the Food and Drug Administration in 1978
\nbanned the use of CFCs as aerosol propellants in all but
\na few essential applications. This use of CFCs was
\nreduced in the U.S. by approximately 95%.
\nUnfortunately, very few other countries followed the
\nU.S. in this ban. Because of the many practical uses of
\nCFCs, their production and use has now surpassed
\npre-1974 levels.<\/p>\n
Q: IS THIS THE SAME AS THE *GREENHOUSE EFFECT*?<\/p>\n
No, but CFCs may be involved in this problem, also. The
\ngreenhouse effect occurs when carbon dioxide (mostly
\nform the burning of fossil fuels; oil, natural gas, and
\ncoal) and other gases (methane, nitrogen, oxides, and
\nothers) build up in the atmosphere. These gases let
\nincoming sunlight and its heat reach the earth, but
\nblock the earth’s heat from radiating into space. This
\nis the way a greenhouse works, and so the name of the
\neffect. As the gases build up, more heat is trapped,
\nand the planet’s temperature rises. Some scientists now
\nfeel that CFCs may also be contributing to this effect.<\/p>\n
Q: WHAT IS BEING DONE TO STOP DEPLETION OF THE OZONE
\nLAYER?<\/p>\n
Scientists from around the world recognize the
\nimportance and severe results of this problem, and
\nrealize that all countries must cooperate to stop
\nerosion of the ozone shield.<\/p>\n
In the Fall on 1987, representative of more than 30
\nnations, meeting in Montreal, Canada, signed an
\nagreement now known as the Montreal Protocol. The U.S.
\nand Canada were included. On August 1, 1988, the U.S.
\nEnvironmental Protection Agency (E.P.A.) enacted the
\nprovisions of this agreement into regulations for the
\nUnited States.<\/p>\n
The Montreal Protocol and the E.P.A. specify that as of
\nJuly 1, 1989, production and consumption of certain CFCs
\nwill be limited to the levels produced and consumed in
\n1986. This actually means a cutback, because use has
\ngrown since that time. In July, 1993, these levels will
\nbe reduced by 20%, and to 50% of 1986 levels in July of
\n1998. Specifically, the chemicals involved are the
\nfully halogenated CFCs 11, 12, 113, 114, and 115.
\nHalons 1211, 1301, and 2402 are also covered, but on a
\ndifferent time schedule. Scientific, technological,
\nand economic concerns are to be reviewed at least every
\nfour years, with the first review in 1990.<\/p>\n
The most recent technical information indicates that
\neven deeper cuts in production and use may be necessary.
\nThe head of the E.P.A. has stated that these chemicals
\nshould be completely eliminated, and some responsible
\nindustry trade groups agree.<\/p>\n
But all is not lost when it comes to our needs for
\nrefrigerants.<\/p>\n
It’s important to remember that only fully halogenated
\nrefrigerants are being phased down. The refrigerant in
\nhome refrigerators, freezers and automotive air
\nconditioning is mostly CFC 12, one of those being
\nregulated. But central home air conditioning typically
\nuses HCFC 22.<\/p>\n
Over a period of time, new appliances can be redesigned
\nto use HCFCs in place of fully halogenated CFCs.
\nManufacturers of electronic microcircuits uses CFCs to
\nclean parts. They are successfully switching to other
\nchemicals.
\nManufacturers of foam insulation use CFCs to produce the
\ninsulating bubbles in the insulation. There are other
\nmethods and chemicals they can used, although these
\nproduce insulation that is less efficient.<\/p>\n
New replacement refrigerators are also being developed,
\nbut these will require years of testing for any toxic
\neffects, to make sure they are safe.<\/p>\n
Q: CAN’T WE JUST SWITCH TO SOME OF THE OTHER
\nREFRIGERANTS?<\/p>\n
Yes, but this is going to take time. HFC and HCFC
\nrefrigerants can replace the CFCs, but the refrigeration
\nand air conditioning equipment has to be redesigned and
\nmanufactured. The existing refrigerant in your
\nrefrigerator, as an example, cannot be simply removed
\nand replaced with one of the other refrigerants, because
\nthe compressor, cooling coil, and other components in
\nthe system were designed for the specific refrigerant
\nbeing used. Different refrigerants have different
\ncharacteristics, which affect the compressor and other
\ncomponents in the system.<\/p>\n
A lubricating oil also has to be developed that will be
\ncompatible with the new HCFCs and HFCs.<\/p>\n
Q: HOW WILL THIS SITUATION AFFECT US?<\/p>\n
As mentioned, insulation can be manufactured using other
\nmethods and chemicals, but the result is less efficient;
\ngreater thicknesses of insulation will have to be used
\nto get the same insulating effect. That will mean
\nrefrigerators and freezers that are either larger on the
\noutside or smaller on the inside. Refrigerated trucks
\ncan not be make larger on the outside, of course, and so
\ncargo capacity will be reduced. Carrying less frozen
\nfood per trip will mean somewhat higher transportation
\ncosts, which may increase some of the prices we pay.<\/p>\n
Necessary changes in the processing of frozen foods may
\nalso result in increased costs.<\/p>\n
Refrigerators, freezers, and other systems using CFC-12
\nthat are redesigned for other refrigerants will probably
\nbe slightly less efficient, using more electricity for
\noperation. They may also be somewhat heavier.<\/p>\n
The price your air conditioning service contractor pays
\nfor refrigerant will increase, as a result of shorter
\nsupplies. To help control these costs and make supplies
\ngo farther, your service technician will take steps to
\nconserve, recover, and re-use refrigerants. It is
\nincreasingly important to find and repair leaks in
\nsystems, rather than just adding more refrigerant
\nperiodically.<\/p>\n
Existing residential appliances and systems should not
\nbecome obsolete nor have to be replaced any sooner.
\nOwners and operators of large commercial air
\nconditioners and refrigeration systems will probably
\nnotice a great many more changes than the homeowner
\nwill.<\/p>\n
The more thoroughly we can prevent the escape of CFCs to
\nthe atmosphere, and the more wisely we can conserve and
\nrecycle these materials, the better we can protect our
\nhealth and that of generations to come, protect the
\nenvironment, and control our overall costs in the long
\nrun.<\/p>\n
This information was copied 12 October 1989 by<\/p>\n
Jerry J. Trantow
\nResearch Scientist
\nJohnson Controls, Inc.
\n507 E. Michigan Street MS-36
\nMilwaukee, Wi 53201<\/p>\n
out of a bulletin from:<\/p>\n
Refrigeration Service Engineers Society
\n1666 Rand Road
\nDes Plaines, Illinois 60016-3552
\nPHONE (312) 297-6464
\nFAX (312) 297-5038<\/p>\n
with permission from Dean Lewis. If you would like an
\noriginal copy send a self-addressed stamped business
\nsize (#10) envelope to RSES requesting a copy of
\n“Consumers’ Question and Answers, Refrigerants and the
\nAtmosphere”. Quantities are also available, call RSES
\nfor details. The original bulletin has several color
\npictures of the ozone hole, chemical reactions, etc.<\/p>\n
[Remaining Text Missing]<\/p>\n
