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Depletion of the Stratospheric Ozone Layer: October 1997 Air Resources Branch BC Environment The Science, Impacts and Mitigation Measures

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Page 1: Depletion of the Stratospheric Ozone LayerDepletion of the Stratospheric Ozone Layer: The Science, Impacts and Mitigation Measures "The "boundless" blue sky . . .which gives us breath

Depletion of the

Stratospheric Ozone Layer:

October 1997

Air Resources Branch

BC Environment

The Science, Impacts and Mitigation Measures

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FOR MORE INFORMATION

If you would like more information aboutstratospheric ozone depletion or other air qualityissues, contact:

Air Resources BranchBC EnvironmentP.O. Box 9341Stn Provincial GovtVictoria, B.C.V8W 9M1

Phone: (250) 387-9933Fax: (250) 356-7197Internet: http://www.env.gov.bc.ca

To find out more about the health effects of UVradiation, and how to protect yourself and yourfamily, ask your local health unit or departmentfor copies of Health Files #11 (Ultraviolet Light)and #26 (“Sun-Smart" Your Kids).

Canadian Cataloguing in Publication DataMain entry under title:Depletion of the stratospheric ozone layer

Includes bibliographical references: p.ISBN 0-7726-3455-6

1. Ozone layer depletion - British Columbia. I. BC Environment. AirResources Branch.

TD885.5.085D46 1998 363.73'926'09711 C98-960017-3

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Contents

1. Introduction............................................................................................................................... 1

2. Background ............................................................................................................................... 1

3. Stratospheric Ozone Depletion.................................................................................................. 2

4. What Causes Ozone Depletion? ................................................................................................ 4British Columbia’s ODS Emissions ............................................................................................. 5

5. The Impacts of Ozone Depletion ............................................................................................... 6Human Beings ............................................................................................................................ 6Plants and Animals ..................................................................................................................... 6Materials .................................................................................................................................... 7

6. Protecting the Ozone Layer: A Global Effort........................................................................... 7The Vienna Convention for the Protection of the Ozone Layer .................................................... 7The Montreal Protocol on Substances that Deplete the Ozone Layer .......................................... 7

7. The Costs and Benefits for Canada of Implementing theMontreal Protocol ..................................................................................................................... 8

8. Canada’s Actions to Stop ODS Emissions ................................................................................ 9Federal Initiatives .................................................................................................................... 9Federal-Provincial Activities ..................................................................................................... 10

9. British Columbia’s Initiatives.................................................................................................. 11Legislation: The Ozone-Depleting Substances (ODS) Regulation .............................................. 11Activities Supporting the ODS Regulation ................................................................................. 11Getting the Word Out................................................................................................................ 12

10. The Challenges Ahead............................................................................................................. 12The Federal Government and the Other Provinces ...................................................................... 12The B.C. Ministry of Environment, Lands and Parks ................................................................. 13

11. Can We Halt Ozone Depletion Before It Is Too Late? ........................................................... 13

Appendices1. Major Ozone-Depleting Substances: Uses and Ozone-Depleting Potential (ODP) ...................... 152. ODS Phaseout Dates under the Montreal Protocol (with amendments), and Canadian

Timetable.................................................................................................................................. 163. Ozone-Depleting Substances Regulation (February 1993) ........................................................ 174. The National Action Plan (June 1997): Priority Tasks................................................................ 185. A Note about Ozone Layer Monitoring in Canada...................................................................... 19

References............................................................................................................................................ 21

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Figures

1. Stratospheric Ozone Reduction over Monitoring Sites across Canada:Percent Departure (averaged) from Normal Levels, Jan. 1 - Dec. 31, 1995................................... 3

2. Stratospheric Ozone Reduction over Monitoring Sites across Canada:Percent Departure (averaged) from Normal Levels, Jan. 1 - June 30, 1997 ................................... 4

3. Reported ODS Emissions in British Columbia, 1990 ................................................................... 5

4. Projected Recovery of the Ozone Layer ..................................................................................... 14

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Depletion of the Stratospheric Ozone Layer:

The Science, Impacts and Mitigation Measures

"The "boundless" blue sky . . .which gives us breath and protects us . . . is but an infinitesimally thin film.How dangerous it is to threaten even the smallest part of this gossamer covering, this conserver of life.”Vladimir Shatalov, cosmonaut

1. IntroductionHumankind’s emissions of halocarbons have caused a serious thinning of the Earth’s natural sunscreen—the ozone layer. Stopping ozone layer depletion is one of the major challenges facing the world today. Forthe ozone layer is truly a conserver of life, essential to the survival of all living things.

This report examines the key issues surrounding ozone depletion: the science, the impacts, and themitigation measures— both those that are already being carried out by governments across the world andthose that should be adopted in the near future. The focus is on British Columbia, especially with respect tocurrent and future mitigation measures.

2. BackgroundOzone (O3), a simple molecule composed of threeoxygen atoms, can be found throughout theatmosphere. However, the greatest concentrationoccurs in the stratosphere, in a fragile band beginningabout 20 kilometres above our planet and reaching upto the 50-kilometre level. Even there, ozone is a raregas, accounting for just one in every 100,000molecules.

In an unpolluted atmosphere, there is a balancebetween the amount of stratospheric ozone beingproduced and destroyed, so the total concentration ofozone remains relatively constant. The ozone layer isnormally thickest over the poles and thinnest aroundthe equator.

Stratospheric ozone filters out most of the sun’sharmful ultraviolet (UV) radiation— specifically,UV-B radiation. A significant decrease in the amountof ozone in the stratosphere could have seriousimplications for human health, and the well-being of allliving creatures and ecosystems.

The Kinds of Ultraviolet RadiationUltraviolet radiation is classified accordingto wavelength. The shortest wavelength isthe most “energetic” and biologicallydangerous.

UV-A (longest wavelength): The leastdamaging form of UV radiation. Most UV-Arays pass right through the ozone layer andreach the Earth.

UV-B: Potentially very harmful. Normally,most of the sun’s UV-B radiation isabsorbed by stratospheric ozone. Butdepletion of the ozone layer will allow moreUV-B to get through to the Earth’s surface.

UV-C (shortest wavelength): The mostdangerous. Fortunately, all UV-C isabsorbed by oxygen and ozone in thestratosphere, and never makes it to thesurface of the planet.

The danger from UV radiation comesmainly from UV-B, although UV-A posessome risk if exposure is long enough.

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3. Stratospheric Ozone DepletionSince the late 1970s, the Earth’s protective ozone layer has beendepleted by about 5% in the mid-latitudes and 11% over theSouth Pole, on average.

Stratospheric ozone depletion is most pronounced over the polarregions— especially Antarctica— due to geoclimatic factors. Butozone depletion now affects most of North America, Europe,Russia, Australia and New Zealand, as well as a sizeable chunkof South America. In both hemispheres, stratospheric ozone ismost reduced during the spring.

Ozone depletion above Antarctica has markedly worsened sincethe late ‘70s— in terms of the amount of ozone lost, as well as thesize and duration of the ozone “hole” (i.e., how far the holeextended over the South Pole and how long it lasted before itclosed up).

In September - October 1995 (the austral spring), the ozoneconcentration over Antarctica declined by an unprecedented 60%.The 1995 depletion was also one of the most rapid and extensiveon record, covering an area twice the size of Europe (20 millionsquare kilometres) at its seasonal peak in October. A similarsituation occurred in 1996, but the central region of the holeexperienced an even greater ozone reduction than it did in 1995.Figures for 1997 are not complete, at the time of this writing.

A dramatic and sustained hole has not yet formed over the Arctic. However, the springtime depletion overthe Canadian Arctic was the lowest ever in March 1997, at 45% below normal. One year before, thedepletion reached 30%— compared to a depletion of 5-10% during the 1980s and early ‘90s. The extremedrop in Arctic ozone concentrations in 1996 and 1997 is believed to be partly due to an unusual pattern ofwinds in the Arctic stratosphere, similar to what is normal for the Antarctic.

Average ozone depletion over southern Canada (below the 60th parallel) is not assevere as over the poles, but it is still of real concern. During Jan. 1 - Dec. 31, 1995,the average ozone thickness above this region was 8% below normal (see figure 1),hitting a low of 13% in the spring of ‘95.

Over southwestern B.C. (Saturna Island monitoring station, near Vancouver), theozone layer was depleted by an average of 8.9% in 1995 (figure 1). As usual, thedepletion was the worst in the spring, falling to almost 15% below normal in thefirst week of April.

The average amount of ozone depletion over southern Canada and B.C. in 1996 is not known because poorweather conditions at many of the country’s monitoring stations hampered data collection. However, theinformation that was collected indicates the 1996 depletion was not nearly as severe as in 1995.

What do these depletionfigures mean for life on earth?Since only ozone can absorbUV-B, a decrease instratospheric ozone is expectedto trigger a (roughly)proportionate rise in UV-Bradiation. For each 1% drop instratospheric ozone levels, about1.2% more UV-B will get throughto the planet.

Ozone depletion, and theassociated rise in UV-Bradiation, can cause seriousdamage. For example, even a1% reduction in global ozone isexpected to cause a significantfall in crop yields. Also, a 1995study (Longstreth et al.)estimates that a sustained 10%decrease in global stratosphericozone would lead to 250,000new cases of nonmelanoma skincancer, each year, in the U.S.alone.

Ozone “hole”refers to amajordecrease instratosphericozone, not thecompleteabsence of it.

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So far in 1997, ozone depletion over southern Canada has also been more moderate than in 1995: FromJanuary to June 1997— typically when depletion is at its worst— the average ozone reduction for southernCanada was 5.9% (figure 2). For southwestern B.C. during the same period, the average ozoneconcentration was 3.1% below normal. (Appendix 5 explains how ozone depletion data are calculated inCanada.)

Although damage to the ozone layer has reached serious proportions, it is expected to reach its maximumaround the turn of the century and then very gradually decrease, as a result of international efforts to stopthe depletion. (For more details on the future of the ozone layer, see section 11: Can We Halt OzoneDepletion Before It Is Too Late?)

Figure 1:

Stratospheric Ozone Reduction over Monitoring Sites across Canada:Percent Departure (averaged) from Normal Levels, Jan. 1 - Dec. 31, 1995

(Environment Canada, 1996)

-8.9%-8.2%

-7.2% -7.2%

-6.0% -5.8%-6.7%

-4.1% -3.9%

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Figure 2:

Stratospheric Ozone Reduction over Monitoring Sites across Canada:Percent Departure (averaged) from Normal Levels, Jan. 1 - June 30, 1997

(Environment Canada, 1997)

-3.1%

-8.7%

-6.4%-5.7%

-3.2%

-12.7%

-7.3%

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4. What Causes Ozone Depletion?Current evidence indicates that stratospheric ozone is being destroyed by halocarbons: a group of syntheticcompounds containing chlorine and bromine. Used in a wide variety of consumer goods, these chemicalsinclude chlorofluorocarbons (CFCs), halons (brominated fluorocarbons), carbon tetrachloride, methylchloroform, hydrochlorofluorocarbons (HCFCs) and methyl bromide. Together, all these ozone-depletingsubstances are known as “ODS.”

Halocarbons are not reactive, which means they can survive long enough to gradually float up, intact, intothe stratosphere. Once there, they are broken up by the intense UV-C radiation— releasing chlorine (fromCFCs, methyl chloroform and carbon tetrachloride), or bromine (from halons and methyl bromide). Theresulting chlorine and bromine destroy ozone at an alarming rate, by stripping an atom from the ozonemolecule. A single atom of chlorine can break apart 100,000 ozone molecules before it diffuses out of thestratosphere, and bromine is even more destructive than chlorine. To make matters worse, many ODS havea long atmospheric lifetime: up to several centuries. That means the ODS we release today may still bedestroying ozone hundreds of years from now.

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CFC compounds are the most widely used ODS, accounting for over 80% of total stratospheric ozonedepletion. Halons play a large role in ozone depletion, too. Their application (fire-extinguishing equipment)is quite limited compared to CFCs. However, their ability to destroy ozone, known as “Ozone-DepletingPotential” (ODP), is much higher: halons can destroy up to 10 times as much ozone as CFCs can.(Appendix 1 outlines the major uses of ODS, and their Ozone-Depleting Potential.) On top of their abilityto destroy stratospheric ozone, many halocarbons— especially CFCs and HCFCs— are powerfulgreenhouse gases, contributing to global climate change.

Different chemicals are being used and developed to replace ozone depleters, but they often haveenvironmental consequences of their own. HCFCs, for example, have become major, “transitional”substitutes for CFCs. These chemicals are much less harmful to stratospheric ozone than CFCs are. ButHCFCs still cause some ozone destruction and are potent greenhouse gases. For these reasons, theinternational community has agreed that HCFCs will be used only as interim CFC-replacements. Under theMontreal Protocol (see page 7), HCFCs will be eliminated by 2030. By that time, better alternatives willprobably be available.

Last, but certainly not least, are HFCs: hydrofluorocarbons. This group of chemicals is being developed toreplace CFCs and HCFCs, for uses such as vehicle air conditioning (HFC-134a). HFCs do not depleteozone, but they are strong greenhouse gases. CFCs are even more powerful contributors to global climatechange, though, so HFCs are still the better option until even safer substitutes are discovered.

Other replacements for ODS include chemicals or products that do not share the same chemical propertiesas ODS, but perform a similar function. In many sectors, alternatives are available and being used.Research continues in areas that are still dependent on ODS.

British Columbia’s ODS EmissionsBritish Columbia’s ODS emissions make up less than 1% of the world’s total, but they still are capable ofcausing significant ozone depletion. In 1990, for instance, British Columbians released about 1,099 tonnesof ozone-depleting substances into the atmosphere (figure 3), most of which will be destroying stratosphericozone for many years to come.

Figure 3:

Reported ODS Emissions in British Columbia, 1990

The amount of halon emissions is quite low compared tothat of CFC emissions. However, halons’ powerfulOzone-Depleting Potential significantly boosts theircontribution to ozone depletion.

In fact, halons are potentially the most serious kind ofODS emitted in B.C., posing a greater threat to theozone layer than do CFCs from vehicle air conditioners.

Type of Amount,ODS in Tonnes

CFCs 539HCFCs 150CFC/HCFC blends 57Halons 73ODS solvents 280

TOTAL: 1099

(Peat et al., 1992)

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5. The Impacts of Ozone DepletionCountries closest to the poles, such as Canada, will likely be hardest hit by a decrease in stratosphericozone, and the resulting increase in UV-B radiation. The major impacts are outlined below.

Human BeingsMore skin cancers, sunburns and photo-aging of the skin: Too much sunshine will roast us as red as alobster, and prematurely age our skin. Even worse, UV-B is the main cause of skin cancer. The effect iscumulative: childhood exposure, especially several bad sunburns, plays an important role in triggering skincancer later in life.

The bare-skinned, sun-worshiping habits of Canadians havecaused skin cancer rates to skyrocket in recent years. Because ofour inappropriate sun-protection habits (and not factoring in theimpacts of ozone depletion), Canadian children born today have aone-in-seven chance of developing skin cancer in their lifetime.Ozone depletion will intensify this risk, and narrow the timebetween repeated UV-B exposure and the appearance of skincancer.

A 1990 report by a team of B.C. dermatologists (Gallagher et al.) found “alarming increases” in all skincancers over the past two decades in the province, mainly due to sun exposure. It concluded that “theincreased financial burden on the health care system brought about by changes in incidence in BritishColumbia argues strongly for implementation of prevention programs even in provinces...that are not nowperceived to be high skin cancer risk areas.”

More cataracts, blindness and other eye diseases: UV radiation can damage several parts of the eye,including the lens, cornea, retina and conjunctiva. Cataracts (a clouding of the lens) are the major cause ofblindness in the world. A sustained 10% thinning of the ozone layer is expected to result in almost twomillion new cases of cataracts per year, globally (Environment Canada, 1993).

Immunosuppression (weakening of the human immune system): Early findings suggest that too much UV-B can suppress the human immune system, which may play a role in the development of skin cancer.

Plants and AnimalsTerrestrial plants: Several of the world’s major crop species are particularly vulnerable to increased UV-B, resulting in reduced growth, photosynthesis and flowering. These species include wheat, rice, barley,oats, corn, soybeans, peas, tomatoes, cucumbers, cauliflower, broccoli and carrots. The effect of ozonedepletion on the Canadian agricultural sector could be considerable. Only a few commercially importanttrees have been tested for UV-B sensitivity, but early results suggest that plant growth, especially inseedlings, is harmed by more intense UV-B radiation.

Freshwater and marine plants: UV-B radiation damages the productivity of phytoplankton— the single-celled organisms that live in the surface layer of the water, and form the first vital step in marine andfreshwater food chains. A 1990 study found that up to 12% of the phytoplankton living in the ocean underthe Antarctic ozone hole had been harmed by increased UV-B radiation. Decreases in phytoplankton coulddisrupt the fresh and saltwater food chains, and lead to a species shift in Canadian waters. Loss ofbiodiversity in our oceans, rivers and lakes could reduce fish yields for commercial and sport fisheries.

The common forms of skincancer— basal cell carcinomaand squamous cellcarcinoma— are usuallycurable, but can be disfiguring.Malignant melanoma is thedeadliest skin cancer. It ismore rare, but rapidlyincreasing in incidence.

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Animals: In domestic animals, UV-B overexposure may cause eye and skin cancers. Species of marineanimals in their developmental stage (e.g. young fish, shrimp larvae and crab larvae) have been threatenedin recent years by the increased UV-B radiation under the Antarctic ozone hole.

MaterialsWood, plastic, rubber, fabrics and many construction materials are degraded by UV radiation. Theeconomic impact of replacing and/or protecting materials could be significant.

6. Protecting the Ozone Layer: A Global EffortThe nations that produce and consume most of the world’s ODS have moved quickly to limit ozonedepletion through two major international agreements: the Vienna Convention for the Protection of theOzone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer.

The Vienna Convention for the Protection of the Ozone Layer (signed 1986; took effect 1988)The Vienna Convention laid down the principles (but not specific strategies) by which the internationalcommunity could work together to protect the ozone layer, carry out research and exchange information.Canada was the first of 22 countries to sign the Vienna Convention.

The Montreal Protocol on Substances that Deplete the Ozone Layer(signed in 1987; took effect January 1989)The Montreal Protocol is the first international agreement aimed at co-operative environmental action. Itsinitial goal was to greatly decrease ODS emissions by reducing the production and importation of the mainozone-depleting substances. The original Montreal Protocol committed its 24 signatories (includingCanada) to cutting CFC production and importation by 50% of 1986 levels by 1998, and freezing halonproduction and use at 1986 levels.

Two major amendments to the protocol have accelerated and intensified the ODS-control measures, movingfrom reductions in production and importation to actual phaseouts by set dates. The amendments have alsoextended the control measures to include more ODS. These changes followed scientific findings ofworsening ozone depletion and a conviction on the part of the protocol signatories that stronger action wasneeded. The amendments are known as the London Amendment (signed in 1990, took effect in 1992), andthe Copenhagen Amendment (signed in 1992, took effect in 1994).

The most recent, major meeting of the signatories took place in Montreal, in September 1997. Thesignatories agreed on a quicker phaseout of methyl bromide, moving the date for a total ban (in developedcountries) from 2010 up to 2005. They also established a licensing system to help governments trackinternational trade in ODS and discourage illegal sales.

The exceptions to the protocol’s phaseout requirements are “essential uses” of ODS. Production ofessential-use ODS is allowed only if all possible steps have been taken to minimize the essential use andany resulting emissions, and if there are no existing stocks of the substance. Appendix 2 shows theprotocol’s phaseout dates for the production and importation of ozone-depleting substances, based on thelatest adjustments (Vienna ‘95), along with Canada’s accelerated timetable. The amended MontrealProtocol will eventually translate into a 97% cut (compared to 1986 levels) in developed countries’production and use of ODS.

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The Montreal Protocol gives developing countries a 10-year grace period to implement the ODS phaseout.Also, the developed nations have established the “Interim Multilateral Fund,” (about $240 million, at thispoint) to help developing nations reduce their dependence on ODS. Because of these provisions, over 60developing nations— including India and China— have become partners in the Montreal Protocol.

At this point, 161 nations have signed the protocol, accounting for most of the world’s supply of ODS. Theprotocol signatories have also resolved to recover and recycle ODS that are already “banked” in millions ofproducts throughout the world— about 2.25 million metric tonnes of ODS. Illegal imports of virgin,recycled and recovered ODS have become a serious problem, which the signatories are trying to stopthrough export bans and trade sanctions.

7. The Costs and Benefits for Canada of Implementing the Montreal Protocol

Most “experts in the field”— such as scientists and policy makers— agree that the benefits of taking actionto prevent further ozone depletion will far outweigh the costs. This is certainly the picture painted bystudies carried out for Environment Canada on the costs and benefits of controlling ODS in Canada (Smith,D.A. et al., 1988; 1989 and 1993).

In fact, it is likely that the studies underestimated the total benefits of carrying out the Montreal Protocolbecause they considered only the (major) health effects of ozone depletion: skin cancers and cataracts. Dueto insufficient data, D.A. Smith et al. did not include the wide range of environmental and species impacts.Here are some highlights from those studies:• Reducing CFC and halon use, under the original (unamended) Montreal Protocol, were estimated to

result in health benefits worth $3.2 billion and costs of $0.3 billion (1989 Canadian dollars)— for theperiod between 1989 and 2075.

That works out to a net health benefit of $2.9 billion, and reflects only the lowering of CFC and halonconsumption, not the elimination of these and other ODS, which are now mandated under the lateramendments to the protocol.

• One study looked at the health benefits for Canadians that would result from the Copenhagen

amendment alone— in other words, the extra benefits, on top of the benefits to be gained from theoriginal Montreal Protocol and the first (London) amendment. The study found that this oneamendment, which shortened the phaseout for the main ODS by about four years, would lead toenormous health benefits.

Specifically, over the period between 1995 and 2080, carrying out the Copenhagen amendment inCanada would result in about 160,000 fewer incidences of skin cancer and 2,400 fewer deaths fromthis disease. There would also be around 44,000 fewer cases of cataracts. The value of these healthbenefits was estimated at almost $1.8 billion, in 1992 Canadian dollars.

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8. Canada’s Actions to Stop ODS Emissions

Canada assumed a central role in developing the Vienna Convention and the Montreal Protocol. It was alsoone of the first nations to enact legislation to meet and, in many cases, exceed its Montreal Protocolcommitments (see appendix 2). As a result of our country’s strong commitment to protecting the ozonelayer, Canada’s consumption (production + imports - exports) of new CFCs has decreased by 96%, overthe last ten years (1986 - 1996). This has been accomplished through the co-operative efforts of all levelsof government, and industry, trade and technical groups — with little industry disruption or economic loss.

The main task facing us now is preventing emissions of ODS stored in products and systems throughoutCanada, recovering those ODS, and switching to environmentally friendly alternatives. The challenge is notto be taken lightly: the amount of banked ODS in Canada equals several years of new ODS production.Another important challenge is developing safe ways to destroy ODS that have been recovered fromsystems, and are now in storage.

To “spread the work around” in an effective manner, the federal government has assumed responsibility forimplementing the provisions of the Montreal Protocol, including regulatory controls on the manufactureand importation of ODS. It is also taking the lead in researching ODS-destruction technologies, andeducating technicians working with ODS. The provinces and territories are responsible for implementinglaws and programs that prevent ODS leaks from products and systems, and require the safe recovery,storage and (in some cases) recycling of ODS.

It is important to emphasize that the federal and provincial governments do not work independently of eachother in carrying out their ODS-control responsibilities. They frequently share information and worktogether to carry out different initiatives. Beyond this, a federal-provincial group has been set up to makesure the efforts of each province to stop ODS emissions mesh well with those of the other provinces and thefederal government. The actions of this group are described below, under Federal-Provincial Activities.

Federal InitiativesLegislation: The federal legislation controls the manufacture and importation of new ODS. Four federalODS regulations were passed, under the Canadian Environmental Protection Act (CEPA), between 1989and 1993. However, these were replaced in 1994 by two sets of regulations, which strengthen and expandCanada’s earlier commitments:• Ozone-Depleting Substances (ODS) Regulations

These regulations control the importation, manufacture, use, sale and export of bulk ODS: CFCs,halons, carbon tetrachloride, methyl chloroform, HBFCs, methyl bromide and HCFCs.

• Ozone-Depleting Substances (ODS) Products RegulationsThese regulations control the importation, manufacture and sale of certain products that contain orwere made with CFCs or halons.

Although the provinces are responsible for passing regulations to stop ODS emissions, federal facilities arenot covered by such regulations. To close this regulatory gap, Environment Canada is developingregulations to prevent ODS emissions at federal facilities, slated to be in place by the end of 1997.

Scientific Monitoring and Research: The federal government operates 12 stratospheric ozone monitoringstations across the country (see appendix 5). The B.C. station is located on Saturna Island, nearVancouver. Canada also runs the World Ozone Data Centre, in Toronto, under the auspices of the UnitedNations World Meteorological Organization.

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Communication and Education: The federal government is taking action in a number of areas, under itsOzone Protection Program. Besides regular communication efforts and the development of educationalcurriculum, the government has launched the “Ozone Watch” and the “UV Index”:• The Ozone Watch summarizes ozone levels recorded at 10 of Canada’s 12 ozone-monitoring stations

over a two-week period, and compares them with long-term averages.• The UV Index is designed to help Canadians protect themselves from overexposure to UV radiation, by

providing daily forecasts of the amount of radiation expected for different areas of the country. The UVIndex is reported on a scale of 0 to 10: “9+” is an “extreme” radiation category, meaning that sunburnsand skin damage can occur in less than 15 minutes, and full precautions are necessary.

Federal-Provincial ActivitiesThe provincial governments* are key players in ODS recovery and recycling, as an essential complement tothe national regulations and programs. All but Newfoundland and the Northwest Territories have passedODS-control regulations, aimed at stopping ODS emissions from refrigeration, air-conditioning, fire-extinguishing and solvent-cleaning systems throughout Canada. (Newfoundland’s regulation should bepromulgated by the end of 1997 and the NWT have a guideline in place.) The newer provincial regulationsinclude more recently controlled substances (under the Montreal Protocol and federal laws), such as HFCs.*In this section, the term “provincial governments” includes the Yukon and Northwest Territories.

Major differences in the scope and strength of the provincial regulations could thwart Canada’s efforts toeliminate ODS emissions. To prevent such discrepancies, the Canadian Council of Ministers of theEnvironment (CCME) set up the “Federal-Provincial Working Group on Controls Harmonization forOzone-Depleting Substances” in 1989. Composed of representatives from the federal and provincialgovernments, the group’s main focus has been to develop a co-ordinated, national ODS-control strategy,and to harmonize the policies, regulations and programs adopted by the provinces.

In the early 1990s, the working group produced its first phase of the national strategy, covering CFCemissions. This “National Action Plan” was revised in June 1997, following national consultations withstakeholder groups. It now includes all ODS and their associated systems, as well as ODS-alternatives thatdo not cause ozone depletion but contribute to global climate change (e.g. HFCs). New goals, actions andschedules have been identified to strengthen and speed up the national process of controlling ODS. (Seeappendix 4 for the priority tasks of the ‘97 National Action Plan.)

In a further effort to support the provincial initiatives, Environment Canada has produced two (voluntary)environmental codes of practice, under CEPA. The codes are invaluable “how-to” guides to preventingODS leaks, in order to fulfil the requirements of the provincial ODS-control regulations.

Also, Environment Canada, the provinces, and the Heating, Refrigeration and Air Conditioning Institute(HRAI) have developed an ODS-control certification course for service technicians— on the properhandling, recovery and recycling of ODS. So far, over 75,000 (of about 100,000) technicians across thecountry have received certification under the “Environmental Awareness Training Course for ODSControl.”

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9. British Columbia’s Initiatives

Legislation: The Ozone-Depleting Substances (ODS) RegulationHere in B.C., the provincial government has passed a regulation that puts a lid on the ozone-depletingchemicals stored in products and equipment, and encourages consumers and industry to useenvironmentally safe alternatives. The Ozone-Depleting Substances Regulation (1993) controls all CFCs,halons and HCFCs, as well as methyl chloroform and carbon tetrachloride. Methyl bromide and HFCs arenot regulated yet. (See appendix 3 for more details on the regulation.)

One of the most advanced of the provincial regulations, the B.C. law prohibits venting of ODS, andrequires that equipment leaks be repaired as soon as they are detected. ODS must be recovered asefficiently as possible— during repair work or before an ODS-based product is discarded— and eitherrecycled or held for destruction. To make sure that ODS are recovered correctly, technicians working withthese chemicals must have completed Environment Canada’s ODS-control certification course.

In addition, ODS substitutes must be used as soon as possible. Motor vehicle air conditioners (MVACs),for example, are a large source of CFC emissions. To address this problem and encourage the switch toenvironmentally friendly alternatives, the regulation states that MVACs in vehicles of model year 1995 ornewer must not use ODS. Also, as of October 1, 1997, it will be illegal to recharge all MVACs— new orold— with CFCs.

The ODS Regulation has been enhanced to require that a person servicing an MVAC system on or afterOctober 1, 1997 must have successfully completed an MVAC course approved by BC Environment, whichteaches technicians how to service and retrofit MVACs properly. In the spring of 1997, the InsuranceCorporation of British Columbia (ICBC) and the Automotive Retailers Association began offering aministry-approved course for MVAC technicians throughout the province.

Activities Supporting the ODS RegulationIn November 1994, BC Environment conducted a random audit of almost 100 B.C. companies using ODSin some way. In general, the audit found a very high awareness of the ODS Regulation, and all thecompanies had the necessary recovery and recycling equipment. Over 60% of the audited companies haddocumentation showing their employees had taken, and been certified under, the ODS-control course. (Inall of B.C., more than 11,000 technicians have taken this course.) However, there was significantnoncompliance with the regulation’s labeling and record-keeping requirements.

In 1996, the Automotive Retailers Association conducted a random audit of 350 businesses in B.C.’svehicle repair industry, to determine compliance with the labeling, record-keeping, repairing and trainingrequirements of the ODS Regulation. BC Environment will prepare a summary of this audit in 1998.

With respect to controlling halons, BC Environment has completed annual summaries of industrial halon-management plans, and will investigate the development of a collection program for portable, halon-basedfire extinguishers.

BC Environment also participates in the Federal-Provincial Working Group on Controls Harmonization(ODS).

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Getting the Word OutThe provinces play a huge role in raising Canadians’ understanding about ozone depletion, how they canhelp preserve the ozone layer, and how they can protect themselves from UV-B radiation. In B.C., thegovernment has placed a strong emphasis on communication and education— not only about stratosphericozone depletion, but the other major air quality issues, too.

BC Environment has produced a brochure on ozone depletion, as well as fact sheets and a poster explainingthe ODS Regulation. It has also written a compliance guide to the ODS Regulation and a summary of the‘94 audit (ODS & You), both of which have been widely distributed throughout the industry. Under theB.C. regulation, people who sell ODS or products containing such chemicals, must display informationabout ODS and their destructive effect on the ozone layer.

10. The Challenges AheadWe have accomplished a great deal in addressing stratospheric ozone depletion since the Montreal Protocolwas signed in 1987. For example, global CFC production has been reduced by more than 77%. Thephaseout of CFCs and other ODS is expected to lead to a scenario in which ozone depletion reaches itsmaximum around 2000, and then very gradually declines. Also, concerted educational campaigns in B.C.,Canada and worldwide have done much to educate people about the dangers of ozone depletion and UVradiation, and each individual’s role in preventing further ozone loss.

But there is more work to do. A tremendous amount of ODS is still making its way up to the stratosphere,where it will add to ozone destruction. Much more ODS (2.25 million tonnes) are sitting in products andequipment all over the world, and may eventually leak out unless they are safely recovered and destroyed.Increased ODS production and emissions in developing countries will intensify the problem.

BC Environment has identified the following initiatives that should be carried out in the near future by theprovincial and federal governments:

The Federal Government and the Other ProvincesIt is recommended that the federal government:• continue research, with industry, into technology for destroying or converting recovered ozone-

depleting substances. (The federal government intends to develop a CFC/halon destruction strategy bythe end of 1998.) Such technology is urgently needed to get rid of ODS once and for all— in otherwords, to make sure recovered and recycled ODS do not find their way into the atmosphere, throughoperational problems, leaks and illegal practices. Although in its infancy, ODS-destruction technologyis under development around the world;

• encourage the other provinces to adopt a phaseout date for CFCs in MVACs, as B.C. and NewBrunswick have done. Similar regulatory requirements in other provinces would discourage cross-border access to repairs, and accelerate the conversion to non-ODS refrigerants. The National ActionPlan calls for a January 1, 2000 ban on refilling MVACs with CFCs;

• step up border inspections to catch illegal smuggling of ODS. The U.S. Environmental ProtectionAgency is cracking down on illegal imports, which have become a serious problem;

• fund research and education about UV-protective clothing; and

• increase public education about the dangers of ozone depletion and intensified UV radiation.

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The B.C. Ministry of Environment, Lands and ParksThe Ministry of Environment, Lands and Parks will investigate options to:• expand the scope and strength of the ODS Regulation in co-operation with other provinces. The

potential changes include: - adding HFCs to the regulation as controlled substances. - prohibiting the use of recyclable containers (which can lead to ODS leaks). - adding references to new or updated federal codes of practice for CFCs, HFCs and halons;• support the federal government in phasing out methyl bromide;

• develop a plan under which B.C. ministries will remove Class 1 ODS from provincial government andCrown corporation equipment by 2015;

• continue communications and educational efforts to raise British Columbians’ awareness of ozonedepletion and UV radiation, and the ODS Regulation. Actions could include a campaign with theMinistry of Health, the Canadian Dermatology Association and other agencies;

• evaluate options to address the concerns identified by the 1994 and 1996 compliance audits.Specifically, the labeling and record-keeping requirements need improvement. More emphasis shouldbe placed on ensuring that only trained people are handling ODS. BC Environment also needs todetermine how much ODS the industry is recovering; and

• conduct periodic audits of various industry sectors to check on the degree of regulatory compliance.

11. Can We Halt Ozone Depletion Before It Is Too Late?Ozone is naturally produced in the atmosphere, so the ozone layer will be able to rebuild itself, oncehuman-caused ODS emissions have been eliminated. The international phaseout of ODS will graduallyreduce the stratospheric levels of chlorine and bromine to below “critical levels” (2,000 parts per trillion, or“ppt”)— that is, to the point when the ozone layer can begin to return to normal (see figure 4).

Stratospheric concentrations of chlorine and bromine are expected to reach their maximum within a fewyears and then slowly decline, thanks to the amended Montreal Protocol. The amount of stratospheric ozoneloss should follow the same pattern, peaking around the turn of the century.

By about 2050, stratospheric chlorine and bromine— and the degree of ozone loss— should have fallenbelow critical levels, and the ozone layer should be on the road to recovery. However, because CFCs,halons and other ODS can survive for a long time in the stratosphere, the ozone layer will probably notreturn to its natural state until the 22nd century.

The timing of ODS elimination and ozone layer recovery will also depend on how effectively and quicklycountries meet the targets of the amended Montreal Protocol. This includes the difficult tasks of stoppingillegal exports, ending ODS leaks from banked products and destroying recovered ODS.

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Figure 4:

Projected Recovery of the Ozone Layer

This figure shows past and projected amounts ofchlorine and bromine in the stratosphere, resultingfrom ODS emissions:

• without the controls of the Montreal Protocol;• under the protocol’s original provisions; and• under the Copenhagen Amendment.

Critical chlorine/bromine levels are at 2,000 ppt.

(WMO, Scientific Assessment, 1994)

Even though we won't be around in the 22nd century to see how the ozone layer has fared, we have astrong link with the people of that time and a deep responsibility to them. Will the children of tomorrowthank us for taking the necessary steps to preserve the ozone layer, or curse our apathy and inaction?The future health of the ozone layer depends on how governments, industries and individuals care for ittoday.

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Appendices

1. Major Ozone-Depleting Substances:Uses and Ozone-Depleting Potential (ODP)

Halocarbons have different abilities to break up ozone, depending on their chemical composition andatmospheric lifetime (which ranges from 20 years to several centuries). To allow for comparison, thesehalocarbons have been assigned a number expressing their “Ozone-Depleting Potential (ODP),” usingCFC-11 as a baseline (it has been given the number 1.0). The main uses of each ODS, and their Ozone-Depleting Potential, are described in the chart below.

Chemical Uses ODP

CFCs • coolants in refrigerators, freezers and air conditioners.Motor vehicle air conditioners (MVACs) are the largestsingle source of CFC emissions in B.C.

• industrial solvents, dry-cleaning agents and hospitalsterilants.

• foam products— such as soft-foam padding (e.g. cushions)and rigid foam (e.g. home insulation).

• part of the product, but not the propellant, in someaerosols. (CFCs are no longer used in Canada to propel hairspray, antiperspirants and deodorants from aerosol spraycans, due to a national ban in 1980. Similar bans are inplace in the U.S. and some European countries.)

CFC-11: 1.0CFC-12: 1.0CFC-13: 1.0CFC-112: 1.0CFC-113: 0.8CFC-114: 1.0CFC-115: 0.6

Halons • used in some fire extinguishers, in cases where materialsand equipment would be destroyed by water or some of theother fire-extinguisher chemicals.

Halon-1211 3.0Halon-1301: 10.0Halon-2402: 6.0

MethylChloroform

• used mainly in industry as an all-purpose solvent, mainlyfor cleaning metal and electronic parts. 0.1

CarbonTetrachloride

• used as an industrial solvent, agricultural fumigant, and inmany other industrial processes, including petrochemicalrefining and some fire extinguishers.

1.1

MethylBromide

• used as a pesticide, to fumigate soil, structures, andagricultural products. 0.6

HCFCs:the CFC“transitional”chemicals

• an interim step between strong ozone depleters andozone-friendly chemicals of the future. HCFC-22, the majorHCFC, is mostly used in refrigerators, air conditioners, heatpumps, aerosol sprays and some foam products.

HCFC-22: 0.055

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2. ODS Phaseout Dates under the Montreal Protocol (with amendments), andCanadian Timetable

This chart shows the Montreal Protocol’s revised phaseout dates for the production and importation ofozone-depleting substances, based on the latest amendments (Vienna ‘95)— along with Canada’saccelerated timetable.

ODS Montreal Protocol:Control Measures andPhaseout Dates(Developed Nations)

Canada’s Timetable:Control Measures andPhaseout Dates

CFCs; Methyl Chloroform(also HBFCs— not used inCanada)

Complete phaseout of production andimportation by Jan. 1, 1996.

Same.

Carbon Tetrachloride Complete phaseout of production andimportation by Jan. 1, 1996.

Same, except phaseoutdate is Jan. 1, 1995.

Halons Complete phaseout of production andimportation by Jan. 1, 1994.

Same (phaseout ofimportation: halons are notmade in Canada).

HCFCs HCFCs now classified as transitionalsubstances, and must be graduallyphased out according to a setreduction schedule. Final phaseout byJan. 1, 2030.

Use of HCFCs now limitedto substituting for CFCs orhalons. Nonrecoverableuses of HCFCs to stop by2010. Ban on production fordomestic use andimportation, by Jan. 1,2020.

Methyl Bromide Methyl bromide now a controlledsubstance.

Latest amendment (Sept. ‘97) callsfor:25% reduction by Jan. 1, 1999;50% reduction by Jan. 1, 2001;70% reduction by Jan. 1, 2003; andtotal ban by Jan. 1, 2005.

Faster phaseout schedule:25% reduction by 1998,andtotal ban by 2001.

Consumption: ODS production plus imports, minus exports.

Production: Amount of ODS produced, minus amount destroyed by approvedtechnologies,

minus amount entirely used as a feed stock in manufacturing other chemicals.(Not the amount recycled and reused.)

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3. Ozone-Depleting Substances Regulation (February 1993)

B.C.’s Ozone-Depleting Substances (ODS) Regulation— part of the Waste Management Act— puts a lidon chemicals that destroy the ozone layer, and encourages industry and individuals to adopt safealternatives.

This regulation applies to all British Columbians, since most of us use products that contain ODS. It isour responsibility to ensure our appliances and vehicle air conditioners do not release these harmfulsubstances. We should also insist that the ODS be collected for recycling— during repair work or beforean ODS-based product is discarded. The ozone destroyers should never be released into theatmosphere. Anyone who violates the ODS Regulation may be ticketed, or fined up to $200,000.

Here are the key requirements of B.C.’s ODS Regulation:

• Controlled substances (“ODS”) include all CFCs, halons, methyl chloroform, carbon tetrachloride andHCFCs.

• It is prohibited to vent ODS from air conditioning or refrigeration equipment, vehicle air conditioners,fire-extinguishing equipment (except to fight a fire), ODS containers, or recovery and recyclingequipment. This includes leak testing with ODS;

• Sources of leaks must be repaired as soon as they are detected;• ODS must be recovered as efficiently as possible, and recycled or held for destruction. ODS-laden

equipment (e.g. refrigerators, air conditioners and fire extinguishers) must be safely drained beforebeing discarded or scrapped;

• Technicians who service equipment containing ODS must use approved equipment to safely captureand/or recycle the chemicals (in accordance with Environment Canada’s code of practice), and mustrepair all leaks before recharging a system with more ODS;

• Such technicians must complete the ODS-control course before they can service a system, orpurchase and use ODS. (In British Columbia, the “Environmental Awareness Training Course forODS Control” is available through community colleges.);

• ODS retailers must accept ODS returned by service technicians or consumers, and recycle thesubstances or send them to the manufacturer;

• Beginning with model year 1995, vehicles that are manufactured, imported or sold in B.C. must notcontain ODS in their air conditioner. As of October 1, 1997, it will be illegal to recharge vehicle airconditioners with ODS refrigerants— so far, only B.C. and New Brunswick have set a final date forthis;

• People servicing an MVAC system on or after October 1, 1997 must have successfully completed anMVAC course approved by BC Environment, which teaches proper MVAC servicing and retrofittingtechniques.

• The manufacture, importation, sale or supply of a portable fire extinguisher containing an ODS isprohibited;

• Fire-extinguishing systems using halons must be phased out, but no deadline has been set, at thispoint. Owners of systems with over 40 kg of halons must supply BC Environment with a yearly planfor managing and, over time, eliminating halon use;

• CFCs, halons, methyl chloroform and carbon tetrachloride cannot be used in cleaners or sterilizationprocesses. Foams containing CFCs (as the blowing agent) can no longer be manufactured, importedor sold in B.C., and HCFC-blown packaging foams will be phased out, starting in 1998;

• Detailed records must be kept of all purchases, sales and servicing involving ODS. Also, ODS-ladenproducts must have a permanent label indicating the amount and kind of ODS; and

• ODS containers must either be refilled or returned to the manufacturer for recycling. Nonreturnableand nonrefillable ODS containers must not be manufactured, brought into B.C. or sold.

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4. The National Action Plan (June 1997): Priority Tasks

This chart outlines the top-priority tasks in the revised National Action Plan, produced by the Federal-Provincial Working Group on Controls Harmonization for Ozone-Depleting Substances.

Task Schedule Responsibility

Prohibit release, mandaterecovery and limitdispersive uses of all CFCs,HCFCs and HFCs.

End of 1999 Environment Canada

Provinces/Territories.

Mandate leak testing andrepair before top up ofsystems.

End of 1999 Environment Canada

Provinces/Territories

Produce discussion paperon the disposal of surplusCFCs and halons.

Develop strategic plan fordisposing of surplus CFCsand halons.

End of 1997

End of 1998

Environment Canada

Environment Canada

Implement additionalcontrols on HCFCs.

End of 1998 Environment Canada

Update EnvironmentalAwareness TrainingProgram to reflect therevised code of practice.

End of 1997 Environment Canada

Mandate use of refillableODS containers.

End of 1998 Environment Canada

Provinces/Territories

Prohibit recharging mobileair-conditioning systemswith CFCs.

Jan. 1, 2000 Environment Canada

Provinces Territories

Develop transition strategyfor metered-dose inhalers(MDIs) used to deliverasthma medicine.

End of 1997 Environment Canada

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5. A Note about Ozone Layer Monitoring in Canada

The degree of stratospheric ozone depletion over Canada is determined by data collected throughEnvironment Canada’s ozone monitoring network, consisting of 12 sites across Canada. Ozonemonitoring stations are located at Saturna Island (near Vancouver), Edmonton, Saskatoon, Winnipeg,Churchill, Resolute (NWT), Toronto, Montreal, Halifax, Goose Bay, Alert Bay and Eureka. (Data fromAlert Bay and Eureka are not included in Environment Canada’s weekly “Ozone Watch” reports andpublished statistics.)

The ozone measurements are made by the Brewer ozone spectrophotometer, a state-of-the-art spectralinstrument developed by Environment Canada, which is used worldwide to monitor ozone. The Brewerrecords the spectrum of ultraviolet radiation and measures the amount of ozone by comparing therelative intensities of two wavelengths of UV— one wavelength is absorbed by ozone and the other is not.

Scientists analyze the data from these monitoring stations to determine if, and by how much, theconcentration of ozone has diverged from “normal,” pre-1980 levels. “Normal” refers to the usual ozonethickness over a certain region, for that time of year (season), based on the averages of data collectedbetween 1960 and 1980. This definition of “normal” takes into account the seasonal changes in ozonethickness, and solar-cycle variations— i.e., such variations are seen as normal.

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