Ozone Layer Protection and You

What is meant by "ozone hole" ?

Since about 1975, scientists have detected a severe drop in ozone concentration in the layer over the Antarctica each spring. The situation then reached an alarming scale in 1987 when an international expedition found that half of the Antarctica's ozone have disappeared over a region twice the size of the United States, creating an enormous "hole" in the ozone layer. Concentrations of ozone fell by as much as 50% of the norm at altitude of 18 km. At mid-latitudes in the Northern Hemisphere, up to 3% decrease in ozone concentration was also observed.

(Severe Drop in Ozone Concentration)

Why it concerns you?

The ozone molecules form a protective layer which extends from about 16 km to 50 km up above the earth at low latitudes, and from about 8 km to 50 km at high latitudes. The ozone molecules absorb the sun's ultra violet radiation (UV) which will be harmful to us if it reaches the earth surface. With more UV radiation reaching the earth surface due to ozone depletion, human health and the environment will be adversely affected. The most significant effects will be the increased incidence of skin cancer, eye cataracts, damage to the human immune system and to the ecology of the earth.

What causes this phenomenon?

Scientists have reached consensus that ozone depletion in the stratosphere is caused by ozone depleting chemicals. These chemicals contain chlorine or bromine atom with inherent chemical stability and have long lifetime in the atmosphere, in the range of 40 to 150 years. These chemicals and other trace gases drift up into the stratosphere and become involved in chlorine-releasing reactions. The chlorine atoms then react with the ozone molecules in the presence of sunlight and destroy the ozone molecules. Just one chlorofluorocarbon molecule can destroy tens of thousands of ozone molecules.

These ozone-depleting chemicals are extensively used man-made chemicals including the followings: -

chlorofluorocarbons (CFCs);
halons;
1,1,1-trichloroethane (methyl chloroform);
carbon tetrachloride;
methyl bromide;
hydrobromofluorocarbons (HBFCs); and
hydrochlorofluorocarbons (HCFCs).

Image of ozone deplecting substances destroy the ozone molecules and allow more UV radiation reaching the earth

What are these ozone depleting substances (ODS) used for?

The following are the common usage of CFCs and HCFCs :

CFC-11, CFC-12 and HCFC-22 are used as cooling agents in home refrigerators, retail store refrigeration systems, chillers and air-conditioners.
CFC-11 and CFC-12 are used as propellants for aerosol sprays such as hair mousses and household cleaning products.
CFC-11 and CFC-12 are also used as blowing agents in the manufacture of foams for home furnishing, insulation and packaging. Some plastics may be shaped using CFCs, e.g. egg cartons, cups and cartons used in fast food operations. Rigid or semi-rigid foams are also used as thermal or sound insulation in refrigeration equipment, buildings and automobiles.
CFC-113 is a solvent for cleaning electronic circuit boards and computer components.

Halons are used as fire extinguishing agents. Bromochlorodifluoromethane (BCF) is commonly used in portable fire extinguishers. Bromotrifluoromethane (BTM) is used in fixed fire-fighting installations. 1,1,1-trichloroethane is commonly used as a:

solvent for cleaning electronic circuit boards and metal work such as watches and clockworks.
thinner such as that for correction fluid.
cleaning agent in the textile industry (dry cleaning).

Carbon tetrachloride is used as a cleaning agent in textile and electronics industries.

Can we get rid of the ODS?

There has been considerable progress in finding non-ozone-depleting substitutes for ODS in the last few years. Substitutes for air-conditioning and refrigeration applications are now available, such as that CFC-12 can be replaced by HFC-134a. There are also emerging markets for "drop-in" replacement for CFC and halons.

Alternative products or processes can be used in some cases including the following:

alternative insulating materials;
substitute food containers such as hydrocarbon blown polystyrene, plastic film wrap and bags;
alternative packaging materials such as plastic film bubble wraps; and
air-conditioning and refrigeration plants operating on non-CFC refrigerants.

CFC solvents can be substituted in some applications. For instance, petroleum solvents can be selected as a replacement for CFC-113 or 1,1,1-trichloroethane in cleaning applications. Aqueous cleaning, or even no-clean technology, are also alternative processes that can be used by the electronics industry. Many household and personal aerosol products, e.g. paint sprays and insecticides, now use hydrocarbons (e.g. propane and butane) as propellants instead of CFCs. Dimethyl ether may also be used as propellants replacing CFCs.

What are the international efforts in saving the ozone layer?

In September 1987, an international treaty aimed at saving the Earth's ozone layer, known as the Montreal Protocol on Substances that Deplete the Ozone Layer, was signed in Montreal, Canada. The Protocol requires the phasing out of the ODS in accordance with agreed schedules. Following lists the ODS phasing out schedules applicable to Hong Kong:

Halons

Import for local consumption banned by 1.1.1994

CFCs

Carbon Tetrachloride

1,1,1-Trichloroethane

Import for local consumption banned by 1.1.1996

HCFCs

Freeze consumption at base level starting 1.1.1996

Import for local consumption banned by 1.1.2030

How does Hong Kong control the ODS?

To fulfil Hong Kong Special Administrative Region's international obligations under the 1985 Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer, the Ozone Layer Protection Ordinance was enacted in July 1989 to provide a statutory framework for the control of ozone depleting substances. The chemicals under control are referred to as "scheduled substances" in the Ordinance (Please see Appendix 1). The Ordinance prohibits the manufacturing of such substances and imposes controls on the import and export of these substances through registration and licensing provisions. The following is a summary of the related control:

Measures	Commencement Date
Control of import and export of scheduled substances	1.7.1989
Banning of import for local consumption of halons	1.1.1994
Licensing of import of methyl bromide strictly for local quarantine and pre-shipment applications	1.1.1995
Banning of import for local consumption of CFCs, 1,1,1-trichloroethane,carbon tetrachloride and HBFCs	1.1.1996
Licensing of import of HCFCs for local consumption	1.1.1996

Under the registration and licensing system, persons who wish to import or export any of the ODS must:

first register with the Trade and Industry Department,
apply for a licence from the Trade and Industry Department on each occasion, and/or
possess the quota to import the HCFC for local consumption .

In 1993, two pieces of legislation were introduced under the Ozone Layer Protection Ordinance:

The Ozone Layer Protection (Products Containing Scheduled Substances) (Import Banning) Regulation
The Ozone Layer Protection (Controlled Refrigerants) Regulation

Copies of the Ozone Layer Protection Ordinance and subsidiary regulations are on sale at the Government Publications Centre. Also, they can be browsed from the web site of Bilingual Laws Information System at http://www.legislation.gov.hk.

What is the Ozone Layer Protection (Products Containing Scheduled Substances) (Import Banning) Regulation about?

This Regulation prohibits the import of products containing CFCs and halons from countries which are not Parties to the Montreal Protocol:

an air-conditioner or heat pump designed to cool the driver's or passengers' compartment of a motor vehicle (whether or not installed in the motor vehicle);
refrigeration equipment or air-conditioning or heat pump equipment (whether for domestic or commercial use);
an aerosol product other than an aerosol product containing a pharmaceutical product or medicine as defined in section 2 of the Pharmacy and Poisons Ordinance (Cap. 138);
insulation panel, insulation board or insulation pipe cover;
a pre-polymer;
portable fire extinguishers containing halon FROM ANY COUNTRIES.

What is the Ozone Layer Protection (Controlled Refrigerants) Regulation about?

This Regulation prohibits any intended release of controlled refrigerants from motor vehicle air-conditioners or refrigeration equipment containing more than 50 kg of refrigerant charge into the atmosphere, and to conserve the controlled refrigerants through the use of approved recycling and recovery equipment.

For enforcement and monitoring purposes, owners or operators of industrial/commercial refrigeration systems, as well as proprietors of garages, shall be required to keep records on relevant repair services and the amount of CFC-based refrigerants consumed. Proprietors of vehicle scrap-yards shall also be required to keep records on the number of motor vehicle air conditioners decommissioned as well as the amount of CFC-based refrigerants recovered from the decommissioned air conditioners.

How can I help to protect the ozone layer?

While the vast majority of ODS usage is either industrial or commercial, individuals can help in the following ways:

Buy air-conditioning equipment that does not use CFC as refrigerant.
Conduct regular inspection and maintenance of air-conditioning and refrigeration appliances to prevent and minimize refrigerant leakage.
For existing air-conditioning and refrigeration appliances that operate on CFCs, the refrigerant should be recovered or recycled whenever an overhaul of equipment is to be carried out. Replacing or retrofitting such equipment to operate on non-CFC refrigerant should also be considered.
When motor vehicle air-conditioners need servicing, make sure that the CFC refrigerants are properly recovered and recycled instead of being vented to the atmosphere.
When using CFC-113 as solvent or cleaning agent, make sure that the chemical is properly handled so that evaporation losses are minimized and the waste solution is recycled as far as possible. Alternative technologies such as aqueous cleaning should also be considered.

FURTHER INFORMATION

Enquiries concerning the Ozone Layer Protection Ordinance and any other general information on the registration and licensing provisions may be made to the Air Policy Group of Environmental Protection Department at the following address:

Address	Telephone	Facsimile
33/F, Revenue Tower,	2594 6261	2827 8040
5 Gloucester Road,	2594 6218
Wan Chai, Hong Kong	2594 6275

Enquiries regarding the application for registration and import or export licences may be made to the Non-textiles Licensing Unit of Trade and Industry Department at the following address:

Address	Telephone	Facsimile
Room 101A, 1/F., Trade and Industry Department Tower, 700 Nathan Road, Kowloon.	2398 5560	2380 8504

Address

Telephone

Facsimile

Room 101A, 1/F., Trade and Industry
Department Tower,
700 Nathan Road,
Kowloon.

2398 5560

2380 8504

December, 2005

Acknowledgement:

Permission to use the image of "ozone hole" from the Ozone Processing Team, Goddard Space Flight Centre, NASA, and the ozone depleting illustration schematic from the Centre for Atmospheric Science, Chemistry Dept., University of Cambridge ("Ozone Hole Tour" website address, http://www.atm.ch.cam.ac.uk/tour/) is gratefully acknowledged.

Appendix 1

SCHEDULE

Scheduled Substances

PART 1 Chlorofluorocarbons (CFC)

Chemical Name		Common Name
CFCl₃	Trichlorofluoromethane	CFC-11
CF₂Cl₂	Dichlorodifluoromethane	CFC-12
C₂F₃Cl₃	Trichlorotrifluoroethane	CFC-113
C₂F₄Cl₂	Dichlorotetrafluoroethane	CFC-114
C₂F₅Cl	Chloropentafluoroethane	CFC-115

PART 2 Halons

Chemical Name		Common Name
CF₂BrCl	Bromochlordifluoromethane	halon 1211
CF₃Br	Bromotrifluoromethane	halon 1301
C₂F₄Br₂	Dibromotetrafluoroethane	halon 2402

PART 3 Other Fully Halogenated Chlorofluorocarbons

Chemical Name		Common Name
CF₃Cl	Chlorotrifluoromethane	CFC-13
C₂FCl₅	Pentachlorofluoroethane	CFC-111
C₂F₂Cl₄	Tetrachlorodifluoroethane	CFC-112
C₃FCl₇	Heptachlorofluoropropane	CFC-211
C₃F₂Cl₆	Hexachlorodifluoropropane	CFC-212
C₃F₃Cl₅	Pentachlorotrifluoropropane	CFC-213
C₃F₄Cl₄	Tetrachlorotetrafluoropropane	CFC-214
C₃F₅Cl₃	Trichloropentafluoropropane	CFC-215
C₃F₆Cl₂	Dichlorohexafluoropropane	CFC-216
C₃F₇Cl	Chloroheptafluoropropane	CFC-217

PART 4 Methyl Chloroform

Chemical Name		Common Name
C₂H₃Cl₃	1,1,1-Trichloroethane	Methyl Chloroform

PART 5 Carbon Tetrachloride

Chemical Name		Common Name
CCl₄	Tetrachloromethane	Carbon Tetrachloride

PART 6 Methyl Bromide

Chemical Name		Common Name
CH₃Br	Bromomethane	Methyl Bromide

PART 7 Hydrobromofluorocarbons (HBFC)

Chemical Name		Common Name
CHFBr₂	Dibromofluoromethane	---
CHF₂Br	Bromodifluoromethane	HBFC-22B1
CH₂FBr	Bromofluoromethane	---
C₂HFBr₄	Tetrabromofluoroethane	---
C₂HF₂Br₃	Tribromodifluoroethane	---
C₂HF₃Br₂	Dibromotrifluoroethane	---
C₂HF₄Br	Bromotetrafluoroethane	---
C₂H₂FBr₃	Tribromofluoroethane	---
C₂H₂F₂Br₂	Dibromodifluoroethane	---
C₂H₂F₃Br	Bromotrifluoroethane	---
C₂H₃FBr₂	Dibromofluoroethane	---
C₂H₃F₂Br	Bromodifluoroethane	---
C₂H₄FBr	Bromofluoroethane	---
C₃HFBr₆	Hexabromofluoropropane	---
C₃HF₂Br₅	Pentabromodifluoropropane	---
C₃HF₃Br₄	Tetrabromotrifluoropropane	---
C₃HF₄Br₃	Tribromotetrafluoropropane	---
C₃HF₅Br₂	Dibromopentafluoropropane	---
C₃HF₆Br	Bromohexafluoropropane	---
C₃H₂FBr₅	Pentabromofluoropropane	---
C₃H₂F₂Br₄	Tetrabromodifluoropropane	---
C₃H₂F₃Br₃	Tribromotrifluoropropane	---
C₃H₂F₄Br₂	Dibromotetrafluoropropane	---
C₃H₂F₅Br	Bromopentafluoropropane	---
C₃H₃FBr₄	Tetrabromofluoropropane	---
C₃H₃F₂Br₃	Tribromodifluoropropane	---
C₃H₃F₃Br₂	Dibromotrifluoropropane	---
C₃H₃F₄Br	Bromotetrafluoropropane	---
C₃H₄FBr₃	Tribromofluoropropane	---
C₃H₄F₂Br₂	Dibromodifluoropropane	---
C₃H₄F₃Br	Bromotrifluoropropane	---
C₃H₅FBr₂	Dibromofluoropropane	---
C₃H₅F₂Br	Bromodifluoropropane	---
C₃H₆FBr	Bromofluoropropane	---

PART 8 Hydrochlorofluorocarbons (HCFC)

Chemical Name		Common Name
CHFCl₂	Dichlorofluoromethane	HCFC-21
CHF₂Cl	Chlorodifluoromethane	HCFC-22
CH₂FCl	Chlorofluoromethane	HCFC-31
C₂HFCl₄	Tetrachlorofluoroethane	HCFC-121
C₂HF₂Cl₃	Trichlorodifluoroethane	HCFC-122
C₂HF₃Cl₂	Dichlorotrifluoroethane	HCFC-123
C₂HF₄Cl	Chlorotetrafluoroethane	HCFC-124
C₂H₂FCl₃	Trichlorofluoroethane	HCFC-131
C₂H₂F₂Cl₂	Dichlorodifluoroethane	HCFC-132
C₂H₂F₃Cl	Chlorotrifluoroethane	HCFC-133
C₂H₃FCl₂	Dichlorofluoroethane	HCFC-141
C₂H₃F₂Cl	Chlorodifluoroethane	HCFC-142
C₂H₄FCl	Chlorofluoroethane	HCFC-151
C₃HFCl₆	Hexachlorofluoropropane	HCFC-221
C₃HF₂Cl₅	Pentachlorodifluoropropane	HCFC-222
C₃HF₃Cl₄	Tetrachlorotrifluoropropane	HCFC-223
C₃HF₄Cl₃	Trichlorotetrafluoropropane	HCFC-224
C₃HF₅Cl₂	Dichloropentafluoropropane	HCFC-225
C₃HF₆Cl	Chlorohexafluoropropane	HCFC-226
C₃H₂FCl₅	Pentachlorofluoropropane	HCFC-231
C₃H₂F₂Cl₄	Tetrachlorodifluoropropane	HCFC-232
C₃H₂F₃Cl₃	Trichlorotrifluoropropane	HCFC-233
C₃H₂F₄Cl₂	Dichlorotetrafluoropropane	HCFC-234
C₃H₂F₅Cl	Chloropentafluoropropane	HCFC-235
C₃H₃FCl₄	Tetrachlorofluoropropane	HCFC-241
C₃H₃F₂Cl₃	Trichlorodifluoropropane	HCFC-242
C₃H₃F₃Cl₂	Dichlorotrifluoropropane	HCFC-243
C₃H₃F₄Cl	Chlorotetrafluoropropane	HCFC-244
C₃H₄FCl₃	Trichlorofluoropropane	HCFC-251
C₃H₄F₂Cl₂	Dichlorodifluoropropane	HCFC-252
C₃H₄F₃Cl	Chlorotrifluoropropane	HCFC-253
C₃H₅FCl₂	Dichlorofluoropropane	HCFC-261
C₃H₅F₂Cl	Chlorodifluoropropane	HCFC-262
C₃H₆FCl	Chlorofluoropropane	HCFC-271