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Ozone Depletion Publications, References and Resources

Ozone Depleting Substances, Definitions, Publications, References and Resources

1. What is good ozone
2. What is Bad ozone (ground-level ozone )
3. The science of ozone depletion
4. The effects of ozone depletion
5. Ozone depletion graphics and images

The ODS are split into two groups under the Clean Air Act: Class I ODS, such as chlorofluorocarbons (CFCs), and Class II ODS, such as hydrochlorofluorocarbons (HCFCs).

For each ODS, this page provides the compound’s atmospheric lifetime, O zone Depletion Potential (ODP), Global Warming Potential (GWP), and Chemistry Abstract Service (CAS) registry numbers.

Information on acceptable ODS alternatives (e.g., hydrofluorocarbons) is available through EPA’s Significant New Alternatives Policy (SNAP) Program.

• Class I ODS
• Class II ODS

Class I ODS

Class I ODS are divided into eight groups.

• Class I ODS listed in Groups 1 through 5 are identified in Title VI of the Clean Air Act.
• Class I ODS listed in Groups 6 and 7,  methyl bromide and hydrobromofluorocarbons, are identified in EPA's Accelerated Phaseout final rule.
• Class I ODS listed in Group 8, chlorobromomethane, is identified in EPA's Chlorobromomethane Phaseout final rule.

Chemical Name	Lifetime, in years	ODP1 (Montreal Protocol)	ODP2 (WMO 2011)	GWP1 (AR4)	GWP2 (AR5)	CAS Number
Group I
CFC-11 (CCl3F) Trichlorofluoromethane	45	1	1	4750	4660	75-69-4
CFC-12 (CCl2F2) Dichlorodifluoromethane	100	1	0.82	10900	10200	75-71-8
CFC-113 (C2F3Cl3) 1,1,2-Trichlorotrifluoroethane	85	0.8	0.85	6130	5820	76-13-1
CFC-114 (C2F4Cl2) Dichlorotetrafluoroethane	190	1	0.58	10000	8590	76-14-2
CFC-115 (C2F5Cl) Monochloropentafluoroethane	1020	0.6	0.5	7370	7670	76-15-3
Group II
Halon 1211 (CF2ClBr) Bromochlorodifluoromethane	16	3	7.9	1890	1750	353-59-3
Halon 1301 (CF3Br) Bromotrifluoromethane	65	10	15.9	7140	6290	75-63-8
Halon 2402 (C2F4Br2) Dibromotetrafluoroethane	20	6	13.0	1640	1470	124-73-2
Group III
CFC-13 (CF3Cl) Chlorotrifluoromethane	640	1	1	14420	13900	75-72-9
CFC-111 (C2FCl5) Pentachlorofluoroethane		1	1			354-56-3
CFC-112 (C2F2Cl4) Tetrachlorodifluoroethane		1	1			76-12-0
CFC-211 (C3FCl7) Heptachlorofluoropropane		1	1			422-78-6
CFC-212 (C3F2Cl6) Hexachlorodifluoropropane		1	1			3182-26-1
CFC-213 (C3F3Cl5) Pentachlorotrifluoropropane		1	1			2354-06-5
CFC-214 (C3F4Cl4) Tetrachlorotetrafluoropropane		1	1			29255-31-0
CFC-215 (C3F5Cl3) Trichloropentafluoropropane		1	1			4259-43-2
CFC-216 (C3F6Cl2) Dichlorohexafluoropropane		1	1			661-97-2
CFC-217 (C3F7Cl) Chloroheptafluoropropane		1	1			422-86-6
Group IV
CCl4 Carbon tetrachloride	26	1.1	0.82	1400	1730	56-23-5
Group V
Methyl Chloroform (C2H3Cl3) 1,1,1-trichloroethane	5	0.1	0.16	146	160	71-55-6
Group VI
Methyl Bromide (CH3Br)	0.8	0.7	0.66	5	2	74-83-9
Group VII
CHFBr2		1	1
HBFC-12B1(CHF2Br)		0.74
CH2FBr		0.73	0.73
C2HFBr4		0.3-0.8	0.3-0.8
C2HF2Br3		0.5-1.8	0.5-1.8
C2HF3Br2		0.4–1.6	0.4–1.6
C2HF4Br		0.7–1.2	0.7–1.2
C2H2FBr3		0.1–1.1	0.1–1.1
C2H2F2Br2		0.2–1.5	0.2–1.5
C2H2F3Br		0.7–1.6	0.7–1.6
C2H3FBr2		0.1–1.7	0.1–1.7
C2H3F2Br		0.2–1.1	0.2–1.1
C2H4FBr		0.07–0.1	0.07–0.1
C3HFBr6		0.3–1.5	0.3–1.5
C3HF2Br5		0.2–1.9	0.2–1.9
C3HF3Br4		0.3–1.8	0.3–1.8
C3HF4Br3		0.5–2.2	0.5–2.2
C3HF5Br2		0.9–2.0	0.9–2.0
C3HF6Br		0.7–3.3	0.7–3.3
C3H2FBr5		0.1–1.9
C3H2F2Br4		0.2–2.1	0.2–2.1
C3H2F3Br3		0.2–5.6	0.2–5.6
C3H2F4Br2		0.3–7.5	0.3–7.5
C3H2F5Br		0.9–1.4	0.9–1.4
C3H3FBr4		0.08­–1.9	0.08­–1.9
C3H3F2Br3		0.1–3.1	0.1–3.1
C3H3F3Br2		0.1–2.5	0.1–2.5
C3H3F4Br		0.3–4.4	0.3–4.4
C3H4FBr3		0.03–0.3	0.03–0.3
C3H4F2Br2		0.1–1.0	0.1–1.0
C3H4F3Br		0.07–0.8	0.07–0.8
C3H5FBr2		0.04–0.4	0.04–0.4
C3H5F2Br		0.07–0.8	0.07–0.8
C3H6FBr		0.02–0.7	0.02–0.7
Group VIII
CH2BrCl Chlorobromomethane	0.37	0.12	0.12

Why are there multiple values given for the ODPs and GWPs?

The numbers in the “ODP1” column are from the Montreal Protocol. Some numbers have been updated as per amendments to the Protocol.

Data in the “ODP2” column come from WMO’s Scientific Assessment of Ozone Depletion: 2010.¹ ODP values listed are semi-empirical and can be found in Table 5-1 of the document.

The numbers in the “GWP1” column represent global warming potentials over a 100-year time horizon. The numbers are from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report: Climate Change 2007 (AR4).² The values listed are for direct radiative forcing and can be found in Table 2.14 of the “Physical Science Basis” contribution to the report.

The numbers in the “GWP2” column also represent global warming potentials over a 100-year time horizon. The numbers are from the IPCC Fifth Assessment Report: Climate Change 2014 (AR5). The values listed are for direct radiative forcing and can be found in Table 8.A.1 of the “Physical Science Basis” contribution to the report.³

References

1. WMO (World Meteorological Organization), 2011: Scientific Assessment of Ozone Depletion: 2010. Global Ozone Research and Monitoring Project—Report No. 52, Geneva, Switzerland, 516 pp.
2. IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp.
3. IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp.

Class II ODS

Chemical Name	Lifetime, in years	ODP1 (Montreal Protocol)	ODP2 (WMO 2011)	GWP1 (AR4)	GWP2 (AR5)	CAS Number
HCFC-21 (CHFCl2) Dichlorofluoromethane	1.7	0.04		151	148	75-43-4
HCFC-22 (CHF2Cl) Monochlorodifluoromethane	11.9	0.055	0.04	1810	1760	75-45-6
HCFC-31 (CH2FCl) Monochlorofluoromethane		0.02				593-70-4
HCFC-121 (C2HFCl4) Tetrachlorofluoroethane		0.01-0.04				354-14-3
HCFC-122 (C2HF2Cl3) Trichlorodifluoroethane		0.02-0.08			59	354-21-2
HCFC-123 (C2HF3Cl2) Dichlorotrifluoroethane	1.3	0.02	0.01	77	79	306-83-2
HCFC-124 (C2HF4Cl) Monochlorotetrafluoroethane	5.9	0.022				2837-89-0
HCFC-131 (C2H2FCl3) Trichlorofluoroethane		0.007–0.05				359-28-4
HCFC-132b (C2H2F2Cl2) Dichlorodifluoroethane		0.008–0.05				1649-08-7
HCFC-133a (C2H2F3Cl) Monochlorotrifluoroethane		0.02–0.06				75-88-7
HCFC-141b (C2H3FCl2) Dichlorofluoroethane	9.2	0.11	0.12	725	782	1717-00-6
HCFC-142b (C2H3F2Cl) Monochlorodifluoroethane	17.2	0.065	0.06	2310	1980	75-68-3
HCFC-221 (C3HFCl6) Hexachlorofluoropropane		0.015–0.07				422-26-4
HCFC-222 (C3HF2Cl5) Pentachlorodifluoropropane		0.01–0.09				422-49-1
HCFC-223 (C3HF3Cl4) Tetrachlorotrifluoropropane		0.01–0.08				422-52-6
HCFC-224 (C3HF4Cl3) Trichlorotetrafluoropropane		0.01–0.09				422-54-8
HCFC-225ca (C3HF5Cl2) Dichloropentafluoropropane	1.9	0.025	0.02	122	127	422-56-0
HCFC-225cb (C3HF5Cl2) Dichloropentafluoropropane	5.9	0.033	0.03	595	525	507-55-1
HCFC-226 (C3HF6Cl) Monochlorohexafluoropropane		0.02–0.1				431-87-8
HCFC-231 (C3H2FCl5) Pentachlorofluoropropane		0.05–0.09				421-94-3
HCFC-232 (C3H2F2Cl4) Tetrachlorodifluoropropane		0.008–0.1				460-89-9
HCFC-233 (C3H2F3Cl3) Trichlorotrifluoropropane		0.007–0.23				7125-84-0
HCFC-234 (C3H2F4Cl2) Dichlorotetrafluoropropane		0.01–0.28				425-94-5
HCFC-235 (C3H2F5Cl) Monochloropentafluoropropane		0.03–0.52				460-92-4
HCFC-241 (C3H3FCl4) Tetrachlorofluoropropane		0.004–0.09				666-27-3
HCFC-242 (C3H3F2Cl3) Trichlorodifluoropropane		0.005–0.13				460-63-9
HCFC-243 (C3H3F3Cl2) Dichlorotrifluoropropane		0.007–0.12				460-69-5
HCFC-244 (C3H3F4Cl) Monochlorotetrafluoropropane		0.009–0.14
HCFC-251 (C3H4FCl3) Monochlorotetrafluoropropane		0.001–0.01				421-41-0
HCFC-252 (C3H4F2Cl2) Dichlorodifluoropropane		0.005–0.04				819-00-1
HCFC-253 (C3H4F3Cl) Monochlorotrifluoropropane		0.003–0.03				460-35-5
HCFC-261 (C3H5FCl2) Dichlorofluoropropane		0.002–0.02				420-97-3
HCFC-262 (C3H5F2Cl) Monochlorodifluoropropane		0.002–0.02				421-02-03
HCFC-271 (C3H6FCl) Monochlorofluoropropane		0.001–0.03				430-55-7

Why are there multiple values given for the ODPs and GWPs?

The numbers in the “ODP1” column are from the Montreal Protocol. Some numbers have been updated as per amendments to the Protocol.

Data in the “ODP2” column come from WMO’s Scientific Assessment of Ozone Depletion: 2010.¹ ODP values listed are semi-empirical and can be found in Table 5-1 of the document.

The numbers in the “GWP1” column represent global warming potentials over a 100-year time horizon. The numbers are from the IPCC Fourth Assessment Report: Climate Change 2007 (AR4).² The values listed are for direct radiative forcing and can be found in Table 2.14 of the “Physical Science Basis” contribution to the report.

The numbers in the “GWP2” column also represent global warming potentials over a 100-year time horizon. The numbers are from the IPCC Fifth Assessment Report: Climate Change 2014 (AR5). The values listed are for direct radiative forcing and can be found in Table 8.A.1 of the “Physical Science Basis: contribution to the report.³

References

1. WMO (World Meteorological Organization), 2011: Scientific Assessment of Ozone Depletion: 2010. Global Ozone Research and Monitoring Project—Report No. 52, Geneva, Switzerland, 516 pp.
2. IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp.
3. IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp.

Ozone Publications

ANNUAL REPORTS

1. Air Quality and Emissions Trends Report
   This annual publication describes trends in emissions and air concentrations for ozone, particulate matter and other common pollutants during the past ten years and assesses the current status of our nation's air quality. Reports are available online for several years.

PUBLICATIONS

1. Air Trends Report for Ground-level Ozone This report analyzes ozone levels in 2003 and looks at our current challenges and long-term prospects for continuing to reduce ground-level ozone.
2. The Regional Transport of Ozone (1998) (PDF, 4 pp, 249 KB) EPA brochure describing a rule known as the "NOx SIP Call," designed to reduce regional emissions of ozone-contributing nitrogen oxides during the summertime ozone season. NOx also contributes to the formation of particle pollution.
3. Ozone and Your Health (PDF, 2 pp, 449 KB) This short, colorful pamphlet tells who is at risk from exposure to ozone, what health effects are caused by ozone, and simple measures that can be taken to reduce health risk.
4. Ozone: Good Up High, Bad Nearby (PDF, 2 pp, 1391 KB) Ozone acts as a protective layer high above the earth, but it can be harmful to breathe. This publication provides basic information about ground-level and high-altitude ozone.
5. Smog - Who Does it Hurt? (PDF, 10 pp, 819 KB) This 8-page booklet provides more detailed information than "Ozone and Your Health" about ozone health effects and how to avoid them.
6. Summertime Safety: Keeping Kids Safe from Sun and Smog (PDF, 2 pp, 314 KB) This document discusses summer health hazards that pertain particularly to children and includes information about EPA's Air Quality Index and UV Index tools.
7. Air Quality Criteria Document for Ozone (February 2006) This comprehensive assessment of scientific data about the health and environmental effects of ground-level ozone is an important part of EPA's review of its ozone standards.

General Resources

This section includes links to domestic and international organizations that perform stratospheric ozone research, ozone depletion related measurement and monitoring, and other sources of stratospheric ozone science information.

1. UNEP Ozone Secretariat - The Secretariat for the Vienna Convention for the Protection of the Ozone Layer and for the Montreal Protocol on Substances that Deplete the Ozone Layer.
2. NOAA Climate Monitoring and Diagnostics Laboratory - CMDL includes several programs to measure important atmospheric characteristics.
3. NOAA Stratospheric Ozone Monitoring and Research - Includes data, measurements, and frequently asked questions from NOAA.
4. NOAA Climate Prediction Center Products: Stratosphere - Current satellite ozone maps; UV index bulletin; TOVS data, images.
5. NASA Ozone Hole Watch - Satellite instruments monitor the ozone layer. Images, data and information updated daily.
6. Online Papers at CEISN - This site provides the full text of an enormous number of papers on ozone depletion, including the original paper on the ozone hole .
7. Stratospheric Ozone Science Frequently Asked Questions by Dr. Robert Parson from the University of Colorado - This set of questions and answers provides carefully cited information. It goes into considerable detail and provides numerous references to original research.
8. World Meteorological Organization (WMO) Global Atmosphere Watch - Includes information about WMO's atmospheric monitoring and research.
9. British Antarctic Survey Ozone Hole Research - Information about the Antarctic Ozone Hole from the organization that discovered it.
10. Halogen Occultation Experiment (HALOE) - Vertical profiles of various trace gases relevant to ozone depletion such as water vapor and HF.
11. World Ozone and Ultraviolet Radiation Data Centre - Operated by Environment Canada, this Centre is a part of the World Meteorological Organization. Current and time series graphs of ozone and UV radiation over Canada and North America are also available.
12. EPA's Ultraviolet Monitoring Program - EPA operates and maintains a network of Brewer spectrophotometers throughout the United States, measuring full-sky spectrally-resolved solar radiation in the UV-B and UV-A bands. Visitors can create graphs of daily UV and ozone levels and download the data.
13. NASA's TOMS (Total Ozone Mapping Spectrometer) Multimedia Files: Ozone Depletion Movies, Graphics, and Original Data - This site is full of useful data and information. Download original ozone level data and see movies and graphics of ozone depletion and the Antarctic ozone hole. The site also lets you find the ozone level over your house!

ANNUAL REPORTS

1. Air Quality and Emissions Trends Report
   This annual publication describes trends in emissions and air concentrations for ozone, particulate matter and other common pollutants during the past ten years and assesses the current status of our nation's air quality. Reports are available online for several years.

MORE PUBLICATIONS

1. Air Quality Guide for Ozone - 1999
   This guide provides you with information about ways to protect your health when ozone levels reach the unhealthy range, and ways you can help reduce ozone air pollution.
   PDF version (31K)(About PDF)
   In Spanish
   
   
2. Air Quality Index - A Guide to Air Quality and Your Health - 2000
   This booklet explains EPA's Air Quality Index (AQI) and tells you about the health effects of major air pollutants.
   
   
3. Evaluating Exposures to Toxic Air Pollutants: A Citizen's Guide - 1991
   Toxic air pollutants can increase the chance of health problems and cause ecological impacts. This brochure from EPA's Air Risk Center discusses the process used to determine how much of a toxic air pollutant people are exposed to and how many people are exposed.
   
   
4. Haze -- How Air Pollution Affects the View (432K PDF) - 1999
   This two-page pamphlet gives a general description of what regional haze is, where it comes from, and what is being done to reduce it. For additional information, see EPA's Visibility website.
   
   
5. NOx -- How Nitrogen Oxides Affect the Way We Live and Breathe - 1998
   EPA tracks emissions of six principal air pollutants - carbon monoxide, lead, nitrogen oxides, particulate matter, sulfur dioxide, and volatile organic compounds. All have decreased significantly since passage of the Clean Air Act in 1970 -except for nitrogen oxides (NOx). This brochure tells about this pollutant and the steps that EPA is taking to reduce its emissions.
   
   
6. Ozone - Good Up High Bad Nearby - 1997
   Ozone acts as a protective layer high above the earth, but it can be harmful to breathe. This publication provides basic information about ground-level and high-altitude ozone.
   PDF version (295K) (About PDF)
   
   
7. Ozone and Your Health - 1999
   This short, colorful pamphlet tells who is at risk from exposure to ozone, what health effects are caused by ozone, and simple measures that can be taken to reduce health risk.
   PDF version (448K) (About PDF)
   In Spanish
   
   
8. The Plain English Guide to the Clean Air Act - Updated 2007
   A brief introduction to the 1990 version of the Clean Air Act, to help you understand what is in the law and how it may affect you.
   
   
9. Regional Haze and Visibility Protection: Clearing the Air and Improving the View - 1999
   A 1999 publication including an overview of visibility impairment, its causes, and the regional haze program.
   
   
10. Risk Assessment for Toxic Air Pollutants: A Citizen's Guide - 1991
    Risk assessment is the process used to estimate the risk of illness from a specific human exposure to a toxic air pollutant. This brochure from EPA's Air Risk Center gives an overview of the 4-step assessment process.
    
    
11. Smog - Who Does it Hurt? - 1999
    This 8-page booklet provides more detailed information than "Ozone and Your Health" about ozone health effects and how to avoid them.
    PDF version (818K) (About PDF)
    In Spanish
    
    
12. Taking Toxics Out of the Air -- Progress in Setting "Maximum Achievable Control Technology" Standards Under the Clean Air Act - 2000
    EPA is mandated by the Clean Air Act to significantly reduce daily, so-called "routine" emissions of toxic air pollutants. This document discusses the problem of air toxics, and describes the individual standards EPA has issued to reduce air toxic emissions from industries such as chemical manufacturing and petroleum refineries.
    PDF version (808K) (About PDF)

REFERENCES

1. AP-42 (Compilation of Air Pollutant Emission Factors)
   The Compilation of Air Pollutant Emission Factors, AP-42, is the authoritative source of information for estimating emissions of air pollutants from industrial, commercial, and residential sources. This page contains links to PDF and WordPerfect versions of each of the AP-42 chapters, as well as a link to OAQPS contacts for AP-42.
2. The Green Book
   Extensive information about nonattainment areas and National Ambient Air Quality Standards for the six criteria pollutants.
3. Health Effects Notebook for Hazardous Air Pollutants - Here you can obtain fact sheets that give detailed information about the effects on human health of substances defined as hazardous by the 1990 amendments of the Clean Air Act. There's also an explanation of topics and terms used in the fact sheets.