(a) List of class I substances

Within 60 days after November 15, 1990, the Administrator shall publish an initial list of class I substances, which list shall contain the following substances:


Group I

chlorofluorocarbon-11 (CFC-11)

chlorofluorocarbon-12 (CFC-12)

chlorofluorocarbon-113 (CFC-113)

chlorofluorocarbon-114 (CFC-114)

chlorofluorocarbon-115 (CFC-115)


Group II

halon-1211

halon-1301

halon-2402


Group III

chlorofluorocarbon-13 (CFC-13)

chlorofluorocarbon-111 (CFC-111)

chlorofluorocarbon-112 (CFC-112)

chlorofluorocarbon-211 (CFC-211)

chlorofluorocarbon-212 (CFC-212)

chlorofluorocarbon-213 (CFC-213)

chlorofluorocarbon-214 (CFC-214)

chlorofluorocarbon-215 (CFC-215)

chlorofluorocarbon-216 (CFC-216)

chlorofluorocarbon-217 (CFC-217)


Group IV

carbon tetrachloride


Group V

methyl chloroform


The initial list under this subsection shall also include the isomers of the substances listed above, other than 1,1,2-trichloroethane (an isomer of methyl chloroform). Pursuant to subsection (c), the Administrator shall add to the list of class I substances any other substance that the Administrator finds causes or contributes significantly to harmful effects on the stratospheric ozone layer. The Administrator shall, pursuant to subsection (c), add to such list all substances that the Administrator determines have an ozone depletion potential of 0.2 or greater.

(b) List of class II substances

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Terms Used In 42 USC 7671a

  • Administrator: means the Administrator of the Environmental Protection Agency. See 42 USC 7602
  • class I substance: means each of the substances listed as provided in section 7671a(a) of this title. See 42 USC 7671
  • class II substance: means each of the substances listed as provided in section 7671a(b) of this title. See 42 USC 7671
  • ozone-depletion potential: means a factor established by the Administrator to reflect the ozone-depletion potential of a substance, on a mass per kilogram basis, as compared to chlorofluorocarbon-11 (CFC-11). See 42 USC 7671
  • person: includes an individual, corporation, partnership, association, State, municipality, political subdivision of a State, and any agency, department, or instrumentality of the United States and any officer, agent, or employee thereof. See 42 USC 7602
  • production: refer to the manufacture of a substance from any raw material or feedstock chemical, but such terms do not include&mdash. See 42 USC 7671

Simultaneously with publication of the initial list of class I substances, the Administrator shall publish an initial list of class II substances, which shall contain the following substances:


hydrochlorofluorocarbon-21 (HCFC-21)

hydrochlorofluorocarbon-22 (HCFC-22)

hydrochlorofluorocarbon-31 (HCFC-31)

hydrochlorofluorocarbon-121 (HCFC-121)

hydrochlorofluorocarbon-122 (HCFC-122)

hydrochlorofluorocarbon-123 (HCFC-123)

hydrochlorofluorocarbon-124 (HCFC-124)

hydrochlorofluorocarbon-131 (HCFC-131)

hydrochlorofluorocarbon-132 (HCFC-132)

hydrochlorofluorocarbon-133 (HCFC-133)

hydrochlorofluorocarbon-141 (HCFC-141)

hydrochlorofluorocarbon-142 (HCFC-142)

hydrochlorofluorocarbon-221 (HCFC-221)

hydrochlorofluorocarbon-222 (HCFC-222)

hydrochlorofluorocarbon-223 (HCFC-223)

hydrochlorofluorocarbon-224 (HCFC-224)

hydrochlorofluorocarbon-225 (HCFC-225)

hydrochlorofluorocarbon-226 (HCFC-226)

hydrochlorofluorocarbon-231 (HCFC-231)

hydrochlorofluorocarbon-232 (HCFC-232)

hydrochlorofluorocarbon-233 (HCFC-233)

hydrochlorofluorocarbon-234 (HCFC-234)

hydrochlorofluorocarbon-235 (HCFC-235)

hydrochlorofluorocarbon-241 (HCFC-241)

hydrochlorofluorocarbon-242 (HCFC-242)

hydrochlorofluorocarbon-243 (HCFC-243)

hydrochlorofluorocarbon-244 (HCFC-244)

hydrochlorofluorocarbon-251 (HCFC-251)

hydrochlorofluorocarbon-252 (HCFC-252)

hydrochlorofluorocarbon-253 (HCFC-253)

hydrochlorofluorocarbon-261 (HCFC-261)

hydrochlorofluorocarbon-262 (HCFC-262)

hydrochlorofluorocarbon-271 (HCFC-271)


The initial list under this subsection shall also include the isomers of the substances listed above. Pursuant to subsection (c), the Administrator shall add to the list of class II substances any other substance that the Administrator finds is known or may reasonably be anticipated to cause or contribute to harmful effects on the stratospheric ozone layer.

(c) Additions to the lists

(1) The Administrator may add, by rule, in accordance with the criteria set forth in subsection (a) or (b), as the case may be, any substance to the list of class I or class II substances under subsection (a) or (b). For purposes of exchanges under section 7661f 1 of this title, whenever a substance is added to the list of class I substances the Administrator shall, to the extent consistent with the Montreal Protocol, assign such substance to existing Group I, II, III, IV, or V or place such substance in a new Group.

(2) Periodically, but not less frequently than every 3 years after November 15, 1990, the Administrator shall list, by rule, as additional class I or class II substances those substances which the Administrator finds meet the criteria of subsection (a) or (b), as the case may be.

(3) At any time, any person may petition the Administrator to add a substance to the list of class I or class II substances. Pursuant to the criteria set forth in subsection (a) or (b) as the case may be, within 180 days after receiving such a petition, the Administrator shall either propose to add the substance to such list or publish an explanation of the petition denial. In any case where the Administrator proposes to add a substance to such list, the Administrator shall add, by rule, (or make a final determination not to add) such substance to such list within 1 year after receiving such petition. Any petition under this paragraph shall include a showing by the petitioner that there are data on the substance adequate to support the petition. If the Administrator determines that information on the substance is not sufficient to make a determination under this paragraph, the Administrator shall use any authority available to the Administrator, under any law administered by the Administrator, to acquire such information.

(4) Only a class II substance which is added to the list of class I substances may be removed from the list of class II substances. No substance referred to in subsection (a), including methyl chloroform, may be removed from the list of class I substances.

(d) New listed substances

In the case of any substance added to the list of class I or class II substances after publication of the initial list of such substances under this section, the Administrator may extend any schedule or compliance deadline contained in section 7671c or 7671d of this title to a later date than specified in such sections if such schedule or deadline is unattainable, considering when such substance is added to the list. No extension under this subsection may extend the date for termination of production of any class I substance to a date more than 7 years after January 1 of the year after the year in which the substance is added to the list of class I substances. No extension under this subsection may extend the date for termination of production of any class II substance to a date more than 10 years after January 1 of the year after the year in which the substance is added to the list of class II substances.

(e) Ozone-depletion and global warming potential

Simultaneously with publication of the lists under this section and simultaneously with any addition to either of such lists, the Administrator shall assign to each listed substance a numerical value representing the substance’s ozone-depletion potential. In addition, the Administrator shall publish the chlorine and bromine loading potential and the atmospheric lifetime of each listed substance. One year after November 15, 1990 (one year after the addition of a substance to either of such lists in the case of a substance added after the publication of the initial lists of such substances), and after notice and opportunity for public comment, the Administrator shall publish the global warming potential of each listed substance. The preceding sentence shall not be construed to be the basis of any additional regulation under this chapter. In the case of the substances referred to in table 1, the ozone-depletion potential shall be as specified in table 1, unless the Administrator adjusts the substance’s ozone-depletion potential based on criteria referred to in section 7671(10) of this title:

Table 1
Substance Ozone- depletion potential
chlorofluorocarbon-11 (CFC-11) 1.0
chlorofluorocarbon-12 (CFC-12) 1.0
chlorofluorocarbon-13 (CFC-13) 1.0
chlorofluorocarbon-111 (CFC-111) 1.0
chlorofluorocarbon-112 (CFC-112) 1.0
chlorofluorocarbon-113 (CFC-113) 0.8
chlorofluorocarbon-114 (CFC-114) 1.0
chlorofluorocarbon-115 (CFC-115) 0.6
chlorofluorocarbon-211 (CFC-211) 1.0
chlorofluorocarbon-212 (CFC-212) 1.0
chlorofluorocarbon-213 (CFC-213) 1.0
chlorofluorocarbon-214 (CFC-214) 1.0
chlorofluorocarbon-215 (CFC-215) 1.0
chlorofluorocarbon-216 (CFC-216) 1.0
chlorofluorocarbon-217 (CFC-217) 1.0
halon-1211 3.0
halon-1301 10.0
halon-2402 6.0
carbon tetrachloride 1.1
methyl chloroform 0.1
hydrochlorofluorocarbon-22 (HCFC-22) 0.05
hydrochlorofluorocarbon-123 (HCFC-123) 0.02
hydrochlorofluorocarbon-124 (HCFC-124) 0.02
hydrochlorofluorocarbon-141(b) (HCFC-141(b)) 0.1
hydrochlorofluorocarbon-142(b) (HCFC-142(b)) 0.06

Where the ozone-depletion potential of a substance is specified in the Montreal Protocol, the ozone-depletion potential specified for that substance under this section shall be consistent with the Montreal Protocol.