§ 68.130 - List of substances.


Latest version.
  • § 68.130 List of substances.

    (a) Regulated toxic and flammable substances under section 112(r) of the Clean Air Act are the substances listed in Tables 1, 2, 3, and 4. Threshold quantities for listed toxic and flammable substances are specified in the tables.

    (b) The basis for placing toxic and flammable substances on the list of regulated substances are explained in the notes to the list.

    Table 1 to § 68.130 - List of Regulated Toxic Substances and Threshold Quantities for Accidental Release Prevention

    [Alphabetical Order - 77 Substances]

    Chemical name CAS No. Threshold quantity (lbs) Basis for listing
    Acrolein [2-Propenal]107-02-85,000b
    Acrylonitrile [2-Propenenitrile]107-13-120,000b
    Acrylyl chloride [2-Propenoyl chloride]814-68-65,000b
    Allyl alcohol [2-Propen-l-ol]107-18-61615,000b
    Allylamine [2-Propen-l-amine]107-11-910,000b
    Ammonia (anhydrous)7664-41-710,000a, b
    Ammonia (conc 20% or greater)7664-41-720,000a, b
    Arsenous trichloride7784-34-115,000b
    Arsine7784-42-11,000b
    Boron trichloride [Borane, trichloro-]10294-34-55,000b
    Boron trifluoride [Borane, trifluoro-]7637-07-25,000b
    Boron trifluoride compound with methyl ether (1:1) [Boron, trifluoro [oxybis [metane]]-, T-4-353-42-415,000b
    Bromine7726-95-610,000a, b
    Carbon disulfide75-15-020,000b
    Chlorine7782-50-52,500a, b
    Chlorine dioxide [Chlorine oxide (ClO2)]10049-04-41,000c
    Chloroform [Methane, trichloro-]67-66-320,000b
    Chloromethyl ether [Methane, oxybis[chloro-]542-88-11,000b
    Chloromethyl methyl ether [Methane, chloromethoxy-]107-30-25,000b
    Crotonaldehyde [2-Butenal]4170-30-320,000b
    Crotonaldehyde, (E)- [2-Butenal, (E)-]123-73-920,000b
    Cyanogen chloride506-77-410,000c
    Cyclohexylamine [Cyclohexanamine]108-91-815,000b
    Diborane19287-45-72,500b
    Dimethyldichlorosilane [Silane, dichlorodimethyl-]75-78-55,000b
    1,1-Dimethylhydrazine [Hydrazine, 1,1-dimethyl-]57-14-715,000b
    Epichlorohydrin [Oxirane, (chloromethyl)-]106-89-820,000b
    Ethylenediamine [1,2-Ethanediamine]107-15-320,000b
    Ethyleneimine [Aziridine]151-56-410,000b
    Ethylene oxide [Oxirane]75-21-810,000a, b
    Fluorine7782-41-41,000b
    Formaldehyde (solution)50-00-015,000b
    Furan110-00-95,000b
    Hydrazine302-01-215,000b
    Hydrochloric acid (conc 37% or greater)7647-01-015,000d
    Hydrocyanic acid74-90-82,500a, b
    Hydrogen chloride (anhydrous) [Hydrochloric acid]7647-01-05,000a
    Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid]7664-39-31,000a, b
    Hydrogen selenide7783-07-5500b
    Hydrogen sulfide7783-06-410,000a, b
    Iron, pentacarbonyl- [Iron carbonyl (Fe(CO)5), (TB-5-11)-]13463-40-62,500b
    Isobutyronitrile [Propanenitrile, 2-methyl-]78-82-020,000b
    Isopropyl chloroformate [Carbonochloridic acid, 1-methylethyl ester]108-23-615,000b
    Methacrylonitrile [2-Propenenitrile, 2-methyl-]126-98-710,000b
    Methyl chloride [Methane, chloro-]74-87-310,000a
    Methyl chloroformate [Carbonochloridic acid, methylester]79-22-15,000b
    Methyl hydrazine [Hydrazine, methyl-]60-34-415,000b
    Methyl isocyanate [Methane, isocyanato-]624-83-910,000a, b
    Methyl mercaptan [Methanethiol]74-93-110,000b
    Methyl thiocyanate [Thiocyanic acid, methyl ester]556-64-920,000b
    Methyltrichlorosilane [Silane, trichloromethyl-]75-79-65,000b
    Nickel carbonyl13463-39-31,000b
    Nitric acid (conc 80% or greater)7697-37-215,000b
    Nitric oxide [Nitrogen oxide (NO)]10102-43-910,000b
    Oleum (Fuming Sulfuric acid) [Sulfuric acid, mixture with sulfur trioxide]1 8014-95-710,000e
    Peracetic acid [Ethaneperoxoic acid]79-21-010,000b
    Perchloromethylmercaptan [Methanesulfenyl chloride, trichloro-]594-42-310,000b
    Phosgene [Carbonic dichloride]75-44-5500a, b
    Phosphine7803-51-25,000b
    Phosphorus oxychloride [Phosphoryl chloride]10025-87-35,000b
    Phosphorus trichloride [Phosphorous trichloride]7719-12-215,000b
    Piperidine110-89-415,000b
    Propionitrile [Propanenitrile]107-12-010,000b
    Propyl chloroformate [Carbonochloridic acid, propylester]109-61-515,000b
    Propyleneimine [Aziridine, 2-methyl-]75-55-810,000b
    Propylene oxide [Oxirane, methyl-]75-56-910,000b
    Sulfur dioxide (anhydrous)7446-09-55,000a, b
    Sulfur tetrafluoride [Sulfur fluoride (SF4), (T-4)-]7783-60-02,500b
    Sulfur trioxide7446-11-910,000a, b
    Tetramethyllead [Plumbane, tetramethyl-]75-74-110,000b
    Tetranitromethane [Methane, tetranitro-]509-14-810,000b
    Titanium tetrachloride [Titanium chloride (TiCl4) (T-4)-]7550-45-02,500b
    Toluene 2,4-diisocyanate [Benzene, 2,4-diisocyanato-1-methyl-]1 584-84-910,000a
    Toluene 2,6-diisocyanate [Benzene, 1,3-diisocyanato-2-methyl-]1 91-08-710,000a
    Toluene diisocyanate (unspecified isomer) [Benzene, 1,3-diisocyanatomethyl-]1 26471-62-510,000a
    Trimethylchlorosilane [Silane, chlorotrimethyl-]75-77-410,000b
    Vinyl acetate monomer [Acetic acid ethenyl ester]108-05-415,000b

    Table 2 to § 68.130 - List of Regulated Toxic Substances and Threshold Quantities for Accidental Release Prevention

    [CAS Number Order - 77 Substances]

    CAS No. Chemical name Threshold quantity (lbs) Basis for listing
    50-00-0Formaldehyde (solution)15,000b
    57-14-71,1-Dimethylhydrazine [Hydrazine, 1,1-dimethyl-]15,000b
    60-34-4Methyl hydrazine [Hydrazine, methyl-]15,000b
    67-66-3Chloroform [Methane, trichloro-]20,000b
    74-87-3Methyl chloride [Methane, chloro-]10,000a
    74-90-8Hydrocyanic acid2,500a, b
    74-93-1Methyl mercaptan [Methanethiol]10,000b
    75-15-0Carbon disulfide20,000b
    75-21-8Ethylene oxide [Oxirane]10,000a, b
    75-44-5Phosgene [Carbonic dichloride]500a, b
    75-55-8Propyleneimine [Aziridine, 2-methyl-]10,000b
    75-56-9Propylene oxide [Oxirane, methyl-]10,000b
    75-74-1Tetramethyllead [Plumbane, tetramethyl-]10,000b
    75-77-4Trimethylchlorosilane [Silane, chlorotrimethyl-]10,000b
    75-78-5Dimethyldichlorosilane [Silane, dichlorodimethyl-]5,000b
    75-79-6Methyltrichlorosilane [Silane, trichloromethyl-]5,000b
    78-82-0Isobutyronitrile [Propanenitrile, 2-methyl-]20,000b
    79-21-0Peracetic acid [Ethaneperoxoic acid]10,000b
    79-22-1Methyl chloroformate [Carbonochloridic acid, methylester]5,000b
    91-08-7Toluene 2,6-diisocyanate [Benzene, 1,3-diisocyanato-2-methyl-]1 10,000a
    106-89-8Epichlorohydrin [Oxirane, (chloromethyl)-]20,000b
    107-02-8Acrolein [2-Propenal]5,000b
    107-11-9Allylamine [2-Propen-1-amine]10,000b
    107-12-0Propionitrile [Propanenitrile]10,000b
    107-13-1Acrylonitrile [2-Propenenitrile]20,000b
    107-15-3Ethylenediamine [1,2-Ethanediamine]20,000b
    107-18-6Allyl alcohol [2-Propen-1-ol]15,000b
    107-30-2Chloromethyl methyl ether [Methane, chloromethoxy-]5,000b
    108-05-4Vinyl acetate monomer [Acetic acid ethenyl ester]15,000b
    108-23-6Isopropyl chloroformate [Carbonochloridic acid, 1-methylethyl ester]15,000b
    108-91-8Cyclohexylamine [Cyclohexanamine]15,000b
    109-61-5Propyl chloroformate [Carbonochloridic acid, propylester]15,000b
    110-00-9Furan5,000b
    110-89-4Piperidine15,000b
    123-73-9Crotonaldehyde, (E)- [2-Butenal, (E)-]20,000b
    126-98-7Methacrylonitrile [2-Propenenitrile, 2-methyl-]10,000b
    151-56-4Ethyleneimine [Aziridine]10,000b
    302-01-2Hydrazine15,000b
    353-42-4Boron trifluoride compound with methyl ether (1:1) [Boron, trifluoro[oxybis[methane]]-, T-4-15,000b
    506-77-4Cyanogen chloride10,000c
    509-14-8Tetranitromethane [Methane, tetranitro-]10,000b
    542-88-1Chloromethyl ether [Methane, oxybis[chloro-]1,000b
    556-64-9Methyl thiocyanate [Thiocyanic acid, methyl ester]20,000b
    584-84-9Toluene 2,4-diisocyanate [Benzene, 2,4-diisocyanato-1-methyl-]1 10,000a
    594-42-3Perchloromethylmercaptan [Methanesulfenyl chloride, trichloro-]10,000b
    624-83-9Methyl isocyanate [Methane, isocyanato-]10,000a, b
    814-68-6Acrylyl chloride [2-Propenoyl chloride]5,000b
    4170-30-3Crotonaldehyde [2-Butenal]20,000b
    7446-09-5Sulfur dioxide (anhydrous)5,000a, b
    7446-11-9Sulfur trioxide10,000a, b
    7550-45-0Titanium tetrachloride [Titanium chloride (TiCl4) (T-4)-]2,500b
    7637-07-2Boron trifluoride [Borane, trifluoro-]5,000b
    7647-01-0Hydrochloric acid (conc 37% or greater)15,000d
    7647-01-0Hydrogen chloride (anhydrous) [Hydrochloric acid]5,000a
    7664-39-3Hydrogen fluoride/Hydrofluoric acid (conc 50% or greater) [Hydrofluoric acid]1,000a, b
    7664-41-7Ammonia (anhydrous)10,000a, b
    7664-41-7Ammonia (conc 20% or greater)20,000a, b
    7697-37-2Nitric acid (conc 80% or greater)15,000b
    7719-12-2Phosphorus trichloride [Phosphorous trichloride]15,000b
    7726-95-6Bromine10,000a, b
    7782-41-4Fluorine1,000b
    7782-50-5Chlorine2,500a, b
    7783-06-4Hydrogen sulfide10,000a, b
    7783-07-5Hydrogen selenide500b
    7783-60-0Sulfur tetrafluoride [Sulfur fluoride (SF4), (T-4)-]2,500b
    7784-34-1Arsenous trichloride15,000b
    7784-42-1Arsine1,000b
    7803-51-2Phosphine5,000b
    8014-95-7Oleum (Fuming Sulfuric acid) [Sulfuric acid, mixture with sulfur trioxide]1 10,000e
    10025-87-3Phosphorus oxychloride [Phosphoryl chloride]5,000b
    10049-04-4Chlorine dioxide [Chlorine oxide (ClO2)]1,000c
    10102-43-9Nitric oxide [Nitrogen oxide (NO)]10,000b
    10294-34-5Boron trichloride [Borane, trichloro-]5,000b
    13463-39-3Nickel carbonyl1,000b
    13463-40-6Iron, pentacarbonyl- [Iron carbonyl (Fe(CO)5), (TB-5-11)-]2,500b
    19287-45-7Diborane2,500b
    26471-62-5Toluene diisocyanate (unspecified isomer) [Benzene, 1,3-diisocyanatomethyl-1]1 10,000a

    Table 3 to § 68.130 - List of Regulated Flammable Substances1 and Threshold Quantities for Accidental Release Prevention

    [Alphabetical Order - 63 Substances]

    Chemical name CAS No. Threshold quantity (lbs) Basis for listing
    Acetaldehyde75-07-010,000g
    Acetylene [Ethyne]74-86-210,000f
    Bromotrifluorethylene [Ethene, bromotrifluoro-]598-73-210,000f
    1,3-Butadiene106-99-010,000f
    Butane106-97-810,000f
    1-Butene106-98-910,000f
    2-Butene107-01-710,000f
    Butene25167-67-310,000f
    2-Butene-cis590-18-110,000f
    2-Butene-trans [2-Butene, (E)]624-64-610,000f
    Carbon oxysulfide [Carbon oxide sulfide (COS)]463-58-110,000f
    Chlorine monoxide [Chlorine oxide]7791-21-110,000f
    2-Chloropropylene [1-Propene, 2-chloro-]557-98-210,000g
    1-Chloropropylene [1-Propene, 1-chloro-]590-21-610,000g
    Cyanogen [Ethanedinitrile]460-19-510,000f
    Cyclopropane75-19-410,000f
    Dichlorosilane [Silane, dichloro-]4109-96-010,000f
    Difluoroethane [Ethane, 1,1-difluoro-]75-37-610,000f
    Dimethylamine [Methanamine, N-methyl-]124-40-310,000f
    2,2-Dimethylpropane [Propane, 2,2-dimethyl-]463-82-110,000f
    Ethane74-84-010,000f
    Ethyl acetylene [1-Butyne]107-00-610,000f
    Ethylamine [Ethanamine]75-04-710,000f
    Ethyl chloride [Ethane, chloro-]75-00-310,000f
    Ethylene [Ethene]74-85-110,000f
    Ethyl ether [Ethane, 1,1′-oxybis-]60-29-710,000g
    Ethyl mercaptan [Ethanethiol]75-08-110,000g
    Ethyl nitrite [Nitrous acid, ethyl ester]109-95-510,000f
    Hydrogen1333-74-010,000f
    Isobutane [Propane, 2-methyl]75-28-510,000f
    Isopentane [Butane, 2-methyl-]78-78-410,000g
    Isoprene [1,3-Butadinene, 2-methyl-]78-79-510,000g
    Isopropylamine [2-Propanamine]75-31-010,000g
    Isopropyl chloride [Propane, 2-chloro-]75-29-610,000g
    Methane74-82-810,000f
    Methylamine [Methanamine]74-89-510,000f
    3-Methyl-1-butene563-45-110,000f
    2-Methyl-1-butene563-46-210,000g
    Methyl ether [Methane, oxybis-]115-10-610,000f
    Methyl formate [Formic acid, methyl ester]107-31-310,000g
    2-Methylpropene [1-Propene, 2-methyl-]115-11-710,000f
    1,3-Pentadinene504-60-910,000f
    Pentane109-66-010,000g
    1-Pentene109-67-110,000g
    2-Pentene, (E)-646-04-810,000g
    2-Pentene, (Z)-627-20-310,000g
    Propadiene [1,2-Propadiene]463-49-010,000f
    Propane74-98-610,000f
    Propylene [1-Propene]115-07-110,000f
    Propyne [1-Propyne]74-99-710,000f
    Silane7803-62-510,000f
    Tetrafluoroethylene [Ethene, tetrafluoro-]116-14-310,000f
    Tetramethylsilane [Silane, tetramethyl-]75-76-310,000g
    Trichlorosilane [Silane, trichloro-]10025-78-210,000g
    Trifluorochloroethylene [Ethene, chlorotrifluoro-]79-38-910,000f
    Trimethylamine [Methanamine, N,N-dimethyl-]75-50-310,000f
    Vinyl acetylene [1-Buten-3-yne]689-97-410,000f
    Vinyl chloride [Ethene, chloro-]75-01-410,000a, f
    Vinyl ethyl ether [Ethene, ethoxy-]109-92-210,000g
    Vinyl fluoride [Ethene, fluoro-]75-02-510,000f
    Vinylidene chloride [Ethene, 1,1-dichloro-]75-35-410,000g
    Vinylidene fluoride [Ethene, 1,1-difluoro-]75-38-710,000f
    Vinyl methyl ether [Ethene, methoxy-]107-25-510,000f

    Table 4 to § 68.130 - List of Regulated Flammable Substances1 and Threshold Quantities for Accidental Release Prevention

    [CAS Number Order - 63 Substances]

    CAS No. Chemical name CAS No. Threshold quantity
    (lbs)
    Basis for listing
    60-29-7Ethyl ether [Ethane, 1,1′-oxybis-]60-29-710,000g
    74-82-8Methane74-82-810,000f
    74-84-0Ethane74-84-010,000f
    74-85-1Ethylene [Ethene]74-85-110,000f
    74-86-2Acetylene [Ethyne]74-86-210,000f
    74-89-5Methylamine [Methanamine]74-89-510,000f
    74-98-6Propane74-98-610,000f
    74-99-7Propyne [1-Propyne]74-99-710,000f
    75-00-3Ethyl chloride [Ethane, chloro-]75-00-310,000f
    75-01-4Vinyl chloride [Ethene, chloro-]75-01-410,000a, f
    75-02-5Vinyl fluoride [Ethene, fluoro-]75-02-510,000f
    75-04-7Ethylamine [Ethanamine]75-04-710,000f
    75-07-0Acetaldehyde75-07-010,000g
    75-08-1Ethyl mercaptan [Ethanethiol]75-08-110,000g
    75-19-4Cyclopropane75-19-410,000f
    75-28-5Isobutane [Propane, 2-methyl]75-28-510,000f
    75-29-6Isopropyl chloride [Propane, 2-chloro-]75-29-610,000g
    75-31-0Isopropylamine [2-Propanamine]75-31-010,000g
    75-35-4Vinylidene chloride [Ethene, 1,1-dichloro-]75-35-410,000g
    75-37-6Difluoroethane [Ethane, 1,1-difluoro-]75-37-610,000f
    75-38-7Vinylidene fluoride [Ethene, 1,1-difluoro-]75-38-710,000f
    75-50-3Trimethylamine [Methanamine, N, N-dimethyl-]75-50-310,000f
    75-76-3Tetramethylsilane [Silane, tetramethyl-]75-76-310,000g
    78-78-4Isopentane [Butane, 2-methyl-]78-78-410,000g
    78-79-5Isoprene [1,3,-Butadiene, 2-methyl-]78-79-510,000g
    79-38-9Trifluorochloroethylene [Ethene, chlorotrifluoro-]79-38-910,000f
    106-97-8Butane106-97-810,000f
    106-98-91-Butene106-98-910,000f
    196106-99-01,3-Butadiene106-99-010,000f
    107-00-6Ethyl acetylene [1-Butyne]107-00-610,000f
    107-01-72-Butene107-01-710,000f
    107-25-5Vinyl methyl ether [Ethene, methoxy-]107-25-510,000f
    107-31-3Methyl formate [Formic acid, methyl ester]107-31-310,000g
    109-66-0Pentane109-66-010,000g
    109-67-11-Pentene109-67-110,000g
    109-92-2Vinyl ethyl ether [Ethene, ethoxy-]109-92-210,000g
    109-95-5Ethyl nitrite [Nitrous acid, ethyl ester]109-95-510,000f
    115-07-1Propylene [1-Propene]115-07-110,000f
    115-10-6Methyl ether [Methane, oxybis-]115-10-610,000f
    115-11-72-Methylpropene [1-Propene, 2-methyl-]115-11-710,000f
    116-14-3Tetrafluoroethylene [Ethene, tetrafluoro-]116-14-310,000f
    124-40-3Dimethylamine [Methanamine, N-methyl-]124-40-310,000f
    460-19-5Cyanogen [Ethanedinitrile]460-19-510,000f
    463-49-0Propadiene [1,2-Propadiene]463-49-010,000f
    463-58-1Carbon oxysulfide [Carbon oxide sulfide (COS)]463-58-110,000f
    463-82-12,2-Dimethylpropane [Propane, 2,2-dimethyl-]463-82-110,000f
    504-60-91,3-Pentadiene504-60-910,000f
    557-98-22-Chloropropylene [1-Propene, 2-chloro-]557-98-210,000g
    563-45-13-Methyl-1-butene563-45-110,000f
    563-46-22-Methyl-1-butene563-46-210,000g
    590-18-12-Butene-cis590-18-110,000f
    590-21-61-Chloropropylene [1-Propene, 1-chloro-]590-21-610,000g
    598-73-2Bromotrifluorethylene [Ethene, bromotrifluoro-]598-73-210,000f
    624-64-62-Butene-trans [2-Butene, (E)]624-64-610,000f
    627-20-32-Pentene, (Z)-627-20-310,000g
    646-04-82-Pentene, (E)-646-04-810,000g
    689-97-4Vinyl acetylene [1-Buten-3-yne]689-97-410,000f
    1333-74-0Hydrogen1333-74-010,000f
    4109-96-0Dichlorosilane [Silane, dichloro-]4109-96-010,000f
    7791-21-1Chlorine monoxide [Chlorine oxide]7791-21-110,000f
    7803-62-5Silane7803-62-510,000f
    10025-78-2Trichlorosilane [Silane, trichloro-]10025-78-210,000g
    25167-67-3Butene25167-67-310,000f

    [59 FR 4493, Jan. 31, 1994. Redesignated at 61 FR 31717, June 20, 1996, as amended at 62 FR 45132, Aug. 25, 1997; 63 FR 645, Jan. 6, 1998; 65 FR 13250, Mar. 13, 2000; 82 FR 4702, Jan. 13, 2017]