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

Basis for Listing:

  1. Mandated for listing by Congress
  2. On EHS list, vapor pressure 10 mmHg or greater
  3. Toxic gas
  4. Toxicity of hydrogen chloride, potential to release hydrogen chloride, & history of accidents
  5. Toxicity of sulfur trioxide and sulfuric acid, potential to release sulfur trioxide, & history of accidents
  6. Flammable gas
  7. Volatile flammable liquid

1 The mixture exemption in 40 CFR 68.115(b)(1) does not apply to the substance.

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