Chemical Name CAS # Threshold Quantity (lbs) Basis for Listing
Acetaldehyde 75-07-0 10,000 g
Acetylene [Ethyne] 74-86-2 10,000 f
Bromotrifluorethylene [Ethene, bromotrifluoro-] 598-73-2 10,000 f
1,3-Butadiene 106-99-0 10,000 f
Butane 106-97-8 10,000 f
1-Butene 106-98-9 10,000 f
2-Butene 107-01-7 10,000 f
Butene 25167-67-3 10,000 f
2-Butene-cis 590-18-1 10,000 f
2-Butene-trans [2-Butene, (E)] 624-64-6 10,000 f
Carbon oxysulfide [Carbon oxide sulfide (COS)] 463-58-1 10,000 f
Chlorine monoxide [Chlorine oxide] 7791-21-1 10,000 f
2-Chloropropylene [1-Propene, 2-chloro-] 557-98-2 10,000 g
1-Chloropropylene [1-Propene, 1-chloro-] 590-21-6 10,000 g
Cyanogen [Ethanedinitrile] 460-19-5 10,000 f
Cyclopropane 75-19-4 10,000 f
Dichlorosilane [Silane, dichloro-] 4109-96-0 10,000 f
Difluoroethane [Ethane, 1,1-difluoro-] 75-37-6 10,000 f
Dimethylamine [Methanamine, N-methyl-] 124-40-3 10,000 f
2,2-Dimethylpropane [Propane, 2,2-dimethyl-] 463-82-1 10,000 f
Ethane 74-84-0 10,000 f
Ethyl acetylene [1-Butyne] 107-00-6 10,000 f
Ethylamine [Ethanamine] 75-04-7 10,000 f
Ethyl chloride [Ethane, chloro-] 75-00-3 10,000 f
Ethylene [Ethene] 74-85-1 10,000 f
Ethyl ether [Ethane, 1,1'-oxybis-] 60-29-7 10,000 g
Ethyl mercaptan [Ethanethiol] 75-08-1 10,000 g
Ethyl nitrite [Nitrous acid, ethyl ester] 109-95-5 10,000 f
Hydrogen 1333-74-0 10,000 f
Isobutane [Propane, 2-methyl] 75-28-5 10,000 f
Isopentane [Butane, 2-methyl-] 78-78-4 10,000 g
Isoprene [1,3-Butadiene, 2-methyl-] 78-79-5 10,000 g
Isopropylamine [2-Propanamine] 75-31-0 10,000 g
Isopropyl chloride [Propane, 2-chloro-] 75-29-6 10,000 g
Methane 74-82-8 10,000 f
Methylamine [Methanamine] 74-89-5 10,000 f
3-Methyl-1-butene 563-45-1 10,000 f
2-Methyl-1-butene 563-46-2 10,000 g
Methyl ether [Methane, oxybis-] 115-10-6 10,000 f
Methyl formate [Formic acid, methyl ester] 107-31-3 10,000 g
2-Methylpropene [1-Propene, 2-methyl-] 115-11-7 10,000 f
1,3-Pentadiene 504-60-9 10,000 f
Pentane 109-66-0 10,000 g
1-Pentene 109-67-1 10,000 g
2-Pentene, (E)- 646-04-8 10,000 g
2-Pentene, (Z)- 627-20-3 10,000 g
Propadiene [1,2-Propadiene] 463-49-0 10,000 f
Propane 74-98-6 10,000 f
Propylene [1-Propene] 115-07-1 10,000 f
Propyne [1-Propyne] 74-99-7 10,000 f
Silane 7803-62-5 10,000 f
Tetrafluoroethylene [Ethene, tetrafluoro-] 116-14-3 10,000 f
Tetramethylsilane [Silane, tetramethyl-] 75-76-3 10,000 g
Trichlorosilane [Silane, trichloro-] 10025-78-2 10,000 g
Trifluorochloroethylene [Ethene, chlorotrifluoro-] 79-38-9 10,000 f
Trimethylamine [Methanamine, N,N-dimethyl-] 75-50-3 10,000 f
Vinyl acetylene [1-Buten-3-yne] 689-97-4 10,000 f
Vinyl chloride [Ethene, chloro-] 75-01-4 10,000 a, f
Vinyl ethyl ether [Ethene, ethoxy-] 109-92-2 10,000 g
Vinyl fluoride [Ethene, fluoro-] 75-02-5 10,000 f
Vinylidene chloride [Ethene, 1,1-dichloro-] 75-35-4 10,000 g
Vinylidene fluoride [Ethene, 1,1-difluoro-] 75-38-7 10,000 f
Vinyl methyl ether [Ethene, methoxy-] 107-25-5 10,000 f

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

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