{"data":{"id":"us/40-cfr-appendix-b-to-part-355","jurisdiction":"us","citation":"40 CFR Appendix B to Part 355","heading":"Appendix B to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities","body":"[CAS Number Order]\nCAS No. Chemical name Notes Reportable quantity * (pounds) Threshold planning quantity (pounds)\n0 Organorhodium Complex (PMN-82-147) 10 10/10,000\n50-00-0 Formaldehyde f 100 500\n50-07-7 Mitomycin C 10 500/10,000\n50-14-6 Ergocalciferol b 1,000 1,000/10,000\n51-21-8 Fluorouracil 500 500/10,000\n51-75-2 Mechlorethamine b 10 10\n51-83-2 Carbachol Chloride 500 500/10,000\n54-11-5 Nicotine b 100 100\n54-62-6 Aminopterin 500 500/10,000\n55-91-4 Isofluorphate b 100 100\n56-25-7 Cantharidin 100 100/10,000\n56-38-2 Parathion b 10 100\n56-72-4 Coumaphos 10 100/10,000\n57-14-7 Dimethylhydrazine 10 1,000\n57-24-9 Strychnine b 10 100/10,000\n57-47-6 Physostigmine 100 100/10,000\n57-57-8 Propiolactone, Beta- 10 500\n57-64-7 Physostigmine, Salicylate (1:1) 100 100/10,000\n57-74-9 Chlordane 1 1,000\n58-36-6 Phenoxarsine, 10,10′-Oxydi- 500 500/10,000\n58-89-9 Lindane 1 1,000/10,000\n59-88-1 Phenylhydrazine Hydrochloride 1,000 1,000/10,000\n60-34-4 Methyl Hydrazine 10 500\n60-41-3 Strychnine sulfate 10 100/10,000\n60-51-5 Dimethoate 10 500/10,000\n62-38-4 Phenylmercury Acetate 100 500/10,000\n62-53-3 Aniline f 5,000 1,000\n62-73-7 Dichlorvos 10 1,000\n62-74-8 Sodium Fluoroacetate 10 10/10,000\n62-75-9 Nitrosodimethylamine d 10 1,000\n64-00-6 Phenol, 3-(1-Methylethyl)-, Methylcarbamate 10 500/10,000\n64-86-8 Colchicine d 10 10/10,000\n65-30-5 Nicotine sulfate 100 100/10,000\n66-81-9 Cycloheximide 100 100/10,000\n67-66-3 Chloroform f 10 10,000\n70-69-9 Propiophenone, 4-Amino- c 100 100/10,000\n71-63-6 Digitoxin b 100 100/10,000\n72-20-8 Endrin 1 500/10,000\n74-83-9 Methyl Bromide f 1,000 1,000\n74-90-8 Hydrocyanic Acid 10 100\n74-93-1 Methyl Mercaptan f 100 500\n75-15-0 Carbon Disulfide f 100 10,000\n75-21-8 Ethylene Oxide f 10 1,000\n75-44-5 Phosgene f 10 10\n75-55-8 Propyleneimine 1 10,000\n75-56-9 Propylene Oxide f 100 10,000\n75-74-1 Tetramethyllead b, f 100 100\n75-77-4 Trimethylchlorosilane 1,000 1,000\n75-78-5 Dimethyldichlorosilane d 500 500\n75-79-6 Methyltrichlorosilane d 500 500\n75-86-5 Acetone Cyanohydrin 10 1,000\n76-02-8 Trichloroacetyl Chloride 500 500\n77-47-4 Hexachlorocyclopentadiene d 10 100\n77-78-1 Dimethyl Sulfate 100 500\n77-81-6 Tabun b, d 10 10\n78-00-2 Tetraethyllead b 10 100\n78-34-2 Dioxathion 500 500\n78-53-5 Amiton 500 500\n78-71-7 Oxetane, 3,3-Bis(Chloromethyl)- 500 500\n78-82-0 Isobutyronitrile d 1,000 1,000\n78-94-4 Methyl Vinyl Ketone 10 10\n78-97-7 Lactonitrile 1,000 1,000\n79-06-1 Acrylamide f 5,000 1,000/10,000\n79-11-8 Chloroacetic Acid 100 100/10,000\n79-19-6 Thiosemicarbazide 100 100/10,000\n79-21-0 Peracetic Acid 500 500\n79-22-1 Methyl Chloroformate d 1,000 500\n80-63-7 Methyl 2-Chloroacrylate 500 500\n81-81-2 Warfarin 100 500/10,000\n82-66-6 Diphacinone 10 10/10,000\n86-50-0 Azinphos-Methyl 1 10/10,000\n86-88-4 ANTU 100 500/10,000\n88-05-1 Aniline, 2,4,6-Trimethyl- 500 500\n88-85-7 Dinoseb 1,000 100/10,000\n91-08-7 Toluene 2,6-Diisocyanate 100 100\n95-48-7 Cresol, o- 100 1,000/10,000\n98-05-5 Benzenearsonic Acid 10 10/10,000\n98-07-7 Benzotrichloride 10 100\n98-13-5 Trichlorophenylsilane d 500 500\n98-16-8 Benzenamine, 3-(Trifluoromethyl)- 500 500\n98-87-3 Benzal Chloride 5,000 500\n98-95-3 Nitrobenzene f 1,000 10,000\n99-98-9 Dimethyl-p-Phenylenediamine 10 10/10,000\n100-14-1 Benzene, 1-(Chloromethyl)-4-Nitro- 500 500/10,000\n100-44-7 Benzyl Chloride 100 500\n102-36-3 Isocyanic Acid, 3,4-Dichlorophenyl Ester 500 500/10,000\n103-85-5 Phenylthiourea 100 100/10,000\n106-89-8 Epichlorohydrin f 100 1,000\n106-96-7 Propargyl Bromide 10 10\n107-02-8 Acrolein 1 500\n107-07-3 Chloroethanol 500 500\n107-11-9 Allylamine 500 500\n107-12-0 Propionitrile 10 500\n107-13-1 Acrylonitrile f 100 10,000\n107-15-3 Ethylenediamine 5,000 10,000\n107-16-4 Formaldehyde Cyanohydrin d 1,000 1,000\n107-18-6 Allyl Alcohol 100 1,000\n107-30-2 Chloromethyl Methyl Ether b 10 100\n107-44-8 Sarin d 10 10\n107-49-3 TEPP 10 100\n108-05-4 Vinyl Acetate Monomer f 5,000 1,000\n108-23-6 Isopropyl Chloroformate 1,000 1,000\n108-91-8 Cyclohexylamine f 10,000 10,000\n108-95-2 Phenol 1,000 500/10,000\n108-98-5 Thiophenol 100 500\n109-61-5 Propyl Chloroformate 500 500\n109-77-3 Malononitrile 1,000 500/10,000\n110-00-9 Furan 100 500\n110-57-6 Trans-1,4-Dichlorobutene 500 500\n110-89-4 Piperidine 1,000 1,000\n111-44-4 Dichloroethyl Ether 10 10,000\n111-69-3 Adiponitrile f 1,000 1,000\n115-21-9 Trichloroethylsilane d 500 500\n115-26-4 Dimefox 500 500\n115-29-7 Endosulfan 1 10/10,000\n115-90-2 Fensulfothion d 500 500\n116-06-3 Aldicarb b 1 100/10,000\n119-38-0 Isopropylmethyl-pyrazolyl Dimethylcarbamate 100 500\n123-31-9 Hydroquinone f 100 500/10,000\n123-73-9 Crotonaldehyde, (E)- 100 1,000\n124-65-2 Sodium Cacodylate 100 100/10,000\n124-87-8 Picrotoxin 500 500/10,000\n126-98-7 Methacrylonitrile d 1,000 500\n129-00-0 Pyrene b 5,000 1,000/10,000\n129-06-6 Warfarin Sodium d 100 100/10,000\n140-29-4 Benzyl Cyanide d 500 500\n140-76-1 Pyridine, 2-Methyl-5-Vinyl- 500 500\n141-66-2 Dicrotophos 100 100\n143-33-9 Sodium Cyanide (Na(CN)) a 10 100\n144-49-0 Fluoroacetic Acid 10 10/10,000\n149-74-6 Dichloromethylphenylsilane 1,000 1,000\n151-38-2 Methoxyethylmercuric Acetate 500 500/10,000\n151-50-8 Potassium Cyanide a 10 100\n151-56-4 Ethyleneimine 1 500\n152-16-9 Diphosphoramide, Octamethyl- 100 100\n297-78-9 Isobenzan 100 100/10,000\n297-97-2 Thionazin 100 500\n298-00-0 Parathion-Methyl b 100 100/10,000\n298-02-2 Phorate 10 10\n298-04-4 Disulfoton 1 500\n300-62-9 Amphetamine 1,000 1,000\n302-01-2 Hydrazine 1 1,000\n309-00-2 Aldrin 1 500/10,000\n315-18-4 Mexacarbate 1,000 500/10,000\n316-42-7 Emetine, Dihydrochloride d 1 1/10,000\n327-98-0 Trichloronate e 500 500\n353-42-4 Boron Trifluoride Compound With Methyl Ether (1:1) 1,000 1,000\n359-06-8 Fluoroacetyl Chloride b 10 10\n371-62-0 Ethylene Fluorohydrin b, d 10 10\n379-79-3 Ergotamine Tartrate 500 500/10,000\n465-73-6 Isodrin 1 100/10,000\n470-90-6 Chlorfenvinfos 500 500\n502-39-6 Methylmercuric Dicyanamide 500 500/10,000\n504-24-5 Pyridine, 4-Amino- d 1,000 500/10,000\n505-60-2 Mustard Gas d 500 500\n506-61-6 Potassium Silver Cyanide a 1 500\n506-68-3 Cyanogen Bromide 1,000 500/10,000\n506-78-5 Cyanogen Iodide 1,000 1,000/10,000\n509-14-8 Tetranitromethane 10 500\n514-73-8 Dithiazanine Iodide 500 500/10,000\n534-07-6 Bis(Chloromethyl) Ketone 10 10/10,000\n534-52-1 Dinitrocresol 10 10/10,000\n535-89-7 Crimidine 100 100/10,000\n538-07-8 Ethylbis(2-Chloroethyl)Amine d 500 500\n541-25-3 Lewisite b, d 10 10\n541-53-7 Dithiobiuret 100 100/10,000\n542-76-7 Propionitrile, 3-Chloro- 1,000 1,000\n542-88-1 Chloromethyl Ether d 10 100\n542-90-5 Ethylthiocyanate 10,000 10,000\n555-77-1 Tris(2-Chloroethyl)Amine d 100 100\n556-61-6 Methyl Isothiocyanate a 500 500\n556-64-9 Methyl Thiocyanate 10,000 10,000\n558-25-8 Methanesulfonyl Fluoride 1,000 1,000\n563-12-2 Ethion 10 1,000\n563-41-7 Semicarbazide Hydrochloride 1,000 1,000/10,000\n584-84-9 Toluene 2,4-Diisocyanate 100 500\n594-42-3 Perchloromethylmercaptan 100 500\n597-64-8 Tetraethyltin b 100 100\n614-78-8 Thiourea, (2-Methylphenyl)- 500 500/10,000\n624-83-9 Methyl Isocyanate 10 500\n627-11-2 Chloroethyl Chloroformate 1,000 1,000\n630-60-4 Ouabain b 100 100/10,000\n639-58-7 Triphenyltin Chloride 500 500/10,000\n640-19-7 Fluoroacetamide 100 100/10,000\n644-64-4 Dimetilan 1 500/10,000\n675-14-9 Cyanuric Fluoride 100 100\n676-97-1 Methyl Phosphonic Dichloride a 100 100\n696-28-6 Phenyl Dichloroarsine d 1 500\n760-93-0 Methacrylic Anhydride 500 500\n786-19-6 Carbophenothion 500 500\n814-49-3 Diethyl Chlorophosphate d 500 500\n814-68-6 Acrylyl Chloride d 100 100\n824-11-3 Trimethylolpropane Phosphite d 100 100/10,000\n900-95-8 Stannane, Acetoxytriphenyl- c 500 500/10,000\n919-86-8 Demeton-S-Methyl 500 500\n920-46-7 Methacryloyl Chloride 100 100\n944-22-9 Fonofos 500 500\n947-02-4 Phosfolan 100 100/10,000\n950-10-7 Mephosfolan 500 500\n950-37-8 Methidathion 500 500/10,000\n991-42-4 Norbormide 100 100/10,000\n998-30-1 Triethoxysilane 500 500\n999-81-5 Chlormequat Chloride d 100 100/10,000\n1031-47-6 Triamiphos 500 500/10,000\n1066-45-1 Trimethyltin Chloride 500 500/10,000\n1122-60-7 Nitrocyclohexane 500 500\n1124-33-0 Pyridine, 4-Nitro-,1-Oxide 500 500/10,000\n1129-41-5 Metolcarb 1,000 100/10,000\n1303-28-2 Arsenic Pentoxide 1 100/10,000\n1306-19-0 Cadmium Oxide 100 100/10,000\n1314-62-1 Vanadium Pentoxide 1,000 100/10,000\n1314-84-7 Zinc Phosphide a 100 500\n1327-53-3 Arsenous Oxide d 1 100/10,000\n1397-94-0 Antimycin A b 1,000 1,000/10,000\n1420-07-1 Dinoterb 500 500/10,000\n1464-53-5 Diepoxybutane 10 500\n1558-25-4 Trichloro(Chloromethyl)Silane 100 100\n1563-66-2 Carbofuran 10 10/10,000\n1600-27-7 Mercuric Acetate 500 500/10,000\n1622-32-8 Ethanesulfonyl Chloride, 2-Chloro- 500 500\n1752-30-3 Acetone Thiosemicarbazide 1,000 1,000/10,000\n1910-42-5 Paraquat Dichloride 10 10/10,000\n1982-47-4 Chloroxuron 500 500/10,000\n2001-95-8 Valinomycin b 1,000 1,000/10,000\n2032-65-7 Methiocarb 10 500/10,000\n2074-50-2 Paraquat Methosulfate 10 10/10,000\n2097-19-0 Phenylsilatrane d 100 100/10,000\n2104-64-5 EPN 100 100/10,000\n2223-93-0 Cadmium Stearate b 1,000 1,000/10,000\n2231-57-4 Thiocarbazide 1,000 1,000/10,000\n2238-07-5 Diglycidyl Ether 1,000 1,000\n2275-18-5 Prothoate 100 100/10,000\n2497-07-6 Oxydisulfoton d 500 500\n2524-03-0 Dimethyl Phosphorochloridothioate 500 500\n2540-82-1 Formothion 100 100\n2570-26-5 Pentadecylamine 100 100/10,000\n2587-90-8 Phosphorothioic Acid, O,O-Dimethyl-S-(2-Methylthio) Ethyl Ester b, c 500 500\n2631-37-0 Promecarb d 1,000 500/10,000\n2636-26-2 Cyanophos 1,000 1,000\n2642-71-9 Azinphos-Ethyl 100 100/10,000\n2665-30-7 Phosphonothioic Acid, Methyl-, O-(4-Nitrophenyl) O-Phenyl Ester 500 500\n2703-13-1 Phosphonothioic Acid, Methyl-, O-Ethyl O-(4-(Methylthio)Phenyl) Ester 500 500\n2757-18-8 Thallous Malonate b, d 100 100/10,000\n2763-96-4 Muscimol 1,000 500/10,000\n2778-04-3 Endothion 500 500/10,000\n3037-72-7 Silane, (4-Aminobutyl)Diethoxymethyl- 1,000 1,000\n3254-63-5 Phosphoric Acid, Dimethyl 4-(Methylthio)Phenyl Ester 500 500\n3569-57-1 Sulfoxide, 3-Chloropropyl Octyl 500 500\n3615-21-2 Benzimidazole, 4,5-Dichloro-2-(Trifluoromethyl)- c 500 500/10,000\n3689-24-5 Sulfotep 100 500\n3691-35-8 Chlorophacinone 100 100/10,000\n3734-97-2 Amiton Oxalate 100 100/10,000\n3735-23-7 Methyl Phenkapton 500 500\n3878-19-1 Fuberidazole 100 100/10,000\n4044-65-9 Bitoscanate 500 500/10,000\n4098-71-9 Isophorone Diisocyanate g 500 500\n4104-14-7 Phosacetim 100 100/10,000\n4170-30-3 Crotonaldehyde 100 1,000\n4301-50-2 Fluenetil 100 100/10,000\n4418-66-0 Phenol, 2,2′-Thiobis(4-Chloro-6-Methyl)- 100 100/10,000\n4835-11-4 Hexamethylenediamine, N,N′-Dibutyl- 500 500\n5344-82-1 Thiourea, (2-Chlorophenyl)- 100 100/10,000\n5836-29-3 Coumatetralyl 500 500/10,000\n6533-73-9 Thallous Carbonate b, d 100 100/10,000\n6923-22-4 Monocrotophos 10 10/10,000\n7446-09-5 Sulfur Dioxide f 500 500\n7446-11-9 Sulfur Trioxide a 100 100\n7446-18-6 Thallous Sulfate 100 100/10,000\n7487-94-7 Mercuric Chloride 500 500/10,000\n7550-45-0 Titanium Tetrachloride 1,000 100\n7580-67-8 Lithium Hydride a 100 100\n7631-89-2 Sodium Arsenate 1 1,000/10,000\n7637-07-2 Boron Trifluoride 500 500\n7647-01-0 Hydrogen Chloride (gas only) f 5,000 500\n7664-39-3 Hydrogen Fluoride 100 100\n7664-41-7 Ammonia f 100 500\n7664-93-9 Sulfuric Acid 1,000 1,000\n7697-37-2 Nitric Acid 1,000 1,000\n7719-12-2 Phosphorus Trichloride 1,000 1,000\n7722-84-1 Hydrogen Peroxide (Conc \u003e52%) f 1,000 1,000\n7723-14-0 Phosphorus a, d 1 100\n7726-95-6 Bromine f 500 500\n7778-44-1 Calcium Arsenate 1 500/10,000\n7782-41-4 Fluorine e 10 500\n7782-50-5 Chlorine 10 100\n7783-00-8 Selenious Acid 10 1,000/10,000\n7783-06-4 Hydrogen Sulfide f 100 500\n7783-07-5 Hydrogen Selenide 10 10\n7783-60-0 Sulfur Tetrafluoride 100 100\n7783-70-2 Antimony Pentafluoride 500 500\n7783-80-4 Tellurium Hexafluoride e 100 100\n7784-34-1 Arsenous Trichloride 1 500\n7784-42-1 Arsine 100 100\n7784-46-5 Sodium Arsenite 1 500/10,000\n7786-34-7 Mevinphos 10 500\n7791-12-0 Thallous Chloride b, d 100 100/10,000\n7791-23-3 Selenium Oxychloride 500 500\n7803-51-2 Phosphine 100 500\n8001-35-2 Camphechlor 1 500/10,000\n8065-48-3 Demeton 500 500\n10025-73-7 Chromic Chloride 1 1/10,000\n10025-87-3 Phosphorus Oxychloride 1,000 500\n10026-13-8 Phosphorus Pentachloride a 500 500\n10028-15-6 Ozone 100 100\n10031-59-1 Thallium Sulfate d 100 100/10,000\n10102-18-8 Sodium Selenite d 100 100/10,000\n10102-20-2 Sodium Tellurite 500 500/10,000\n10102-43-9 Nitric Oxide b 10 100\n10102-44-0 Nitrogen Dioxide 10 100\n10124-50-2 Potassium Arsenite 1 500/10,000\n10140-87-1 Ethanol, 1,2-Dichloro-, Acetate 1,000 1,000\n10210-68-1 Cobalt Carbonyl d 10 10/10,000\n10265-92-6 Methamidophos 100 100/10,000\n10294-34-5 Boron Trichloride 500 500\n10311-84-9 Dialifor 100 100/10,000\n10476-95-6 Methacrolein Diacetate 1,000 1,000\n12002-03-8 Paris Green 1 500/10,000\n12108-13-3 Manganese, Tricarbonyl Methylcyclopentadienyl d 100 100\n13071-79-9 Terbufosh d 100 100\n13171-21-6 Phosphamidon 100 100\n13194-48-4 Ethoprophos 1,000 1,000\n13410-01-0 Sodium Selenate 100 100/10,000\n13450-90-3 Gallium Trichloride 500 500/10,000\n13463-39-3 Nickel Carbonyl 10 1\n13463-40-6 Iron, Pentacarbonyl- 100 100\n14167-18-1 Salcomine 500 500/10,000\n15271-41-7 Bicyclo[2.2.1]Heptane-2-Carbonitrile, 5-Chloro-6-((((Methylamino)Carbonyl)Oxy)Imino)-, (1s-(1-alpha,2-beta,4-alpha,5-alpha,6E))- 500 500/10,000\n16752-77-5 Methomyl d 100 500/10,000\n17702-41-9 Decaborane(14) 500 500/10,000\n17702-57-7 Formparanate 100 100/10,000\n19287-45-7 Diborane 100 100\n19624-22-7 Pentaborane 500 500\n20830-75-5 Digoxin d 10 10/10,000\n20859-73-8 Aluminum Phosphide a 100 500\n21548-32-3 Fosthietan 500 500\n21609-90-5 Leptophos 500 500/10,000\n21908-53-2 Mercuric Oxide 500 500/10,000\n21923-23-9 Chlorthiophos d 500 500\n22224-92-6 Fenamiphos 10 10/10,000\n23135-22-0 Oxamyl 100 100/10,000\n23422-53-9 Formetanate Hydrochloride d 100 500/10,000\n23505-41-1 Pirimifos-Ethyl 1,000 1,000\n24017-47-8 Triazofos 500 500\n24934-91-6 Chlormephos 500 500\n26419-73-8 Carbamic Acid, Methyl-, O-(((2,4-Dimethyl-1, 3-Dithiolan-2-yl)Methylene)Amino)- 100 100/10,000\n26628-22-8 Sodium Azide (Na(N3)) a 1,000 500\n27137-85-5 Trichloro(Dichlorophenyl)Silane 500 500\n28347-13-9 Xylylene Dichloride 100 100/10,000\n28772-56-7 Bromadiolone 100 100/10,000\n30674-80-7 Methacryloyloxyethyl Isocyanateh 100 100\n39196-18-4 Thiofanox 100 100/10,000\n50782-69-9 Phosphonothioic Acid, Methyl-, S-(2-(Bis(1-Methylethyl)Amino)Ethyl) O-Ethyl Ester 100 100\n53558-25-1 Pyriminil d 100 100/10,000\n58270-08-9 Zinc, Dichloro(4,4-Dimethyl-5((((Methylamino) Carbonyl)Oxy)Imino)Pentanenitrile)-, (T-4)- 100 100/10,000\n62207-76-5 Cobalt, ((2,2′-(1,2-Ethanediylbis (Nitrilomethylidyne)) Bis(6-Fluorophenolato)) (2-)-N,N′,O,O′)- 100 100/10,000\n* Only the statutory or final RQ is shown. For more information, see 40 CFR 355.61.\nNotes:\na. This material is a reactive solid. The TPQ does not default to 10,000 pounds for non-powder, non-molten, non-solution form.\nb. The calculated TPQ changed after technical review as described in a technical support document for the final rule, April 22, 1987.\nc. Chemicals added by final rule, April 22, 1987.\nd. Revised TPQ based on new or re-evaluated toxicity data, April 22, 1987.\ne. The TPQ was revised due to calculation error, April 22, 1987.\nf. Chemicals on the original list that do not meet toxicity criteria but because of their acute lethality, high production volume and known risk are considered chemicals of concern (“Other chemicals”). (November 17, 1986, and February 15, 1990.)\ng. The TPQ was recalculated (September 8, 2003) since it was mistakenly calculated in the April 22, 1987, final rule under the wrong assumption that this chemical is a reactive solid, when in fact it is a liquid. RQ for this chemical was adjusted on September 11, 2006.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER J—SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS","PART 355—EMERGENCY PLANNING AND NOTIFICATION"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"11749efd94c7da6d6a46b3d27bfbcf8d9f45d835cb1ff113ce8820eb7f8cd1fa","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-appendix-a-to-part-355","next":"us/40-cfr-370.1"},"notice":"GroundRules: Original legal text. Not legal advice."}