{"data":{"id":"us/40-cfr-appendix-a-to-part-355","jurisdiction":"us","citation":"40 CFR Appendix A to Part 355","heading":"Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities","body":"[Alphabetical Order]\nCAS No. Chemical name Notes Reportable quantity * (pounds) Threshold planning quantity (pounds)\n75-86-5 Acetone Cyanohydrin 10 1,000\n1752-30-3 Acetone Thiosemicarbazide 1,000 1,000/10,000\n107-02-8 Acrolein 1 500\n79-06-1 Acrylamide f 5,000 1,000/10,000\n107-13-1 Acrylonitrile f 100 10,000\n814-68-6 Acrylyl Chloride d 100 100\n111-69-3 Adiponitrile f 1,000 1,000\n116-06-3 Aldicarb b 1 100/10,000\n309-00-2 Aldrin 1 500/10,000\n107-18-6 Allyl Alcohol 100 1,000\n107-11-9 Allylamine 500 500\n20859-73-8 Aluminum Phosphide a 100 500\n54-62-6 Aminopterin 500 500/10,000\n78-53-5 Amiton 500 500\n3734-97-2 Amiton Oxalate 100 100/10,000\n7664-41-7 Ammonia f 100 500\n300-62-9 Amphetamine 1,000 1,000\n62-53-3 Aniline f 5,000 1,000\n88-05-1 Aniline, 2,4,6-Trimethyl- 500 500\n7783-70-2 Antimony Pentafluoride 500 500\n1397-94-0 Antimycin A b 1,000 1,000/10,000\n86-88-4 ANTU 100 500/10,000\n1303-28-2 Arsenic Pentoxide 1 100/10,000\n1327-53-3 Arsenous Oxide d 1 100/10,000\n7784-34-1 Arsenous Trichloride 1 500\n7784-42-1 Arsine 100 100\n2642-71-9 Azinphos-Ethyl 100 100/10,000\n86-50-0 Azinphos-Methyl 1 10/10,000\n98-87-3 Benzal Chloride 5,000 500\n98-16-8 Benzenamine, 3-(Trifluoromethyl)- 500 500\n100-14-1 Benzene, 1-(Chloromethyl)-4-Nitro- 500 500/10,000\n98-05-5 Benzenearsonic Acid 10 10/10,000\n3615-21-2 Benzimidazole, 4,5-Dichloro-2-(Trifluoromethyl)- c 500 500/10,000\n98-07-7 Benzotrichloride 10 100\n100-44-7 Benzyl Chloride 100 500\n140-29-4 Benzyl Cyanide d 500 500\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\n534-07-6 Bis(Chloromethyl) Ketone 10 10/10,000\n4044-65-9 Bitoscanate 500 500/10,000\n10294-34-5 Boron Trichloride 500 500\n7637-07-2 Boron Trifluoride 500 500\n353-42-4 Boron Trifluoride Compound With Methyl Ether (1:1) 1,000 1,000\n28772-56-7 Bromadiolone 100 100/10,000\n7726-95-6 Bromine f 500 500\n1306-19-0 Cadmium Oxide 100 100/10,000\n2223-93-0 Cadmium Stearate b 1,000 1,000/10,000\n7778-44-1 Calcium Arsenate 1 500/10,000\n8001-35-2 Camphechlor 1 500/10,000\n56-25-7 Cantharidin 100 100/10,000\n51-83-2 Carbachol Chloride 500 500/10,000\n26419-73-8 Carbamic Acid, Methyl-, O-(((2,4-Dimethyl-1, 3-Dithiolan-2-yl)Methylene)Amino)- 100 100/10,000\n1563-66-2 Carbofuran 10 10/10,000\n75-15-0 Carbon Disulfide f 100 10,000\n786-19-6 Carbophenothion 500 500\n57-74-9 Chlordane 1 1,000\n470-90-6 Chlorfenvinfos 500 500\n7782-50-5 Chlorine 10 100\n24934-91-6 Chlormephos 500 500\n999-81-5 Chlormequat Chloride d 100 100/10,000\n79-11-8 Chloroacetic Acid 100 100/10,000\n107-07-3 Chloroethanol 500 500\n627-11-2 Chloroethyl Chloroformate 1,000 1,000\n67-66-3 Chloroform f 10 10,000\n542-88-1 Chloromethyl Ether d 10 100\n107-30-2 Chloromethyl Methyl Ether b 10 100\n3691-35-8 Chlorophacinone 100 100/10,000\n1982-47-4 Chloroxuron 500 500/10,000\n21923-23-9 Chlorthiophos d 500 500\n10025-73-7 Chromic Chloride 1 1/10,000\n62207-76-5 Cobalt, ((2,2′-(1,2-Ethanediylbis (Nitrilomethylidyne)) Bis(6-Fluorophenolato))(2-)-N,N′,O,O′)- 100 100/10,000\n10210-68-1 Cobalt Carbonyl d 10 10/10,000\n64-86-8 Colchicine d 10 10/10,000\n56-72-4 Coumaphos 10 100/10,000\n5836-29-3 Coumatetralyl 500 500/10,000\n95-48-7 Cresol, o- 100 1,000/10,000\n535-89-7 Crimidine 100 100/10,000\n4170-30-3 Crotonaldehyde 100 1,000\n123-73-9 Crotonaldehyde, (E)- 100 1,000\n506-68-3 Cyanogen Bromide 1,000 500/10,000\n506-78-5 Cyanogen Iodide 1,000 1,000/10,000\n2636-26-2 Cyanophos 1,000 1,000\n675-14-9 Cyanuric Fluoride 100 100\n66-81-9 Cycloheximide 100 100/10,000\n108-91-8 Cyclohexylamine f 10,000 10,000\n17702-41-9 Decaborane(14) 500 500/10,000\n8065-48-3 Demeton 500 500\n919-86-8 Demeton-S-Methyl 500 500\n10311-84-9 Dialifor 100 100/10,000\n19287-45-7 Diborane 100 100\n111-44-4 Dichloroethyl ether 10 10,000\n149-74-6 Dichloromethylphenylsilane 1,000 1,000\n62-73-7 Dichlorvos 10 1,000\n141-66-2 Dicrotophos 100 100\n1464-53-5 Diepoxybutane 10 500\n814-49-3 Diethyl Chlorophosphate d 500 500\n71-63-6 Digitoxin b 100 100/10,000\n2238-07-5 Diglycidyl Ether 1,000 1,000\n20830-75-5 Digoxin d 10 10/10,000\n115-26-4 Dimefox 500 500\n60-51-5 Dimethoate 10 500/10,000\n2524-03-0 Dimethyl Phosphorochloridothioate 500 500\n77-78-1 Dimethyl sulfate 100 500\n75-78-5 Dimethyldichlorosilane d 500 500\n57-14-7 Dimethylhydrazine 10 1,000\n99-98-9 Dimethyl-p-Phenylenediamine 10 10/10,000\n644-64-4 Dimetilan 1 500/10,000\n534-52-1 Dinitrocresol 10 10/10,000\n88-85-7 Dinoseb 1,000 100/10,000\n1420-07-1 Dinoterb 500 500/10,000\n78-34-2 Dioxathion 500 500\n82-66-6 Diphacinone 10 10/10,000\n152-16-9 Diphosphoramide, Octamethyl- 100 100\n298-04-4 Disulfoton 1 500\n514-73-8 Dithiazanine Iodide 500 500/10,000\n541-53-7 Dithiobiuret 100 100/10,000\n316-42-7 Emetine, Dihydrochloride d 1 1/10,000\n115-29-7 Endosulfan 1 10/10,000\n2778-04-3 Endothion 500 500/10,000\n72-20-8 Endrin 1 500/10,000\n106-89-8 Epichlorohydrin f 100 1,000\n2104-64-5 EPN 100 100/10,000\n50-14-6 Ergocalciferol b 1,000 1,000/10,000\n379-79-3 Ergotamine Tartrate 500 500/10,000\n1622-32-8 Ethanesulfonyl Chloride, 2-Chloro- 500 500\n10140-87-1 Ethanol, 1,2-Dichloro-, Acetate 1,000 1,000\n563-12-2 Ethion 10 1,000\n13194-48-4 Ethoprophos 1,000 1,000\n538-07-8 Ethylbis(2-Chloroethyl)Amine d 500 500\n371-62-0 Ethylene Fluorohydrin b, d 10 10\n75-21-8 Ethylene Oxide f 10 1,000\n107-15-3 Ethylenediamine 5,000 10,000\n151-56-4 Ethyleneimine 1 500\n542-90-5 Ethylthiocyanate 10,000 10,000\n22224-92-6 Fenamiphos 10 10/10,000\n115-90-2 Fensulfothion d 500 500\n4301-50-2 Fluenetil 100 100/10,000\n7782-41-4 Fluorine e 10 500\n640-19-7 Fluoroacetamide 100 100/10,000\n144-49-0 Fluoroacetic Acid 10 10/10,000\n359-06-8 Fluoroacetyl Chloride b 10 10\n51-21-8 Fluorouracil 500 500/10,000\n944-22-9 Fonofos 500 500\n50-00-0 Formaldehyde f 100 500\n107-16-4 Formaldehyde Cyanohydrin d 1,000 1,000\n23422-53-9 Formetanate Hydrochloride d 100 500/10,000\n2540-82-1 Formothion 100 100\n17702-57-7 Formparanate 100 100/10,000\n21548-32-3 Fosthietan 500 500\n3878-19-1 Fuberidazole 100 100/10,000\n110-00-9 Furan 100 500\n13450-90-3 Gallium Trichloride 500 500/10,000\n77-47-4 Hexachlorocyclopentadiene d 10 100\n4835-11-4 Hexamethylenediamine, N,N′-Dibutyl- 500 500\n302-01-2 Hydrazine 1 1,000\n74-90-8 Hydrocyanic Acid 10 100\n7647-01-0 Hydrogen Chloride (gas only) f 5,000 500\n7664-39-3 Hydrogen Fluoride 100 100\n7722-84-1 Hydrogen Peroxide (Conc \u003e52%) f 1,000 1,000\n7783-07-5 Hydrogen Selenide 10 10\n7783-06-4 Hydrogen Sulfide f 100 500\n123-31-9 Hydroquinone f 100 500/10,000\n13463-40-6 Iron, Pentacarbonyl- 100 100\n297-78-9 Isobenzan 100 100/10,000\n78-82-0 Isobutyronitrile d 1,000 1,000\n102-36-3 Isocyanic Acid, 3,4-Dichlorophenyl Ester 500 500/10,000\n465-73-6 Isodrin 1 100/10,000\n55-91-4 Isofluorphate b 100 100\n4098-71-9 Isophorone Diisocyanate g 500 500\n108-23-6 Isopropyl Chloroformate 1,000 1,000\n119-38-0 Isopropylmethyl-pyrazolyl Dimethylcarbamate 100 500\n78-97-7 Lactonitrile 1,000 1,000\n21609-90-5 Leptophos 500 500/10,000\n541-25-3 Lewisite b, d 10 10\n58-89-9 Lindane 1 1,000/10,000\n7580-67-8 Lithium Hydride a 100 100\n109-77-3 Malononitrile 1,000 500/10,000\n12108-13-3 Manganese, Tricarbonyl Methylcyclopentadienyl d 100 100\n51-75-2 Mechlorethamine b 10 10\n950-10-7 Mephosfolan 500 500\n1600-27-7 Mercuric Acetate 500 500/10,000\n7487-94-7 Mercuric Chloride 500 500/10,000\n21908-53-2 Mercuric Oxide 500 500/10,000\n10476-95-6 Methacrolein Diacetate 1,000 1,000\n760-93-0 Methacrylic Anhydride 500 500\n126-98-7 Methacrylonitrile d 1,000 500\n920-46-7 Methacryloyl Chloride 100 100\n30674-80-7 Methacryloyloxyethyl Isocyanate d 100 100\n10265-92-6 Methamidophos 100 100/10,000\n558-25-8 Methanesulfonyl Fluoride 1,000 1,000\n950-37-8 Methidathion 500 500/10,000\n2032-65-7 Methiocarb 10 500/10,000\n16752-77-5 Methomyl d 100 500/10,000\n151-38-2 Methoxyethylmercuric Acetate 500 500/10,000\n80-63-7 Methyl 2-Chloroacrylate 500 500\n74-83-9 Methyl Bromide f 1,000 1,000\n79-22-1 Methyl Chloroformate d 1,000 500\n60-34-4 Methyl Hydrazine 10 500\n624-83-9 Methyl Isocyanate 10 500\n556-61-6 Methyl Isothiocyanate a 500 500\n74-93-1 Methyl Mercaptan f 100 500\n3735-23-7 Methyl Phenkapton 500 500\n676-97-1 Methyl Phosphonic Dichloride a 100 100\n556-64-9 Methyl Thiocyanate 10,000 10,000\n78-94-4 Methyl Vinyl Ketone 10 10\n502-39-6 Methylmercuric Dicyanamide 500 500/10,000\n75-79-6 Methyltrichlorosilane d 500 500\n1129-41-5 Metolcarb 1,000 100/10,000\n7786-34-7 Mevinphos 10 500\n315-18-4 Mexacarbate d 1,000 500/10,000\n50-07-7 Mitomycin C 10 500/10,000\n6923-22-4 Monocrotophos 10 10/10,000\n2763-96-4 Muscimol 1,000 500/10,000\n505-60-2 Mustard Gas d 500 500\n13463-39-3 Nickel Carbonyl 10 1\n54-11-5 Nicotine b 100 100\n65-30-5 Nicotine Sulfate 100 100/10,000\n7697-37-2 Nitric Acid 1,000 1,000\n10102-43-9 Nitric Oxide b 10 100\n98-95-3 Nitrobenzene f 1,000 10,000\n1122-60-7 Nitrocyclohexane 500 500\n10102-44-0 Nitrogen Dioxide 10 100\n62-75-9 Nitrosodimethylamine d 10 1,000\n991-42-4 Norbormide 100 100/10,000\nOrganorhodium Complex (PMN-82-147) 10 10/10,000\n630-60-4 Ouabain b 100 100/10,000\n23135-22-0 Oxamyl 100 100/10,000\n78-71-7 Oxetane, 3,3-Bis(Chloromethyl)- 500 500\n2497-07-6 Oxydisulfoton d 500 500\n10028-15-6 Ozone 100 100\n1910-42-5 Paraquat Dichloride 10 10/10,000\n2074-50-2 Paraquat Methosulfate 10 10/10,000\n56-38-2 Parathion b 10 100\n298-00-0 Parathion-Methyl b 100 100/10,000\n12002-03-8 Paris Green 1 500/10,000\n19624-22-7 Pentaborane 500 500\n2570-26-5 Pentadecylamine 100 100/10,000\n79-21-0 Peracetic Acid 500 500\n594-42-3 Perchloromethylmercaptan 100 500\n108-95-2 Phenol 1,000 500/10,000\n4418-66-0 Phenol, 2,2′-Thiobis(4-Chloro-6-Methyl)- 100 100/10,000\n64-00-6 Phenol, 3-(1-Methylethyl)-, Methylcarbamate 10 500/10,000\n58-36-6 Phenoxarsine, 10,10′-Oxydi- 500 500/10,000\n696-28-6 Phenyl Dichloroarsine d 1 500\n59-88-1 Phenylhydrazine Hydrochloride 1,000 1,000/10,000\n62-38-4 Phenylmercury Acetate 100 500/10,000\n2097-19-0 Phenylsilatrane d 100 100/10,000\n103-85-5 Phenylthiourea 100 100/10,000\n298-02-2 Phorate 10 10\n4104-14-7 Phosacetim 100 100/10,000\n947-02-4 Phosfolan 100 100/10,000\n75-44-5 Phosgene f 10 10\n13171-21-6 Phosphamidon 100 100\n7803-51-2 Phosphine 100 500\n2703-13-1 Phosphonothioic Acid, Methyl-, O-Ethyl O-(4-(Methylthio) Phenyl) Ester 500 500\n50782-69-9 Phosphonothioic Acid, Methyl-, S-(2-(Bis(1Methylethyl)Amino)Ethyl) O-Ethyl Ester 100 100\n2665-30-7 Phosphonothioic Acid, Methyl-, O-(4-Nitrophenyl) O-Phenyl Ester 500 500\n3254-63-5 Phosphoric Acid, Dimethyl 4-(Methylthio)Phenyl Ester 500 500\n2587-90-8 Phosphorothioic Acid, O,O-Dimethyl-S-(2-Methylthio) Ethyl Ester b, c 500 500\n7723-14-0 Phosphorus a, d 1 100\n10025-87-3 Phosphorus Oxychloride 1,000 500\n10026-13-8 Phosphorus Pentachloride a 500 500\n7719-12-2 Phosphorus Trichloride 1,000 1,000\n57-47-6 Physostigmine 100 100/10,000\n57-64-7 Physostigmine, Salicylate (1:1) 100 100/10,000\n124-87-8 Picrotoxin 500 500/10,000\n110-89-4 Piperidine 1,000 1,000\n23505-41-1 Pirimifos-Ethyl 1,000 1,000\n10124-50-2 Potassium Arsenite 1 500/10,000\n151-50-8 Potassium Cyanide a 10 100\n506-61-6 Potassium Silver Cyanide a 1 500\n2631-37-0 Promecarb d 1,000 500/10,000\n106-96-7 Propargyl Bromide 10 10\n57-57-8 Propiolactone, Beta- 10 500\n107-12-0 Propionitrile 10 500\n542-76-7 Propionitrile, 3-Chloro- 1,000 1,000\n70-69-9 Propiophenone, 4-Amino- c 100 100/10,000\n109-61-5 Propyl Chloroformate 500 500\n75-56-9 Propylene Oxide f 100 10,000\n75-55-8 Propyleneimine 1 10,000\n2275-18-5 Prothoate 100 100/10,000\n129-00-0 Pyrene b 5,000 1,000/10,000\n140-76-1 Pyridine, 2-Methyl-5-Vinyl- 500 500\n504-24-5 Pyridine, 4-Amino- d 1,000 500/10,000\n1124-33-0 Pyridine, 4-Nitro-,l-Oxide 500 500/10,000\n53558-25-1 Pyriminil d 100 100/10,000\n14167-18-1 Salcomine 500 500/10,000\n107-44-8 Sarin d 10 10\n7783-00-8 Selenious Acid 10 1,000/10,000\n7791-23-3 Selenium Oxychloride 500 500\n563-41-7 Semicarbazide Hydrochloride 1,000 1,000/10,000\n3037-72-7 Silane, (4-Aminobutyl)Diethoxymethyl- 1,000 1,000\n7631-89-2 Sodium Arsenate 1 1,000/10,000\n7784-46-5 Sodium Arsenite 1 500/10,000\n26628-22-8 Sodium Azide (Na(N3)) a 1,000 500\n124-65-2 Sodium Cacodylate 100 100/10,000\n143-33-9 Sodium Cyanide (Na(CN)) a 10 100\n62-74-8 Sodium Fluoroacetate 10 10/10,000\n13410-01-0 Sodium Selenate 100 100/10,000\n10102-18-8 Sodium Selenite d 100 100/10,000\n10102-20-2 Sodium Tellurite 500 500/10,000\n900-95-8 Stannane, Acetoxytriphenyl- c 500 500/10,000\n57-24-9 Strychnine b 10 100/10,000\n60-41-3 Strychnine Sulfate 10 100/10,000\n3689-24-5 Sulfotep 100 500\n3569-57-1 Sulfoxide, 3-Chloropropyl Octyl 500 500\n7446-09-5 Sulfur Dioxide f 500 500\n7783-60-0 Sulfur Tetrafluoride 100 100\n7446-11-9 Sulfur Trioxide a 100 100\n7664-93-9 Sulfuric Acid 1,000 1,000\n77-81-6 Tabun b, d 10 10\n7783-80-4 Tellurium Hexafluoride e 100 100\n107-49-3 TEPP 10 100\n13071-79-9 Terbufos d 100 100\n78-00-2 Tetraethyllead b 10 100\n597-64-8 Tetraethyltin b 100 100\n75-74-1 Tetramethyllead b, f 100 100\n509-14-8 Tetranitromethane 10 500\n10031-59-1 Thallium Sulfate d 100 100/10,000\n6533-73-9 Thallous Carbonate b, d 100 100/10,000\n7791-12-0 Thallous Chloride b, d 100 100/10,000\n2757-18-8 Thallous Malonate b, d 100 100/10,000\n7446-18-6 Thallous Sulfate 100 100/10,000\n2231-57-4 Thiocarbazide 1,000 1,000/10,000\n39196-18-4 Thiofanox 100 100/10,000\n297-97-2 Thionazin 100 500\n108-98-5 Thiophenol 100 500\n79-19-6 Thiosemicarbazide 100 100/10,000\n5344-82-1 Thiourea, (2-Chlorophenyl)- 100 100/10,000\n614-78-8 Thiourea, (2-Methylphenyl)- 500 500/10,000\n7550-45-0 Titanium Tetrachloride 1,000 100\n584-84-9 Toluene 2,4-Diisocyanate 100 500\n91-08-7 Toluene 2,6-Diisocyanate 100 100\n110-57-6 Trans-1,4-Dichlorobutene 500 500\n1031-47-6 Triamiphos 500 500/10,000\n24017-47-8 Triazofos 500 500\n76-02-8 Trichloroacetyl Chloride 500 500\n115-21-9 Trichloroethylsilane d 500 500\n327-98-0 Trichloronate e 500 500\n98-13-5 Trichlorophenylsilane d 500 500\n1558-25-4 Trichloro(Chloromethyl)Silane 100 100\n27137-85-5 Trichloro(Dichlorophenyl) Silane 500 500\n998-30-1 Triethoxysilane 500 500\n75-77-4 Trimethylchlorosilane 1,000 1,000\n824-11-3 Trimethylolpropane Phosphite d 100 100/10,000\n1066-45-1 Trimethyltin Chloride 500 500/10,000\n639-58-7 Triphenyltin Chloride 500 500/10,000\n555-77-1 Tris(2-Chloroethyl)Amine d 100 100\n2001-95-8 Valinomycin b 1,000 1,000/10,000\n1314-62-1 Vanadium Pentoxide 1,000 100/10,000\n108-05-4 Vinyl Acetate Monomer f 5,000 1,000\n81-81-2 Warfarin 100 500/10,000\n129-06-6 Warfarin Sodium d 100 100/10,000\n28347-13-9 Xylylene Dichloride 100 100/10,000\n58270-08-9 Zinc, Dichloro(4,4-Dimethyl-5((((Methylamino)Carbonyl) Oxy)Imino)Pentanenitrile)-, (T-4)- 100 100/10,000\n1314-84-7 Zinc Phosphide a 100 500\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":"4ff23984d534c7231cfb72d44387b3ac3adbe1a52d5a297f2bb49d5b67d81662","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-355.61","next":"us/40-cfr-appendix-b-to-part-355"},"notice":"GroundRules: Original legal text. Not legal advice."}