Appendix C: Peroxide Forming Chemicals Management
Class A - Severe Peroxide Hazard
Spontaneously decompose and become explosive with exposure to air without concentration. Test for peroxide formation before using or discard 3 months after opening or at the expiration date on the container if unopened. If a container of a Class A peroxide is past its expiration date, or if the presence of peroxides is suspected or proven, do not attempt to open the container.
| Chemical Name | CAS Number |
| Butadiene (liquid monomer) | 106-99-0 |
| Chloroprene (liquid monomer) | 126-99-8 |
| Divinyl ether | 109-93-3 |
| Isopropyl ether | 108-20-3 |
| Potassium amide | 17242-52-3 |
| Potassium metal | 7440-09-7 |
| Sodium amide (sodamide) | 7782-92-5 |
| Tetrafluoroethylene (liquid monomer) | 116-14-3 |
| Vinylidene chloride | 75-35-4 |
Class B - Concentration Hazard
Require external energy for spontaneous decomposition. Form explosive peroxides when distilled, evaporated or otherwise concentrated. Test these for peroxide formation before distillation or evaporation. Maintain a testing program/schedule to test for peroxide formation or discard 1 year after opening or at the expiration date on the container if unopened.
| Chemical Name | CAS Number |
| Acetal | 105-57-7 |
| Acetaldehyde | 75-07-0 |
| Benzyl alcohol | 100-51-6 |
| 2-Butanol | 78-92-2 |
| Cumene | 98-82-8 |
| Cyclohexanol | 108-93-0 |
| 2-Cyclohexen-1-ol | 822-67-3 |
| Cyclohexene | 110-83-8 |
| Decahydronaphthalene (decalin) | 91-17-8 |
| Diacetylene (butadine, gas) | 460-12-8 |
| Dicyclopentadiene | 77-73-6 |
| Diethyl ether (ether) | 60-29-7 |
| Diethylene glycol dimethyl ether (diglyme) | 111-96-6 |
| Dioxanes | N/A |
| Ethylene glycol ether acetates (glyme) | 110-71-4 |
| Furan | 110-00-9 |
| 4-Heptanol | 589-55-9 |
| 2-Hexanol | 626-93-7 |
| Methyl cyclopentane | 96-37-7 |
| Methyl isobutyl ketone | 108-10-1 |
| 3-Methyl-1-butanol | 123-51-3 |
| 4-Methyl-2-pentanol | 108-11-2 |
| Methylacetylene (gas) | 74-99-7 |
| Other secondary alcohols | N/A |
| 2-Pentanol | 6032-29-7 |
| 4-Penten-1-ol | 821-09-0 |
| 1-Phenylethanol | 98-85-1 |
| 2-Phenylethanol | 60-12-8 |
| Tetrahydrofuran (THF) | 109-99-9 |
| Tetrahydronaphthalene (tetralin) | 119-64-2 |
| Vinyl ethers | N/A |
Class C - Shock and Heat Sensitive
Highly reactive and can auto-polymerize as a result of internal peroxide accumulation. The peroxides formed in these reactions are extremely shock- and heat-sensitive. Materials should be disposed of 1 year after opening or at the expiration date on the container if unopened.
| Chemical Name | CAS Number |
| Acrylic acid | 79-10-7 |
| Acrylonitrile | 107-13-1 |
| Butadiene (gas) | 106-99-0 |
| Chlorobutadiene | 126-99-8 |
| Chloroprene | 126-99-8 |
| Chlorotrifluoroethylene (gas) | 79-38-9 |
| Methyl methacrylate | 80-62-6 |
| Styrene | 100-42-5 |
| Tetrafluoroethylene (gas) | 116-14-3 |
| Vinyl acetate | 108-05-4 |
| Vinyl chloride (gas) | 75-01-4 |
| Vinyl pyridine | 100-69-6; 100-43-6 |
| Vinylacetylene (gas) | 689-97-4 |
| Vinyldiene chloride | 75-35-4 |
Class D
Materials that do not fit within Group A or B, but require special handling.
| Chemical Name | CAS Number |
| Acrolein | 107-02-8 |
| Allyl ether | 557-40-4 |
| Allyl ethyl ether | 557-31-3 |
| Allyl phenyl ether | 1746-13-0 |
| n-Amyl ether | 693-65-2 |
| p-(n-Amyloxy)benzoyl chloride | 36823-84-4 |
| Benzyl ether | 103-50-4 |
| Benzyl ethyl ether | 539-30-0 |
| Benzyl methyl ether | 538-86-3 |
| Benzyl n-butyl ether | 588-67-0; 3459-80-1 |
| Benzyl-1-napthyl ether | 607-58-9 |
| Bis(2-(methoxyethoxy)ethyl) ether | 143-24-8 |
| 1,2-Bis(2-chloroethoxyl)ethane | 112-26-5 |
| Bis(2-chloroethyl) ether | 111-44-4 |
| Bis(2-ethoxyethyl) adipate | 109-44-4 |
| Bis(2-ethoxyethyl)ether | 112-36-7 |
| Bis(2-methoxyethyl) carbonate | 626-84-6 |
| Bis(2-methoxyethyl) ether | 111-96-6 |
| Bis(2-methoxyethyl) phthalate | 117-82-8 |
| Bis(2-methoxymethyl) adipate | 109-44-4 |
| Bis(2-n-butoxyethyl) phthalate | 117-83-9 |
| Bis(2-phenoxyethyl) ether | 622-87-7 |
| Bis(4-chlorobutyl) ether | 6334-96-9 |
| Bis(chloromethyl) ether | 542-88-1 |
| 2-Bromomethyl ethyl ether | 592-55-2 |
| beta-Bromophenetole | 589-10-6 |
| o-Bromophenetole | 583-19-7 |
| p-Bromophenetole | 588-96-5 |
| 3-Bromopropyl phenyl ether | 588-63-6 |
| tert-Butyl methyl ether | 1634-04-4 |
| n-Butyl phenyl ether | 1126-79-0 |
| n-Butyl vinyl ether | 111-34-2 |
| Chloroacetaldehyde diethylacetal | 107-20-0; 107-30-2 |
| 2-Chlorobutadiene | 126-99-8 |
| 1-(2-Chloroethoxy)-2-phenoxyethane | 2243-44-9 |
| Chloroethylene | 75-01-4 |
| Chloromethyl methyl ether | 107-30-2 |
| beta-Chlorophenetole | 622-86-6 |
| o-Chlorophenetole | 143-24-8 |
| p-Chlorophenetole | 622-61-7 |
| Cyclooctene | 931-88-4; 931-87-3 |
| Cyclopropyl methyl ether | 540-47-6 |
| p-Di-n-butoxybenzene | 75942-37-9 |
| Di-n-propoxymethane | 505-84-0 |
| Dipropyl ether | 111-43-3 |
| Di(2-propynl) ether | |
| Diallyl ether | 557-40-4 |
| p-Dibenzyloxybenzene | 621-91-0 |
| 1,2-Dibenzyloxyethane | 622-22-0 |
| 1,2-Dichloroethyl ethyl ether | 623-46-1 |
| 2,4-Dichlorophenetole | 5392-86-9 |
| Diethoxybenzene (m-,o-,p-) | 2168-54-9 |
| 1,2-Diethoxyethane | 629-14-1 |
| Diethoxymethane | 462-95-3 |
| 2,2-Diethoxypropane | 126-84-1 |
| Diethyl acetal | 105-57-7 |
| Diethyl ethoxymethylenemalonate | 87-13-8 |
| Diethyl fumarate | 623-91-6 |
| Diethylketene | 96-22-0 |
| 1,1-Dimethoxyethane | 534-15-6 |
| Dimethoxymethane | 109-87-5 |
| 1,2-Epoxy-3-isopropoxypropane | 4016-14-2 |
| 1,2-Epoxy-3-phenoxypropane | 122-60-1 |
| 1-Ethoxy-2-propyne | |
| p-Ethoxyacetophenone | 1676-63-7 |
| 2-(2-Ethoxyethoxy)ethyl acetate | 112-15-2 |
| 2-Ethoxyethyl acetate | 111-15-9 |
| (2-Ethoxyethyl)-a-benzoyl benzoate | 604-63-7 |
| 1-Ethoxynaphthalene | 5328-01-8; 75440-80-1 |
| o,p-Ethoxyphenyl isocyanate | 5395-71-1 |
| 3-Ethoxypropionitrile | 2141-62-0 |
| Ethyl vinyl ether | 109-92-2 |
| Ethyl-b-ethoxypropionate | 763-69-9 |
| 2-Ethylacrylaldehyde oxime | 99705-27-8 |
| 2-Ethylbutanol | 97-95-0 |
| Ethylene glycol monomethyl ether | 109-86-4 |
| 2-Ethylhexanal | 123-05-7 |
| 4,5-Hexadien-2-yn-1-ol | 2749-79-3 |
| 2,5-Hexadiyn-1-ol | 28255-99-4 |
| n-Hexyl ether | 112-58-3 |
| p-Iodophenetole | 699-08-1 |
| Isoamyl benzyl ether | 122-73-6 |
| Isoamyl ether | 544-01-4 |
| Isobutyl vinyl ether | 109-53-5 |
| Isophorone | 78-59-1 |
| b-Isopropoxypropionitrile | 110-47-4 |
| Isopropyl-2,4,5-trichlorophenoxy acetate | 93-78-7 |
| 3-Methoxy-1-butyl acetate | 4435-53-4 |
| Methoxy-1,3,5,7-cyclooctatetraene | 7176-89-8 |
| 2-Methoxyethanol | 32718-54-0; 109-86-4 |
| 2-Methoxyethyl acetate | 110-49-6 |
| 2-Methoxyethyl vinyl ether | 1663-35-0 |
| b-Methoxypropionitrile | 110-67-8 |
| m-Methylphenetole | 621-32-9 |
| 2-Methyltetrahydrofuran | 96-47-9 |
| m-Nitrophenetole | 621-52-3 |
| 1-Octene | 173994-67-7; 25377-83-7; 111-66-0 |
| Oxybis(2-ethyl acetate) | 628-68-2 |
| Oxybis(2-ethyl benzoate) | 56-35-9 |
| b,b-Oxydipropionitrile | 1656-48-0 |
| 1-Pentene | 25377-72-4; 109-67-1 |
| Phenoxyacetyl chloride | 701-99-5 |
| a-Phenoxypropionyl chloride | 122-35-0 |
| Phenyl Propyl Ether | 622-85-5 |
| p-Phenylphenetone | |
| n-Propyl ether | 111-43-3 |
| n-Propyl isopropyl ether | 627-08-7 |
| Sodium arachidonate | 6610-25-9 |
| Sodium ethoxyacetylide | 73506-39-5 |
| 1,1,2,3-Tetrachloro-1,3-butadiene | 921-09-5 |
| Tetrahydropyran | 142-68-7 |
| Triethylene glycol diacetate | 111-21-7 |
| Triethylene glycol dipropionate | 141-34-4 |
| 1,3,3-Trimethoxypropene | 17576-35-1 |
| 4-Vinyl cyclohexene | 100-40-3 |
| Vinylene carbonate | 872-36-6 |
References:
- Clark D. E., “ Peroxides and Peroxide-Forming Compounds”, J. or Chem. Health and Safety, 2001 8(5), 12-18.
- Kelly, R. J., “ Review of Safety Guidelines for Peroxidizable Organic Chemicals”, Chem. Health & Safety, 1996, 3(5), 28–36.
- National Research Council, Prudent Practices in the Laboratory, National Academy Press: Washington, DC, 2011
Acknowledgement:
KSU Environmental Health and Safety acknowledges the assistance of the UC Santa Cruz Office of Environmental Health & Safety, whose webpage (https://ehs.ucsc.edu/lab-safety-manual/index.html) has served as useful resources.