Three Hazard Classification Class A includes compounds that form dangerous explosive peroxides without concentration. These include diisoproply ether, divinylacetylene, vinylidene chloride, potassium metal, and sodium amide. Class B includes compounds that form peroxides but are only dangerous when concentrated by evaporation or distillation. Examples are diethyl ether, dioxane, THF, tetralin, and cyclohexene. Class C includes monomers in which peroxide formation may initiate explosive polymerization.
Examples are styrene, butadiene, and vinyl monomers.