Division 4.1: Flammable Solids, Self-Reactive Substances, and Solid Desensitized Explosives

Materials in this division consist of:

  • Desensitized Explosives—Wetted with sufficient water, alcohol, or plasticizers to suppress explosive properties
  • Self-Reactive Materials—Thermally unstable and can undergo a strongly exothermic decomposition even with participation of oxygen
  • Readily Combustible Solids—Solids that cause a fire from friction and any metal powders that can be ignited

Examples include red phosphorus, sulphur, and nitrocellulose.

Image of a brown cardboard box filled with red cylindrical tubes, with a red white and blue box of kitchen matches sitting on top of them. On the outside of the cardboard box is a diamond placard with alternating vertical stripes of red and white and the words flammable solid written in black in the middle underneath a black flame.