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Hazard Class 4: Flammable Solids


Solid materials that pose a serious risk of fire in uncontrolled conditions.  The hazard class is divided into three broad categories.

Subsets of class 4 are:

  • 4.1 Flammable Solids are readily combustible, or may contribute to a fire through friction.These include:
    • Flammable solids
    • Self reactive substances
    • Solid desensitized explosives
  • 4.2 Spontaneously Combustible materials (also called substances liable to spontaneous combustion) are liable to spontaneous generation of heat during transportation which can then lead to a fire. These include:
    • Pyrophoric substances
    • Self-heating substances
  • 4.3 Water Reactive (also called dangerous when wet) substances emit a flammable gas when in contact with water.

Shipping Options

  • Become Trained - All shipments of Class 4 material require the shipper to be trained and certified.  EHS certifies all shippers at Cornell. All training whether on site or by an outside vendor EHS must review training and issue a certificate of training.

  • Contact EHS - EHS has employees trained in the shipping of hazardous material and can ship your material for you (EHS 607-255-8200).