UN CLASS 1.
EXPLOSIVE A: Items are capable of exploding with a small spark, shock, or flame and spreading the explosion hazard to other packages.
EXPLOSIVE B: Items are very rapidly combustible.
EXPLOSIVE C: Items are a low hazard but may explode under high heat when many are tightly packed together.
Examples: A–dynamite; B–propellants or flares; C–common fireworks.
Hazards/precautions: no flares, smoking, flames, or sparks in the hazard area; may explode if dropped, heated or sparked.