The on death effect is scaled by how much missile parts are stored. It will deal 3000 damage to parts in a 6 tile radius, 1500 to structure (armor) in a 4.5 tile radius, and has a 30% chance to start a fire in 6 tile radius. This can easily cause a chain reaction to occur should large amounts of missiles be stored unprotected. Armor will help stop this area damage. Meaning encasing your munition storage in armor will both protect it and other parts should it explode.