Why do many secondary explosives require a detonator or booster?

Secondary explosives are categorized as high explosives that are relatively insensitive to stimuli such as heat, friction, or impact, which makes them safer to handle, store, and transport compared to primary explosives. Because they are stable, they cannot be reliably initiated by simple ignition sources like a flame or a spark.12

To trigger their rapid decomposition, secondary explosives require a detonator, which provides a powerful shock wave to initiate the reaction. In many applications, a supplementary booster is also used to bridge the gap between the small output of a detonator and the larger, more insensitive main charge, ensuring the entire explosive mass detonates effectively. This multi-stage initiation process is essential for maintaining safety while ensuring the material can still deliver its intended shattering power when needed.132