Next to the matter/antimatter reaction that fuels warp plasma to the engine nacelles, the most important part of Federation warp drives is plasma coolant. When the matter-antimatter reactor combines deuterium and antideuterium within an energized dilithium crystal, the plasma generated is immensely powerful, and must be cooled by specially designed, yet hazardous, coolant compounds. Plasma coolant maintains the warp core, cooling any heat safely away from the populated areas of the starship or outpost. It operates in the same manner any coolant is used in an engine. Without it, the engine systems could overheat or fail completely. It reacts violently with organic matter, dissolving it on contact. (TNG:"Yesterday's Enterprise; Star Trek: First Contact)
- Coolant dangers aboard a starship have also been depicted in TOS:"Balance of Terror."