Plasma coolant
Plasma coolant or reactor coolant was a gaseous substance used in the operation of a starship's warp core. It was denser than air and would displace it without mixing. Plasma coolant was considered a biohazard as it liquefied organic matter on contact. ()

A coolant leak often preceded a warp core breach. (; )

In 2151, a  from  began leaking plasma coolant from a damaged thruster while landing on Archer IV. () Later that year, Lieutenant Malcolm Reed caught the common cold from opening a case of plasma coolant. () Weeks later, Enterprise supplied a thousand liters of plasma coolant to the Vahklas. ()

An Arin'Sen transport encountered by Enterprise in 2152 was venting reactor coolant from their port engine. ()

In 2153, Captain Jonathan Archer faked a reactor coolant leak during an attempt to deceive Degra. ()

The  had two plasma coolant tanks on either side of the warp core. In 2063, Lieutenant Commander Data ruptured one of the tanks to destroy the Borg Queen. ()

In 2374, one of 's coolant injectors ruptured, causing a plasma coolant leak. ()

Shortly before its destruction by the Breen, the  experienced eight EPS ruptures venting plasma coolant ()

de:Plasmakühlmittel
Warp