Filtration system
The filtration system was a system aboard  starships. 

In 2267, a crewman noted that the 's filtration systems were down, following an attack by the planet killer. ()

In 2370, Data compared placental barrier, maternal antibodies, and amniotic fluids to a filtration system, in that they prevented viruses like the intron virus from being passed on to developing fetuses. ()

Spacecraft sections