Firewall (structure)

A firewall was a physical barrier that protected against fire.

While studying the plasma geyser on Melnos IV, Nella Daren and a team of geologists used interconnected thermal deflector units to protect themselves from the heat. When she recalled the measure in 2367, Geordi La Forge referred to their makeshift device as a firewall. (TNG: "Lessons")

Metaphorically, the term firewall could refer to regulatory safeguards put in place to prevent a potentially dangerous outcome. In 2373, Rear admiral Bennett explained the harsh 10 year sentence Richard Bashir had been given for seeking genetic enhancement for his son, Julian Bashir, saying, "The law against genetic engineering provides a firewall against such men (i.e. despotic Augments like Khan Noonien Singh) and it's my job to keep that firewall intact." (DS9: "Doctor Bashir, I Presume")

External link