In Captain Phasma #1 (via io9), we see the metallic-armored trooper breaking free thanks to the Resistance’s attack blowing hole in the compactor.
When we left off with Phasma in The Force Awakens, Finn, her former subordinate, had joyfully suggested to Han Solo and Chewbacca that they stuff her into a garbage compactor.
From there, Phasma rushes to a computer so she can wipe the record that her security codes were used to shut off Starkiller Base’s shields.
That would be humiliating for anyone, but Phasma was able to make sure it didn’t end up being a death sentence.