This is best unlocked beside this achievement:
The Shock Therapy achievement in Dead by Daylight worth 20 pointsIn a public match, repair the generator on the second floor of the Disturbed Ward and escape. This is map specific and you must be playing on the Asylum.
This is kind of an easy achievement. You can basically do nothing and escape to unlock this. Simply avoid getting hit by any of the killers attacks. Healing yourself after getting hit will not grant you the achievement.
I suggest getting this along side the other achievement as once that top generator is fixed, the killer has little reason to patrol up there so you can just camp while the rest of your "team" does the work.