There are 6 GRE Quarantine Buildings in Dying Light 2. You may find a total of 24 inhibitors stored there. Collecting all these inhibitors unlocks the "Can't You Read the Signs?" achievement / trophy.
GRE Quarantines are night activities and all of them have a similar layout. You start at the roof of the quarantine building and then you head downstairs floor by floor. Inside each building you will find 3 crates containing Inhibitors. The first and second crate contain 1 Inhibitor each, and the last crate always contains 2 Inhibitors.
When the THV pandemic hit Europe, Villedor was among 20 cities that became testbeds for finding a cure for the virus. As part of the 'Protocol', the GRE created ad-hoc Research Centers, forcibly relocating the tenants of city-owned buildings. It is believed that they still contain GRE research (and dirty secrets)... including Inhibitors.
