Quarantine was the holding of the 4400 for about 6 weeks after they returned. There was much discussion about putting the 4400 back in quarantine during both the first and second seasons. Quarantine was a dreaded experience for most of the 4400, and many remained afraid that they would be returned. The quarantine location was a series of barracks at Camp Decker. These were given the name Camp Decker Quarantine Facility.
Most of the 4400 were temporarily returned to quarantine at the end of the second season after many of them became ill because of the effects of the promicin inhibitor.
Kyle Baldwin was held in a single quarantine room ("Quarantine A" room) for about one year, from the time of the revelation on Highland Beach until his father returned to field duty at the beginning of the second season.