Several of these pods are encountered during Interval 03 - Replica in F.E.A.R. 2: Project Origin. They serve as a warning to the player that Replica soldiers might be nearby (or that they are about to appear). The Replicas come out of the pods with full-ready status, carrying weapons and wearing military uniforms and armor. Even the seemingly silent area might be populous as long as these pods are present. The pod can be multiple possible types of Replica Soldiers, including the normal ones, Heavy Troopers, Elites and even Deformed Replicas.
The Stasis pods have lights that glows green when a replica is about to come out and remains green until the pod is closed. Otherwise the pods remain dark.
The pods are detailed in Replica Brochure 4: