Wool symbolizes the lies carefully constructed to keep order in the silo.

When Juliette comes up with the idea of replacing the parts of the cleaning suit, she thinks of it as“[a] project to pull the wool back from everyone’s eyes” (191). In the sense that Juliette thinks it, wool represents the deception perpetrated on the residents of the silo, who think that IT makes a genuine effort to build cleaning suits to protect the cleaners, and on the cleaners themselves, who look through the wool of the helmet’s illusionary visor. Further, the cleaners use a scratchy wool pad to clean the camera sensors when they are outside. In this case, the wool represents the ritual of cleaning, which seemingly gives the people in the silo a clear view of the world, even as they continue to be deceived about the nature of their lives there.

Jahns’s knitting, a metaphor for the delicate society of the silo, also references the material, though she knits with cotton rather than wool (probably due to its rarity) and the subsequent section titles—"Proper Gauge,”“Casting Off,” and “The Unraveling”—draw on this symbolism. Bernard believes that pulling back the metaphorical wool as Juliette wants to do is a threat to everyone’s life, and the symbolic “unraveling” of order that occurs as the silo descends into fighting seems to support that view until Juliette’s return at the end of the novel.