Artist's conception of a Stanford Torus. [Source]
Consider a Stanford Torus of radius $ 4km $, with the inner radius of the torus ring being $1km$. Disregard structural stability issues. To simulate $1g$ of centripetal acceleration, it would rotate at around $0.5 rpm$ generating a rotational speed of ~$200m/s$ at the edge of the torus. This structure is then filled with air to maintain $1 atm$ of pressure, with a mixture of gases matching Earth's own atmosphere.
What would happen if the hull is punctured? How rapidly would air escape from the structure? How would this variable change depending on the size and location of the puncture? How long would it take for the entire structure to fully decompress?