I had a thought about what the operating air pressure of the ISS would be. I was surprised to find it is 1 atmosphere or 14.7 psi.
Given that airliners fly in the lower atmosphere but pressurise cabins at about 11 or 12 psi (and fly at altitudes producing a pressure differential of a half atmosphere), what is the rationale for the ISS to maintain a whole atmosphere difference against the vacuum?