Abstract: A scrubber configuration for controlling carbon dioxide levels in a shipping container containing respiring produce is disclosed. The scrubber is made up of a curtain which includes a gas-selective membrane having a CO2/O2 selectivity ratio greater than 1:1, said curtain being positioned close to and parallel with the rear wall of said container which includes a door, said curtain forming an air-tight seal dividing the interior of the container into a plenum chamber between said membrane and the (rear wall) door, and the remainder of the container in which the produce is placed. The structure also includes an air intake means for conveying fresh air from outside the container into the plenum chamber; and an air output means for conveying air from the plenum chamber to the outside of the container. A method for controlling the carbon dioxide levels inside a shipping container is also disclosed.