Patent ID: 8177883

Claim:
A container comprising: a plurality of walls; and at least one inlet and/or outlet; and an apparatus for controlling the composition of gases within the container, the apparatus including: at least one sensor configured to determine a gas composition; at least one controller; and at least one gas permeable membrane, through which membrane different gases pass at different rates, said membrane dividing the container into a first region being for holding cargo and a second region defining a gas buffer region, and said membrane being permeable permitting for nitrogen, oxygen and carbon dioxide at different flow rates, wherein the gas buffer region is in communication with an ambient atmosphere through one or more vacuum pumps, wherein the at least one controller is configured to activate and deactivate the one or more vacuum pumps in response to a sensed composition of gas within the first region, and wherein the one or more vacuum pumps are activated to lower a concentration of carbon dioxide and oxygen within the container to below 21%.