An animal accommodation facility is described including: a number of substantially airtight enclosures each enclosure having at least one air inlet and at least one air outlet an air delivery system which draws air from the atmosphere an air exhaust system which exhausts air to the atmosphere wherein the air delivery system delivers air to the at least one air inlet of each enclosure and the air exhaust system receives air from the at least one air outlet of each enclosure wherein the air delivery system includes a number of air delivery conduits and at least one air delivery conduit is dedicated to each enclosure and wherein the air exhaust system includes a number of air exhaust conduits and at least one air exhaust conduit is dedicated to each enclosure.
