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.
