A fire resistant, forced air cooled enclosure for one or more computer digital data storage devices is provided. An operable digital data storage device is mounted in a fire resistant enclosure. One or more openings are formed in the enclosure. A movable fire resistant hatch is positioned adjacent each of the openings and each hatch is movable between a closed position in which it closes the opening and an open position allowing ambient air to pass therethrough. A fan is positioned either inside or outside of the enclosure for actively driving ambient air through the opening to cool the data storage device. A hatch closure system is provided for closing each of said hatches automatically in the presence of a threshold temperature. The hatch closure system includes a temperature sensitive element which, when activated in the presence of the threshold temperature, causes the hatch to move to its closed position.