Growth container and method for pathogenic and other laboratory organisms

Claim 1

A growth container for pathogenic and other laboratory organisms, comprising: a dish having a floor, an outer substantially closed wall extending upward from the floor, and an inner substantially closed wall spaced inward from the outer wall and extending upward from the floor to a height less than that of the outer wall, the inner wall and subtended floor forming a well for a growth medium, a lid adapted to fit over the outer wall of the dish to substantially close the container, a blocking ring depending from the lower surface of the lid over the space between the inner and outer dish walls, the ring blocking and accumulating the outward flow of condensation along the lower lid surface so that an excess of condensation drips into the space between the inner and outer dish walls, and a sufficient quantity of a liquid absorbent material in the space between the inner and outer walls to humidify the interior of the container when the absorbent material is wet and the container is closed, and to prevent condensation dripped from the blocking ring from re-entering the growth medium well, whereby the growth medium is protected from both insufficient and excess moisture, the liquid absorbent material comprising a vertically movable absorbent filter ring disposed in the space between the inner and outer dish walls, the filter adapted to move through the container to contact and absorb moisture from the blocking ring when the container is inverted, and to return to its original position when the container is returned to an upright position.

Claim 3

A method of growing a pathogenic organism which is subject to excess condensation when grown in an enclosed petri dish, comprising the steps of: placing a growth medium for the organism in a well, substantially surrounding the well with a liquid absorbent material comprising a filter ring which is vertically movable within the enclosure, substantially enclosing the well and liquid absorbent material with a lid that is spaced above the well, collecting outward flowing condensation on the lower side of the lid along a locus which is vertically aligned with the liquid absorbent material, inverting the enclosure so that the filter ring falls to the lid and absorbs condensation along the locus, again inverting the enclosure to return the filter ring to its original position, and retaining excess collected condensation dripped onto the filter ring in the filter material to prevent it from re-entering the growth medium.

Claim 4

A method of growing a pathogenic organism which is subject to excess condensation when grown in an enclosed petri dish, comprising the steps of: placing a growth medium for the organism in a well, substantially surrounding the well with a liquid absorbent material comprising a filter ring which is vertically movable within the enclosure, substantially enclosing the well and liquid absorbent material with a lid that is spaced above the well, collecting outward flowing condensation on the lower side of the lid along a locus which is vertically aligned with the liquid absorbent material, inverting the enclosure so that the filter ring falls to the lid and absorbs condensation along the locus, again inverting the enclosure to return the filter ring to its original position, and retaining excess collected condensation dripped onto the filter ring in the filter material to prevent it from re-entering the growth medium.