“Fire-rated” Hatches with Glazed and Clamped Doors
This design of hatch has two framed doors glazed in either a half hour integrity fire resistance ‘pyrobelite’ clear laminated glass or one hour integrity fire resistance ‘Schott Pyran’ toughened borosilicate clear class which open on surface mounted stainless steel cast hinges.
Each door is fitted down one edge with a rubber edging seal which allows the doors to be clamped closed by the action of turning the knobbed lever, on the door, until it locates and slides into the angled receiver on the outside face of the hatch.
Pass Through Hatches with Glazed and Clamped Doors
This design of hatch would have two framed doors glazed in either 6.4mm thick clear laminated glass or 6mm thick clear toughened glass, which open on surface mounted stainless steel cast hinges.
These doors are deliberately not sealed in order to allow a small volume of air from the clean side (which is normally at a higher pressure) to continuously flush the interior of the hatch. This volume is relatively small by comparison with room air flows, that, it should have no perceptible effect on room pressures.
A pass-through hatch designed with the doors on the adjacent walls of the hatch. This design is especially suited for fitting in the corner of a room, or where access would be restricted by parallel access doors.