Ventilating hatch assembly

A ventilating and escape hatch assembly for selectively providing ventilation to the space below a substantially horizontal deck or the like as well as an escape passage therefrom, comprising a square opening in the deck, a coaming around said opening having a square plan configuration, said coaming extending substantially above the deck and being permanently secured thereto in water-tight sealed relation therewith, a square hatch frame demountably disposed in cooperative mating relation with said coaming, said coaming and hatch frame having accurately square dimensions permitting the selective 90.degree. or 180.degree. repositioning of said frame with respect to said coaming, a hatch cover pivotally attached along one edge thereof to one side of said frame for selective rotation with respect thereto about a substantially horizontal axis, and quick release means actuatable from below said deck for detachably securing said frame to said coaming thereby permitting said frame and attached cover to be quickly removed to provide an escape passage or to be repositioned with respect to said coaming for optimal ventilation.