Patent attributes
Rectangular or circular vent apparatus for protecting a confined space having a vent aperture for relief of an overpressure condition is provided with each including vent structure having a vent unit adapted to be positioned over the vent aperture in normal closing relationship thereto. Each vent unit preferably includes at least one spring steel panel, or spring steel leaves positioned against a metal sheet, provided with a movable pressure relief portion having an initial position extending across the vent aperture. A backstop is provided for arresting the degree of movement of the spring steel. The spring steel panel or the spring steel leaves have a sufficient modulus of resilience and elasticity to cause the relief portion of the spring steel panel or the metal sheet to return to their respective initial positions from the open positions thereof upon relief of the overpressure condition in the confined space.
