Patent ID: 7588231

Claim:
A valve for reducing emissions from a level gauge, said valve adapted to fit onto a level gauge for a vessel, said level gauge having a first interior cavity which is open when a thumbscrew is removed from the level gauge, said first interior cavity of the level gauge being in gaseous communication with an emission limiting bore in the level gauge, said valve comprising: a valve body with a threaded lower end, said lower end adapted to fit into said interior cavity of the level gauge when said thumbscrew is removed from the valve body to attach the valve to the level gauge; a second internal cavity defined in said valve body; a seating area disposed near the bottom of the second internal cavity; a bore disposed in the lower end of said valve body, said bore in the valve body being of substantially reduced cross-sectional area compared to the cross-sectional area of an emission limiting bore in the level gauge, said bore in the valve body providing gaseous communication between the lower end of the valve body and the second internal cavity; means for opening and closing said valve by permitting, or by not permitting, gaseous communication between said bore in the valve body and said second internal cavity; an orifice extending between said second internal cavity and an exterior surface of said valve body to vent gas or liquid from the second internal cavity when the means for opening or closing said valve permits gaseous communication between the bore in the valve body and the second internal cavity; means for blocking at least a portion of the venting passageway in the level gauge to prevent emissions from venting through the level gauge; and means for redirecting the emissions normally vented through the level gauge through a more restrictive bore in the valve body, thereby substantially reducing emissions from the level gauge while refilling the vessel.