Abstract: A vent line protection device to protect the vent of a gas regulator from a predetermined water level, including a vertically-oriented housing having an upper portion including vent line connection and an atmospheric vent opening, and a lower portion including a water opening, the vent line connection being adapted to connect to the vent of the gas regulator, and a float disposed inside the housing and being movable in a vertical direction within the housing, an upper end of the float including a seal adapted for scaling off the vent line connection, wherein when the water level is lower than the predetermined level, gas can flow through the housing between the vent line connection and the atmospheric vent opening, and wherein when the water level is at or higher than the predetermined level, the vent line connection is scaled off by the seal of the float.