The YeeValve TT8178 Emergency Relief Valve, a Weight Loaded, Hinged Emergency Pressure Relief Valve series, is designed for applications requiring low fugitive emissions and operation around the maximum allowable working pressure of storage tanks. This full-lift type valve is engineered to activate fully and stably at just 10% overpressure. Like all YeeValve pressure/vacuum relief valves, the TT8178 functions as a regulating valve with a venting rate near zero, which means it can reset at the designated pressure. This efficiency is achieved through the precise integration of the nozzle, seat, and pallet, ensuring that the valve initiates a complete and stable response when the pressure or vacuum slightly exceeds the set threshold by only 10%.