Embodiments of the present invention generally include a pressure relief system and methods of use, in which an apparatus includes an upper chamber fluidly connected to a pressurized fluid source, a lower chamber having an inlet and an outlet, a vertically moveable plate intermediate the chambers and disposed within a plate support, and connected to the plate by a vertical shaft, a vertically actuating lower chamber inlet valve including an inlet seal. Pressure relief is accomplished by controlling fluid pressure in the upper chamber such that varying downward force on the plate and therefore, via the shaft, the inlet seal, allows for selective opening/closing of the inlet valve as a function of upper chamber fluid pressure relative to the pressure exerted from a fluid source for which pressure relief is desired, beneath the inlet seal, whereby over-pressured fluid entering the lower chamber via the inlet is vented out the outlet.