A valve assembly comprising: a valve with a valve body and a chamber; a poppet positioned in the valve and slidably engaged with the valve body, wherein the poppet comprises a stem and a piston; a poppet release mechanism for releasing the poppet from a closed position; the valve assembly being characterised in that it further comprises: a mechanism cover attached to the valve body; and a safety mechanism for preventing the poppet from moving into a fully open position unless the safety mechanism is disengaged, wherein the safety mechanism comprises: a pin positioned such that a first end of the pin extends into the chamber of the valve into a pathway of the poppet and a second end of the pin extends into the valve body; a spring positioned between and in contact with the pin and the mechanism cover, wherein the spring biases the pin toward the poppet; and a lever, wherein a first end of the lever is pivotably attached to the pin and a second end of the lever extends out from the valve body so that the lever will maintain the pin in a blocking position until the second end of the lever is pushed and the first end of the lever translates the pin out of a blocking position and into an un-blocking position. a valve with a valve body and a chamber; a poppet positioned in the valve and slidably engaged with the valve body, wherein the poppet comprises a stem and a piston; a poppet release mechanism for releasing the poppet from a closed position; the valve assembly being characterised in that it further comprises: a mechanism cover attached to the valve body; and a safety mechanism for preventing the poppet from moving into a fully open position unless the safety mechanism is disengaged, wherein the safety mechanism comprises: a pin positioned such that a first end of the pin extends into the chamber of the valve into a pathway of the poppet and a second end of the pin extends into the valve body; a spring positioned between and in contact with the pin and the mechanism cover, wherein the spring biases the pin toward the poppet; and a lever, wherein a first end of the lever is pivotably attached to the pin and a second end of the lever extends out from the valve body so that the lever will maintain the pin in a blocking position until the second end of the lever is pushed and the first end of the lever translates the pin out of a blocking position and into an un-blocking position. a mechanism cover attached to the valve body; and a safety mechanism for preventing the poppet from moving into a fully open position unless the safety mechanism is disengaged, wherein the safety mechanism comprises: a pin positioned such that a first end of the pin extends into the chamber of the valve into a pathway of the poppet and a second end of the pin extends into the valve body; a spring positioned between and in contact with the pin and the mechanism cover, wherein the spring biases the pin toward the poppet; and a lever, wherein a first end of the lever is pivotably attached to the pin and a second end of the lever extends out from the valve body so that the lever will maintain the pin in a blocking position until the second end of the lever is pushed and the first end of the lever translates the pin out of a blocking position and into an un-blocking position. a pin positioned such that a first end of the pin extends into the chamber of the valve into a pathway of the poppet and a second end of the pin extends into the valve body; a spring positioned between and in contact with the pin and the mechanism cover, wherein the spring biases the pin toward the poppet; and a lever, wherein a first end of the lever is pivotably attached to the pin and a second end of the lever extends out from the valve body so that the lever will maintain the pin in a blocking position until the second end of the lever is pushed and the first end of the lever translates the pin out of a blocking position and into an un-blocking position.