Abstract: The present invention discloses a combination sampling and pressure relief valve. In particular embodiments, the valve includes a main body having a central bore therethrough, the central bore having first and second chamfered surfaces; a front surface having an aperture in communication with the central bore; and a rear surface having an aperture in communication with the central bore; a valve seat/stem assembly located within the central bore, the valve seat/stem assembly having first and second chamfered surfaces that are complementary to the main bore chamfered surfaces; a spring extending between the valve seat/stem assembly and a rear end cap of the valve; and, a drain aperture extending perpendicularly from the central bore to ambient, the drain aperture located between the central bore first and second chamfered surfaces. Other embodiments of the valve are disclosed.