A hazard detection and suppression apparatus and a single-action discharge valve for discharging a vessel's contents. The valve has a valve body with a passage therethrough through which the contents are discharged, a frangible seal held within the valve body and sealing the passage while the seal is intact, and a solenoid including an armature moveable from a first to a second position. A thermopile or a thermopile matrix senses near-infrared energy to detect a fire hazard and actuate the valve. Amplifiers for the thermopile's signal are monitored for failure. A thermostat or a manual pushbutton can also actuate the valve, and an operator's panel monitors failure conditions. Other hazard detectors may be used including a petroleum detector, a chemical sensor, a moisture detector, a radiation detector, a gas detector, and a moving body detector.