A passive fire response system is configured to suppress a metallic fire. The system includes a reservoir containing an ionic liquid, at least one outlet in communication with the reservoir, a valve arranged between the reservoir and the outlet, a sensor configured to sense at least one of a hydrogen concentration and a temperature and/or heat, and a controller configured to open the valve and release the ionic liquid if an output from the sensor indicates that the at least one of the hydrogen concentration and the temperature equals or exceeds at least one of a threshold hydrogen concentration and a threshold temperature.