Spark detection and extinguishing systems detect and extinguish a spark or burning ember in under 300 milliseconds. Detecting a spark in a pneumatic material transport duct at speeds that often exceed 25 meters per second requires a very sensitive and very fast sensing device. High speed infrared detectors that actually count sparks can quickly actuate a suppression system that utilises water, CO² or other extinguishing agent of choice to effectively protect the operating plant from fires and explosions. The detectors automatically and immediately reset themselves so that they stand ready to detect any possible subsequent sparks.