A high speed scanning system and method for scanning a matrix of alarm condition sensing means. A clock-fed counter means and decoder means automatically scan the matrix line by line. When a sensing means which has turned on due to the detection of an alarm condition is sensed the scanning means automatically stops scanning and a readout of the matrix position of the triggered alarm sensing means is provided. The scanning operation may be controlled in either an automatic mode by a central porcessing unit or in a manual mode by switches located on a control panel. The scanning operation may be stopped or started, the counters may be cleared or loaded and the current scanned matrix position may be read out.