Monitor system for potentially hazardous radiation and combustion conditions

A hazardous condition monitoring system is described which consists of: a vessel having a chamber, an input port, and an output port therein for passing atmosphere along a flow path through the chamber, a radiation sensor mounted in one of the ports and disposed in the flow path through the vessel for sensing changes in atmospheric conditions in the chamber, and for providing electrical output signals therefrom. The radiation sensor has a common electrical input-output path, and being responsive to impinging energetic nuclear particles of radiation in the atmosphere passed through the vessel to provide a changed electrical output potential therefrom; annunciation means; detection means coupled to the radiation sensor for detecting a predetermined change in the electrical output potential. The detection means is coupled to provide an output to the annunciation means, the annunciation means being coupled to receive the detection means output and providing annunciation indicative of presence of excessive nuclear radiation passing through the vessel when a predetermined threshold is exceeded. The threshold is indicative of the occurance of a hazardous condition; first and second valves disposed respectively in the input and output ports for opening and closing both ports to periodically seal the chamber from external atmospheric conditions, and control means for simultaneously operating the valves