Abstract: The gas detection apparatus for detecting chemical agents in an air stream includes a radioactive source to ionize the air stream and an electrostatic field to increase the efficiency of the apparatus by neutralizing undesired ions, which allows a radioactive source with a lower radiation level to be used than would be required without such neutralization. A diffusion chamber including a baffle device is then used for an ion selection processes. Additional undesired ions are diffused into the walls of the diffusion chamber while the remaining ions, which are the ones sought to be detected, pass from the diffusion chamber into a collection chamber. Detection of the chemical agent ions is achieved when the remaining ions collide with the walls of a collection chamber, transferring their charge to thereby generate a current.

Abstract: Described is a control circuit or energizing circuit for a series field mr. To limit the surge of inrush startup current to no greater than the steady-state running current, a series string of three thermistors is inserted in series with the motor. The thermisters have negative temperature coefficient, and have nominally equal ratings and values. The circuit has application in motor/blower systems.

Abstract: A gas particulate filter system is provided for supplying clean heated air o an operator subjected to ambient environments containing nuclear, biological or chemical contaminants. The filter unit includes replaceable radial flow canister means, centrifugal blower/heater means, continuously variable electronic control means for regulating air temperature and air flow, and clamping means for easy assembly of the components under adverse field conditions.