Radioactive gas monitor
AssigneeVictoreen, Inc.
InventorGeorge R. Utting
Life of this patent
Estimating the term…
Abstract
A radioactive gas monitor that is adapted to measure total airborne radiation activity over an extended period of time and provide a readout in units that can be directly correlated to the maximum permissible exposure standards established by the federal government. The instrument also includes automatic background count rate subtraction, as well as means for measuring the actual background radiation level and adjusting the subtracted count rate accordingly.
Claims20
A radioactive gas monitoring device for measuring the total airborne radiation activity in a designated area over an extended period of time and providing a direct readout of said measurement in predefined integrated units, including:
- a detector for detecting radioactive gas and producing a first pulsed output signal at a frequency that is proportional to the concentration of said radioactive gas;
- conversion means for converting said first pulsed output signal to a converted signal by dividing the frequency of said first pulsed output signal by a predetermined conversion factor so that each converted signal pulse corresponds to one of said integrated units, said conversion means including a first digital counter, a digital-to-analog converter for converting the digital output of said first digital counter to an analog signal, a comparator for comparing said analog signal to a reference signal and producing an output signal whenever the value of said analog signal is greater than the value of said reference signal, and calibration means for adjusting said predetermined conversion factor by adjusting the value of said reference signal;
- accumulator means for continuously accumulating the total number of converted signal pulses produced by said conversion means over the entire extended measurement period;
- and
- display means for displaying in said integrated units the total number of accumulated converted signal pulses.
A radioactive gas monitoring device for measuring the total airborne radiation activity in a designated area over an extended period of time and providing a direct readout of said measurement in MPC-HOUR units, including:
- a detector for detecting radioactive gas and producing a first pulsed output at a frequency that is proportional to the concentration of said radioactive gas;
- conversion means for dividing the frequency of said first pulsed output signal by a conversion factor corresponding to the number of pulses that would be produced by said detector in one hour if the level of radioactive gas concentration in said designated area was equal to the maximum permissible concentration (MPC) level, so that each pulse of said converted signal corresponds to one MPC-HOUR;
- accumulator means for continuously accumulating the pulses in said converted signal;
- and
- display means for displaying in MPC-HOUR units the total number of accumulated pulses.
A radioactive gas monitoring device for measuring the total airborne radiation activity in a designated area over an extended period of time, including:
- detector means for detecting radioactive gas and producing a detector output signal in accordance with the level of radioactive gas concentration in said designated area;
- accumulator means for continuously accumulating the information from said detector output signal including storage means for storing said accumulated information;
- display means for displaying said accumulated information;
- and
- standby means for suspending the further accumulation of information by said accumulator means without destroying the accumulated information in said storage means.
Dependencies are inferred from the claim text.