Abstract: A radiation measurement device having a radiation detector, a measurement instrument provided with a signal conversion unit for carrying out signal conversion on a detection current signal output from the radiation detector, and a signal input line for supplying the detection current signal output from the radiation detector to the signal conversion unit, wherein if a test mode is selected, a test current signal is superposed on the detection current signal and supplied to the signal conversion unit through the closing of contacts and the connection of a constant-voltage source and the signal input line, and if a normal mode is selected, the constant-voltage source is connected to a point having the same potential as the signal input line and the generation of a potential difference between the contacts is prevented through the opening of the contacts and the disconnection of the constant-voltage source and signal input line.

Abstract: A radiation measurement device having a radiation detector, a measurement instrument provided with a signal conversion unit for carrying out signal conversion on a detection current signal output from the radiation detector, and a signal input line for supplying the detection current signal output from the radiation detector to the signal conversion unit, wherein if a test mode is selected, a test current signal is superposed on the detection current signal and supplied to the signal conversion unit through the closing of contacts and the connection of a constant-voltage source and the signal input line, and if a normal mode is selected, the constant-voltage source is connected to a point having the same potential as the signal input line and the generation of a potential difference between the contacts is prevented through the opening of the contacts and the disconnection of the constant-voltage source and signal input line.

Abstract: A dose rate monitoring device contains a first radiation detector including an inorganic crystal scintillator, a second radiation detector including a plastic scintillator, a detector mount having a cylinder part, a low range calculator calculating a first compensation dose rate of an incident radioactive ray based on the detection signal pulse, a high range calculator calculating a second compensation dose rate of an incident radioactive ray based on the detection signal pulse, a dose rate calculator calculating a dose rate ratio from the first compensation dose rate and the second compensation dose rate, and choosing a compensation dose rate according to the magnitude of the calculated dose rate ratio; and a display displaying the compensation dose rate which is outputted from the dose rate calculator, wherein the plastic scintillator which is included in the second radiation detector is wound around the cylinder part of the detector mount.

Abstract: A dose rate monitoring device includes: a first energy compensation coefficient operation part obtaining a first energy compensation coefficient to incident radiation using the first compensation coefficient table, a first dose rate operation part obtaining a first compensation dose rate of incident radiation using the first energy compensation coefficient and G (E) function, a second energy compensation coefficient operation part obtaining a second energy compensation coefficient to incident radiation using a second compensation coefficient table, a second dose rate operation part obtaining a second compensation dose rate of incident radiation using a second energy compensation coefficient, a dose rate switching section which select an output according to the magnitude of a ratio of the first compensation dose rate to the second compensation dose rate, and a display operating section which displays the first compensation dose rate or the second compensation dose rate which the dose rate switching section out

Abstract: A dose rate monitoring device contains a first radiation detector including an inorganic crystal scintillator, a second radiation detector including a plastic scintillator, a detector mount having a cylinder part, a low range calculator calculating a first compensation dose rate of an incident radioactive ray based on the detection signal pulse, a high range calculator calculating a second compensation dose rate of an incident radioactive ray based on the detection signal pulse, a dose rate calculator calculating a dose rate ratio from the first compensation dose rate and the second compensation dose rate, and choosing a compensation dose rate according to the magnitude of the calculated dose rate ratio; and a display displaying the compensation dose rate which is outputted from the dose calculator, wherein the plastic scintillator which is included in the second radiation detector is wound around the cylinder part of the detector mount.

Abstract: Three semiconductor detectors are installed at positions where incidence of radiation on a scintillation detector is not blocked, at equal intervals centered on a central axis of the scintillation detector and at equal angles with respect to a plane which is at a right angle to the central axis. An energy compensation factor is determined on the basis of an average pulse height value obtained from a second pulse height spectrum obtained by analog voltage pulses which are output from these semiconductor detectors, and energy characteristics of a high-range dose rate obtained by a direct-current voltage which is output from the scintillation detector are compensated for.

Abstract: A radiation monitoring device includes: a scintillator emitting fluorescence upon absorption of radiation, a photo-multiplier tube converting the fluorescence into an electron pulse, a preamplifier converting the electron pulse into an analog voltage pulse, a pulse amplifier amplifying the analog voltage based on a gain control value, a dose rate measurement part measuring a dose rate based on an output of the pulse amplifier, an average half width measurement part, measuring a half width of a voltage pulse, which is among the outputs of the pulse amplifier and has a wave height larger than a preset value, and processing a predetermined number of measured data on the half widths to calculate a half width deviation, a gain control part receiving the half width deviation from the average half width measurement part, and determining the gain control value using a table, which lists relations between half widths and temperature calibration factors.

Abstract: A dose rate monitoring device includes: a first energy compensation coefficient operation part obtaining a first energy compensation coefficient to incident radiation using the first compensation coefficient table, a first dose rate operation part obtaining a first compensation dose rate of incident radiation using the first energy compensation coefficient and G (E) function, a second energy compensation coefficient operation part obtaining a second energy compensation coefficient to incident radiation using a second compensation coefficient table, a second dose rate operation part obtaining a second compensation dose rate of incident radiation using a second energy compensation coefficient, a dose rate switching section which select an output according to the magnitude of a ratio of the first compensation dose rate to the second compensation dose rate, and a display operating section which displays the first compensation dose rate or the second compensation dose rate which the dose rate switching section out

Abstract: In a radiation measurement device in which respective wave height values of voltage pulses from a radiation detector are made to correspond to radiation energy values and a count that is the number of the voltage pulses is separately generated for each of a plurality of channels corresponding to the wave height values so that a wave height spectrum is generated and a dose of a radiation that has entered the radiation detector is calculated based on the wave height spectrum, based on a count in at least one channel, out of the plurality of channels, that includes a lower limit within a measurement range for the radiation energy value, a dose is corrected by calculating a portion thereof neglected as what is the same as or smaller than a measurement limit, so that a dose of a radiation that has entered the radiation detector is calculated.

Abstract: Three semiconductor detectors are installed at positions where incidence of radiation on a scintillation detector is not blocked, at equal intervals centered on a central axis of the scintillation detector and at equal angles with respect to a plane which is at a right angle to the central axis. An energy compensation factor is determined on the basis of an average pulse height value obtained from a second pulse height spectrum obtained by analog voltage pulses which are output from these semiconductor detectors, and energy characteristics of a high-range dose rate obtained by a direct-current voltage which is output from the scintillation detector are compensated for.

Abstract: The radiation monitor includes: a shutter; a calculation section; an AC solenoid; a temperature switch which is attached to the AC solenoid; a circuit protector which has a contact and is connected in series to the AC solenoid; and a mode selection switch connected in series to the AC solenoid. The shutter is maintained in a closed state when the mode selection switch is set to a normal mode; the mode selection switch is changed from the normal mode to a check radiation source mode, thereby flowing an AC current through the AC solenoid to change the shutter from the closed state to an opened state; and the contact of the temperature switch is reversed from the opened state to the closed state, thereby disconnecting the contact of the circuit protector to interrupt the AC current that flows through the AC solenoid.

Abstract: A radiation monitoring device includes: a scintillator emitting fluorescence upon absorption of radiation, a photo-multiplier tube converting the fluorescence into an electron pulse, a preamplifier converting the electron pulse into an analog voltage pulse, a pulse amplifier amplifying the analog voltage based on a gain control value, a dose rate measurement part measuring a dose rate based on an output of the pulse amplifier, an average half width measurement part, measuring a half width of a voltage pulse, which is among the outputs of the pulse amplifier and has a wave height larger than a preset value, and processing a predetermined number of measured data on the half widths to calculate a half width deviation, a gain control part receiving the half width deviation from the average half width measurement part, and determining the gain control value using a table, which lists relations between half widths and temperature calibration factors.

Abstract: A radiation monitor includes an AC control section and a DC control section. The AC control section outputs an AC power source instantaneous power failure detection signal to the DC control section when a decrease in AC voltage is detected. The DC control section measures a duration time of an AC power source instantaneous power failure detection signal when the AC power source instantaneous power failure detection signal is received from the AC control section and outputs an instantaneous power failure restart signal to the AC control section if the AC voltage is restored within a time shorter than a set value. The AC control section performs switching control from close to open of the sampling solenoid valve, the purge solenoid valve, and the exhaust solenoid valve, and restarts the pump after a constant time when the instantaneous power failure restart signal is received from the DC control section.

Abstract: A radiation monitoring device comprises a radiation monitor and a test unit for testing the radiation monitor. The radiation monitor includes a radiation detector and a measurement unit. The test unit includes a test pulse generator and a test pulse controller. The measurement unit includes a counter circuit, a computing part that computes a count rate with the standard deviation kept constant, an input switching circuit. When a test mode is selected in the radiation monitor, the test pulse controller changes the repetition frequency of test pulses in a step-function manner to the same repetition frequency of a start count rate specified as reference, replaces a count rate in the computing part at current computing cycle with the start count rate, switches the input switching circuit to the test pulse input at next computing cycle to start the test, and then finishes the test after a predetermined time elapses.

Abstract: The radiation monitor includes: a shutter; a calculation section; an AC solenoid; a temperature switch which is attached to the AC solenoid; a circuit protector which has a contact and is connected in series to the AC solenoid; and a mode selection switch connected in series to the AC solenoid. The shutter is maintained in a closed state when the mode selection switch is set to a normal mode; the mode selection switch is changed from the normal mode to a check radiation source mode, thereby flowing an AC current through the AC solenoid to change the shutter from the closed state to an opened state; and the contact of the temperature switch is reversed from the opened state to the closed state, thereby disconnecting the contact of the circuit protector to interrupt the AC current that flows through the AC solenoid.

Abstract: A radiation monitor includes a high-energy count-rate-measurement functional unit, a low-energy count-rate-measurement functional unit, and an alert-diagnosis functional unit. The alert-diagnosis functional unit receives an alert from the high-energy count-rate-measurement functional unit, receives a low-energy count rate from the low-energy count-rate-measurement functional unit, determines whether or not the low-energy count rate is in a set acceptable range by performing synchronizing with alert transmission, determines that the alert is caused by fluctuation, when the low-energy count rate is in the acceptable range, determines that the alert is caused by any of an increase in the ? ray which is a measurement target or enter of noise, when the low-energy count rate is increased beyond the acceptable range, and outputs results of determination.

Abstract: A shield has a detector installing hole having a central axis orthogonal to a central axis of a detection tube. A radiation sensor of a columnar scintillation detector to which a low concentration side measurement range within all required measurement ranges is allocated is arranged inside the detector installing hole. An ionization chamber to which a high concentration side measurement range is allocated is arranged side by side in parallel with the detection tube. The measurement range of the columnar scintillation detector and the measurement range of the ionization chamber are adjusted so as to be overlapped with each other.

Abstract: A radiation monitor includes an AC control section and a DC control section. The AC control section outputs an AC power source instantaneous power failure detection signal to the DC control section when a decrease in AC voltage is detected. The DC control section measures a duration time of an AC power source instantaneous power failure detection signal when the AC power source instantaneous power failure detection signal is received from the AC control section and outputs an instantaneous power failure restart signal to the AC control section if the AC voltage is restored within a time shorter than a set value. The AC control section performs switching control from close to open of the sampling solenoid valve, the purge solenoid valve, and the exhaust solenoid valve, and restarts the pump after a constant time when the instantaneous power failure restart signal is received from the DC control section.

Abstract: A radioactive gas monitoring device includes a sample chamber into which a sampled gas is introduced; a plastic scintillation detector outputting first detection signal pulses; an inorganic crystal scintillation detector outputting second detection signal pulses; a first measurement unit calculating a first count rate from the first detection signal pulses to output the first count rate, and issuing a first alert when the first count rate becomes higher than a first preset level and issuing a second alert when the first count rate becomes higher than a second preset level higher than the first preset level; and a second measurement unit calculating a second count rate from the second detection signal pulses to output the second count rate, and issuing a third alert when the second count rate becomes higher than a third preset level.

Abstract: A radiation monitor includes a high-energy count-rate-measurement functional unit, a low-energy count-rate-measurement functional unit, and an alert-diagnosis functional unit. The alert-diagnosis functional unit receives an alert from the high-energy count-rate-measurement functional unit, receives a low-energy count rate from the low-energy count-rate-measurement functional unit, determines whether or not the low-energy count rate is in a set acceptable range by performing synchronizing with alert transmission, determines that the alert is caused by fluctuation, when the low-energy count rate is in the acceptable range, determines that the alert is caused by any of an increase in the ? ray which is a measurement target or enter of noise, when the low-energy count rate is increased beyond the acceptable range, and outputs results of determination.