JPH01209396A - Exposure dose managing apparatus - Google Patents

Abstract

PURPOSE:To determine an integral dose of radiation exposed to a worker at a high accuracy in real time, by obtaining a dose rate as function of position to plot the position of the worker. CONSTITUTION:A radiation source 2a in a working area 1 is set with a process equipment 2. A plurality of mat type position sensors 4 are provided to detect the existence of a worker. A detection signal is transmitted to a data processor 3. An entrance/exit door 7 for the working area 1 is provided with a door switch to start the data processor. A plurality of dose map monitor detectors 5 are arranged to determine a dose rate of the working area 1 as a whole as function of position from a data collected with a dose map scanner 6. The dose rate is calculated by inputting position coordinates of the worker into the function. An integral dose is transmitted to a dose display 10. This enables highly accurate measurement while real time display of a dose, thereby preventing excessive exposure.

Description

[Detailed Description of the Invention] [Object of the Invention] (Field of Industrial Application) This invention is applicable to 7i! ! This invention relates to a radiation exposure amount management device for managing individual radiation exposure in a facility.

(Prior Art) In a work environment where nuclear substances and radiation are handled, workers are required to measure and memorize the exposure dose, and to manage the exposure so that it does not exceed the maximum allowable II dose.

BACKGROUND ART Conventionally, in managing an individual's exposure dose, the measurement of the IIi ray matrix using a film batch, an area motor, etc. described below has been known.

A film badge is a case of special film that workers attach to their chests or waists when entering a room where radioactive materials are handled. The exposure dose can be determined by developing the film and measuring the degree of blackening after abalization.

In addition, the area monitor is FA+! It can be installed at several locations in a room where materials are handled, and the radiation dose rate at those locations, that is, the instantaneous radiation dose at a certain time, can be determined.

(Problem to be solved by the invention) However, in the film batch in the above conventional example,
Because radiation exposure is controlled after work, it is not possible to monitor radiation exposure during work in real time, and because the measuring equipment is small, it may be partially hidden behind objects, and the direction in which it detects radiation is poor. The disadvantage is that the measurement accuracy is poor.

Further, as mentioned above, the area monitor displays the radiation dose rate, and cannot know the cumulative exposure dose that indicates the total amount of radiation exposure. Furthermore, since the area monitor detects the radiation dose rate at the position of the detector, there is a problem in that it is not possible to accurately determine the radiation dose rate at the actual position of the worker.

This invention was made to solve such conventional problems, and its purpose is to calculate the radiation dose rate as a function of position and apply the position of the worker to this function. An object of the present invention is to provide a radiation exposure control device that can determine with high precision the accumulated radiation dose to which a worker is exposed, and can display this accumulated MtIi radiation dose in real time so that the worker can recognize it during work. .

[Structure of the invention] (Means for solving the problem) This invention was made to achieve the above object,
A radiation dose rate measuring means for measuring the radiation dose rate emitted from a radioactive substance at a predetermined position, a position detecting means for detecting the position of a worker entering a room where the radioactive substance is handled, and the radiation dose rate measuring means. By substituting into the pre-stored line ring equation from the radiation) one-line suspension rate obtained from the above-mentioned position detection means and the position of the worker obtained from the position detecting means, it is possible to determine the I product radiation (to) that the worker was actually exposed to. and an exposure dose display means for displaying the integrated radiation dose to which the worker was exposed in actual intercostal space based on the output result of the exposure dose calculation section.

(Operation) In this invention, the radiation dose rate in a room where radioactive materials are handled is determined as a function of position, and the accumulated radiation dose is determined by applying the worker's position coordinates to this function. radiation dose can be obtained.

Furthermore, since this integrated radiation dose is displayed in real time in a location that is easy for the worker to see, excessive exposure can be prevented.

(Example) FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, process equipment 2 that handles nuclear materials and radiation is installed in a work area 1, and two radiation sources 2a that are handled by this process equipment 2 are arranged.

In addition, in the work area 1, three mat-shaped position sensors 4 are installed to detect the presence of workers in places where workers constantly operate equipment or measure meters, that is, places where workers are present for a long time. It is set in place. The signal detected by this mat-shaped position sensor 4 is
The data is transmitted to a data processing device 3 installed outside the computer.

In order to determine the radiation dose rate of the entire work area 1 as a function of position, dose map monitor detectors 5 are provided at five locations.

The radiation dose rates obtained from these dose map monitor detectors 5 are transmitted to the data processing device 3 via the "fAffl map monitor scanner 6."

In addition, the door 7 through which workers enter and exit the work area 1 has a
When the worker enters the room, the door switch 8 is turned off, and when the worker leaves the room, the door switch 8 is turned off, and this signal is transmitted to the data processing device 3 as entry/exit information.

In this way, the above-mentioned information is taken into the data processing device 3, and the data processing I! 11 Control II performance nose part 9 inside the device 3
The integrated radiation dose is calculated at , and transmitted to a dose display 10 installed in a place easily visible to the worker in the work area 1, so that the integrated radiation 11i ray ω is displayed in real time. Further, if this integrated radiation dose exceeds the maximum allowable dose, the alarm 15 notifies the operator.

For this purpose, the data processing device 3 includes an input/output unit 11 that inputs given information and outputs data to be sent to the outside, and an RO unit that stores a system program for data processing in advance.
M12, a control calculation unit 9 that processes data obtained from the input/output unit using the system program, a RAM 13 that stores calculation data in the control calculation unit 9, and a CRT display 1 that displays calculation results obtained by the control calculation unit.
It consists of 4.

Next, the operation will be explained.

FIG. 2 is a flowchart showing the processing procedure of the control calculation section 9 in FIG.

When the worker enters the work area 1, the door switch 8 turns on "
When the data is transmitted to the control calculation unit 9 of the information data processing device, the program shown in FIG. 2 starts.

Then, the tIi ray generation rate detected by the line map monitor detector 5 is collected by the line portion map monitor detector dog 6 and sequentially read through the input/output unit 11 (step 1).

Further, the equation (1) representing the relationship between the magnitude R of the radiation dose rate and the measurement device is stored in M13.

R=A+C+/4π2((x-X, )2+N'-V+
)2) +A2℃2 /4π2((X −X 2 )2+(y−
y2)2) + ・・・・・・・・・ +△n Cn /4π2 ((x −xn) 2+
(y-yn) 2)
...(1) R: tll ray extent At (i = 1.2.-n): Coefficient Ci (
i=1.2.・n): i-th no hl DA line H
strength (xi, yi) (i = 1, 2...n)
: Coordinates of the first radiation source Therefore, by applying the read radiation dose rate R to equation (1), the coordinates of the radiation source (x1゜yl) and the measurement position (x, y) are known. Therefore, equations are obtained for the number of radiation dose rates R to be measured, that is, the number of lines 41 and map monitor detectors 5, and the coefficient Ai and the intensity Ci of the radiation source can be obtained.

The coefficient Ai and the intensity Ci of the radiation source are stored in the RAM 13 (step 2).

On the other hand, when the worker enters the work area 1 and works at the location where the mat-shaped position sensor 4 is installed, the position coordinates are read into the control calculation section 9 as described above (step 3).

Then, these position coordinates (x, y) are substituted into equation (1), and since the coefficient Ai1 and the intensity CI of the radiation source have already been determined, the radiation dose rate R is calculated (step 4). ).

Thereafter, this radiation dose rate R is accumulated, and the accumulated radiation fa
Ra is determined (step 5) and transmitted to the dose indicator 10 via the input/output unit 11, so that the worker is constantly notified of the integrated radiation dose to which the worker is exposed. At the same time, 6 is displayed on the CRT display 14 in the data processing device 3 (step 6).

It is determined whether this integrated radiation dose Ra exceeds the maximum allowable dose Rmax (step 7), and the maximum allowable line @
If Rmax is exceeded, the alarm device 15 will
A warning is given to the operator (step 8).

The above-mentioned operation is repeated until the exit information of the worker is obtained from the door switch 8, and when the worker exits, this calculation ends.

In this way, in this example, the radiation dose rate of one body in the work area is determined as a function of position, and the position coordinates of the worker are substituted into this to determine the radiation dose rate to which the worker is exposed. , the integrated radiation dose obtained by integrating these can be obtained with high precision.

Further, since this integrated radiation dose is displayed at a position easily seen by the worker in the work area 1, the worker can recognize the integrated radiation m in real time. Furthermore, if the integrated radiation ff1Ra exceeds the maximum permissible dose Rmax, a warning is issued, so excessive exposure can be reliably prevented and workers can work with peace of mind. .

Furthermore, although this embodiment is equipped with five dose map monitor detectors 5 shown in FIG.
It is preferable to provide the required number of holes at appropriate locations depending on the size of a, the size of the work area 1, etc. Similarly, the number of mat-shaped position sensors 4 to be installed may be determined depending on the working situation.

In addition, in this example, a door switch 8 was installed, but an ID card reader was installed in place of the door switch 8, and entry and exit from the work area 1 was controlled using the ID card carried by each worker. For example, it is possible to prevent unauthorized persons from entering the room.

Furthermore, if this ID card is configured with something with a memory function, such as an IC card, the cumulative radiation dose to which an individual worker was exposed can be stored not as temporary data but as long-term cumulative data. be able to. Besides, I
If the D card has an alarm function, and if the accumulated radiation dose Ra exceeds the maximum allowable dose RmaX, a warning will be issued and the worker will be prevented from entering the work area 1, resulting in higher safety. can be managed.

Furthermore, in order to detect the position of the worker in the work area 1, in addition to the mat-shaped position sensor →, for example, by attaching a detector to a chair and detecting that the worker is sitting on this chair, It is also possible to know the location of the worker.

Further, since light is run in the length and breadth of the work area 1 and the light is blocked when a worker is present, it is also possible to detect this with a light sensor and know the position of the worker.

Furthermore, in the case where there are a plurality of workers, it is possible to manage the plurality of workers simultaneously by providing identification means for each individual, such as a method of inputting the work position.

[Effect of the invention] As described above, according to the present invention, the radiation dose rate of the entire room where radioactive materials are handled is determined as a function of position, and the worker's position coordinates are applied to this function to determine the integrated radiation m. Therefore, it is possible to measure the integrated radiation dose with higher accuracy than conventional film batch or area monitors.

In addition, this integrated radiation dose is displayed in real time and the worker can directly view it, making it possible to prevent excessive exposure and facilitate self-management.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
It is a flowchart which shows the operation procedure in the control calculation part 11 in a figure. 3...Data processing device 4...Position sensor 5...Dose map monitor detector 8...Door switch 10...Line is indicator 15...Alarm

Claims (1)

[Scope of Claim] An apparatus for measuring the exposure dose of workers in a room where radioactive materials are handled, comprising a radiation dose rate measuring means for measuring the radiation dose rate emitted from the radioactive material at a predetermined position; A position detecting means for detecting the position of a worker entering the room, a radiation dose rate obtained from the radiation dose rate measuring means, and a position of the worker obtained from the position detecting means, which are stored in advance. An exposure dose calculation section that calculates the accumulated radiation dose that the worker was actually exposed to by substituting it into the calculation formula, and displays the accumulated radiation dose that the worker was exposed to in real time from the calculation results of the exposure dose calculation section. An exposure dose management device comprising: an exposure dose display means for displaying an exposure dose;