JP6944633B2 - Radiation leak inspection system - Google Patents

Description

The present invention relates to a radiation leakage inspection method and a radiation leakage inspection system, and more particularly to an inspection technique for confirming and inspecting the presence or absence of radiation leakage in radiation shielding work.

Conventionally, medical institutions such as hospitals perform examinations and treatments using radiation such as X-rays. Radiation clinics where such examinations and treatments are performed using radiation are inside partitions such as walls, floors, ceilings, and doors so that radiation does not leak to the surrounding rooms (including corridors and floors above and below). Radiation shielding work is being carried out by arranging a shielding material (for example, a lead plate) that shields radiation.

Then, in this type of radiation shielding work, a radiation leakage inspection is performed to confirm the presence or absence of radiation leakage after the work.

Conventionally, in this radiation leakage inspection, a radiation generator that generates radiation (for example, X-rays) is placed in the radiation clinic, and the amount of radiation that penetrates the partition between the radiation clinic and walls, floors, ceilings, doors, etc. Is measured using a measuring instrument such as a survey meter. For example, in an inspection in a room adjacent to a radiological clinic with a wall, the measured value of the survey meter is monitored while moving the survey meter along the wall surface on which the radiation shielding material is arranged, and the measured value is a predetermined value. The worker confirmed and judged whether or not it exceeded (the standard value for judging the presence or absence of radiation leakage).

However, such a method is complicated because the worker must always check the measured value.

In addition, among the poor construction of the radiation shielding material, for example, unexpected holes may be drilled in the radiation shielding material due to wiring work, etc., and in the case of such local poor construction, radiation is emitted by the measuring instrument. It was difficult to find the leak. That is, since the radiation (including scattered rays) emitted from the radiation generator has high straightness, if there is a local hole in the radiation shielding material, the radiation is not at the position facing the hole. Leakage cannot be detected. Therefore, in the inspection while moving the measuring instrument, there is a possibility that an inspection omission may occur.

Therefore, the applicant has proposed an inspection method using the inspection device a shown in FIG. 4 (see Patent Document 1). In this inspection method, as the inspection device a, an inspection device a in which a plurality of radiation measuring instruments (for example, survey meters) b, b, ... Are arranged in a row in a housing d provided with wheels c is used.

In the inspection, a radiation generator is placed in the radiation clinic, and the radiation measuring instruments b, b, ... Are placed facing each other on the wall surface of the room adjacent to the radiation clinic with the radiation shielding material in between. , While moving the inspection device a along the wall surface, inspect the presence or absence of transmitted radiation (radiation leakage) passing through the wall surface.

Japanese Unexamined Patent Publication No. 2015-102480

However, such a radiation leakage inspection method has the following problems, and it is necessary to improve them.

The inspection method using the inspection device a shown in FIG. 4 quickly inspects the entire wall surface by simply moving the inspection device a along the wall surface, that is, a wide range of inspections that cannot be covered by a local inspection using a single survey meter. Although it has the advantage that it can be easily performed, there is a problem that the possibility of inspection omission cannot be completely eliminated because a gap is created between the radiation measuring instruments b and b due to the structure of the apparatus. There is.

The present invention has been made in view of such problems, and an object of the present invention is to provide a radiation leakage inspection system capable of performing a wide range of inspections quickly and easily and having few inspection omissions. To do.

In order to achieve the above object, in the radiation leakage inspection system according to the present invention, a radiation generator that generates radiation for inspection is arranged in a room where radiation shielding work has been performed, and the radiation generator and a radiation shielding material are sandwiched between them. With the surface on the opposite side as the inspection surface, the inspection surface is scanned while moving the line sensor camera with respect to this inspection surface, and the transmitted radiation image of the inspection surface is displayed on the display device. A radiation leakage inspection system for implementing a radiation leakage inspection method that visually confirms the position of defective parts of radiation shielding work on the above display device . A portable radiation generator and a portable line sensor camera. And a display device that displays a transmitted radiation image of the entire surface of the inspection surface or a predetermined range based on the transmitted radiation data taken by the line sensor camera, the line sensor camera has a grip portion that can be held with one hand. It is characterized by having.

According to the present invention, if there is a defective part in the radiation shielding work, an image of the radiation transmitted through the defective part is displayed on the screen of the display device, so that the worker performing the inspection can display the image on the screen of the display device. By examining the presence or absence of a portion showing radiation transmission, it is possible to easily confirm whether or not there is a defective portion in the radiation shielding work.

In addition, since the inspection is performed by moving the line sensor camera, it is possible to inspect the surface having a certain width (sensing width of the line sensor camera) without omission, and prevent the occurrence of inspection omission. Becomes possible.

It is explanatory drawing which shows the schematic structure of the radiation leakage inspection system which concerns on this invention. It is a top view which shows the arrangement example of the X-ray generator in the radiation leakage inspection system. It is explanatory drawing which shows an example of the scanning procedure of the wall surface by the radiation leakage inspection system. It is explanatory drawing of the inspection apparatus for the conventional radiation leakage inspection.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Embodiment 1
FIG. 1 shows a schematic configuration of a radiation leakage inspection system according to the present invention. FIG. 1 shows an X-ray leakage inspection system 1 that performs an X-ray leakage inspection, and as shown in the figure, mainly includes an X-ray generator (radiation generator) 2, a line sensor camera 3, and a display device 4. It is organized as a department.

The X-ray generator 2 is composed of a portable small X-ray generator. The X-ray generator 2 has a structure in which an X-ray generating portion (not shown) is surrounded by a cover made of an X-ray shielding material such as a lead plate, and an opening is provided at a specific position of the cover. Therefore, X-rays are emitted to the outside from the opening. By arranging the phantom on the irradiation surface, scattered X-rays are generated on the entire surface of the room where the X-ray generator 2 is arranged.

The line sensor camera 3 is a device for converting the amount of X-ray transmission into image data, and as is well known, a sensor main body 5 having a plurality of light receiving elements and a power supply device for supplying electric power to the sensor main body 5. (Not shown) and an interface cable 6 for supplying the image data acquired by the sensor main body 5 to the display device 4 are configured as main parts.

The sensor body 5 is formed by arranging a plurality of light receiving elements (for example, scintillators, semiconductors, CCDs, etc.) in a row on a one-dimensional line, and the light receiving elements are placed outside the housing in a substantially box-shaped housing. It is configured by arranging the light receiving elements toward the surface, and has a horizontally long shape with the arrangement direction of the light receiving elements as the longitudinal direction. The sensor body 5 is configured to output image data according to the transmitted X-ray dose, for example, image data of shading according to the amount of transmitted X-rays via the interface cable 6.

In the present embodiment, the sensor main body 5 is composed of a portable device that can be carried by an operator, and is configured to have a size that allows the operator to hold and handle at least with both hands or one hand. Specifically, the longitudinal dimension of the sensor body 5 is about several tens to several hundreds of cm, preferably about several tens of cm (for example, about 50 cm) that can be handled with one hand.

As the sensor body 5, for example, a commercially available X-ray line sensor used for inspection of the presence or absence of foreign matter (non-destructive X-ray inspection) is preferably used. By using a commercially available X-ray line sensor in this way, it is possible to provide the X-ray leakage inspection system 1 according to the present invention at low cost.

Further, the sensor main body 5 is provided with a grip portion (not shown) for an operator to hold the sensor main body 5 with both hands or one hand. This grip portion is a portion provided to facilitate the movement of the sensor main body 5 along the wall surface, the ceiling surface, the floor surface, or the like with the light receiving element of the sensor main body 5 facing the wall surface, the ceiling surface, the floor surface, or the like. For example, the sensor body 5 is provided with a handle. If the sensor body 5 itself has a size and shape that can be easily gripped with both hands or one hand, it is of course possible to omit this gripping portion. FIG. 1 shows a sensor body 5 of a type in which the grip portion is omitted.

The power supply device is a device for supplying DC power to the sensor main body 5, and is configured to convert AC power obtained from a commercial power source (not shown) into DC power and supply it to the sensor main body 5. That is, this power supply device is configured to include an AC / DC converter.

The interface cable 6 is a cable for supplying the image data output from the sensor main body 5 to the display device 4. The image data output from the sensor body 5 is input to the display device 4 via the interface cable 6.

The display device 4 is a device for displaying an image showing a transmitted X-ray dose from the image data output from the sensor main body 5, and as the display device 4, a portable display device, specifically, an image is displayed. A personal computer (for example, a laptop computer) or a personal digital assistant (for example, a tablet-type terminal device) having a display unit for displaying is used.

In this embodiment, a laptop computer is used as the display device 4. This laptop computer is provided with an image input / output board for displaying image data on a display unit composed of a liquid crystal panel or the like, and the image data supplied via the interface cable 6 is this image. It is displayed on the display via the input / output board. In this display, for example, an image of shades corresponding to the transmitted X-ray dose (for example, an image in which a portion having a large transmitted X-dose is light and a portion having a small transmitted X-dose is displayed dark) is displayed.

Next, the procedure of the X-ray leakage inspection using the X-ray leakage inspection system 1 configured in this way will be described with reference to FIGS. 2 and 3.

The X-ray leakage inspection according to the present invention is carried out in a room (including a corridor and upper and lower floors) around the room where the X-ray shielding work has been performed. FIG. 2 illustrates a case where an X-ray leakage inspection is performed in a room B adjacent to the X-ray clinic A where the X-ray shielding work is performed. In this case, a wall separating the X-ray clinic A and the adjacent room B is shown. An X-ray leak inspection is performed on W.

In the X-ray leakage inspection, first, the X-ray generator 2 is arranged in the X-ray clinic A. The X-ray generator 2 is arranged, for example, near the center of the X-ray clinic A or at a position where a medical device that generates X-rays is scheduled to be arranged, and a phantom is arranged to start X-ray irradiation. As a result, the entire room of the X-ray clinic A, such as the walls, floor, and ceiling in the X-ray clinic A, is irradiated with X-rays (including scattered X-rays) as shown by the chain line in FIG.

Then, in the adjacent room B where the X-ray leakage inspection is performed while performing the X-ray irradiation in the X-ray clinic A, the X-ray generator 2 and the radiation shielding material (wall W on which the X-ray shielding work is performed) are sandwiched. The surface on the opposite side (that is, the surface on the X-ray clinic A side) is set as the inspection surface We, and the inspection surface We is scanned while moving the line sensor camera 3 with respect to the inspection surface We.

Specifically, in scanning the inspection surface We, the operator inspects the sensor body 5 with the sensor body 5 of the line sensor camera 3 grasped and the light receiving element of the sensor body 5 facing the inspection surface We. This is done by moving along the surface We.

FIG. 3 shows an example of this scanning procedure. For example, as shown in FIG. 3A, the sensor main body 5 is moved in the vertical (vertical) direction (from the upper end to the lower end of the inspection surface We in the illustrated example) with respect to the inspection surface We to perform a vertical row of scanning. .. Then, when the scanning of this vertical row is completed, the user moves to the next row and scans in the vertical direction again. After that, by repeating this procedure, the entire surface of the inspection surface We is scanned by the line sensor camera 3. That is, scanning is performed in the vertical direction in order from the right end or the left end of the inspection surface We to scan the entire surface of the inspection surface We.

FIG. 3B shows a case where this scanning is performed in the left-right (horizontal) direction (in the illustrated example, from the right end to the left end of the inspection surface We). That is, by moving the sensor body 5 in the left-right direction (from the right end to the left end of the inspection surface We in the illustrated example) and scanning in a horizontal row, it is possible to scan the entire surface of the inspection surface We.

When the inspection surface We is scanned by the line sensor camera 3 in this way, the image data of the X-rays (X-rays transmitted through the wall W) received by the light receiving element during the scanning is displayed from the sensor body 5. It is input to the device 4, and an image corresponding to the transmitted X-ray dose is displayed on the display device 4. That is, in the present embodiment, an image of shades corresponding to the transmitted X-ray dose is displayed on the display unit of the display device 4.

The image displayed on the display device 4 according to the transmitted X-ray dose is configured to sequentially display the image data acquired by the display device 4 side as the line sensor camera 3 scans up and down or left and right. When all the vertical or horizontal scanning is completed, an image of the transmitted X-ray dose on the entire surface of the inspection surface We is displayed on the display unit. It should be noted that this display can be changed to a display with a limited range, such as displaying only one column of the scanned top, bottom, left and right.

As described above, according to the X-ray leakage inspection according to the present invention, there are construction defects such as holes and joint defects (locations through which X-rays pass) in the X-ray shielding material arranged inside the wall W serving as the inspection surface We. If there is, the X-ray transmission portion is visually confirmed on the display unit of the display device 4, so that the worker can easily confirm whether or not there is a defective portion in the X-ray shielding work. ..

Moreover, in the present invention, since the X-ray leakage inspection is performed by moving the line sensor camera 3 up and down or left and right along the inspection surface We, a certain width (line sensor camera) is obtained by scanning a row of up and down or left and right. It is possible to inspect the surface having the sensing width) for the presence or absence of X-ray leakage without omission.

Further, in the X-ray leakage inspection according to the present invention, the presence or absence of X-ray transmission can be confirmed by an image (in the present embodiment, an image of shades according to the transmitted X-ray dose), so even a small amount of X-ray transmission can be used as an image. It can be easily found and confirmed. Therefore, even if there is a very small hole in the X-ray shielding material, it can be easily and reliably found, while the X-ray leakage inspection can be performed with a small dose of X-rays generated by the X-ray generator 2. can. In particular, since the output dose of the X-ray generator 2 can be reduced, the X-ray leakage inspection can be performed at a dose that generally has almost no effect on the human body as the output dose of the X-ray generator 2, and the workers during the inspection It is possible to avoid exposure to people in the rooms around the X-ray clinic.

Embodiment 2
Next, a second embodiment of the present invention will be described.
In this second embodiment, the line sensor camera 3 has a transport table (transport means) (not shown) capable of moving the sensing region of the line sensor camera 3 up and down (vertical direction) and / or left and right (horizontal direction). ) Is fixed and used.

For example, as the carrier, a carriage provided with an elevating means (not shown) for elevating and lowering the line sensor camera 3 can be used. In this case, the line sensor camera 3 can be moved left and right with respect to the inspection surface We by moving the carriage in the horizontal direction, and the line sensor camera 3 can be moved up and down by moving the elevating means up and down. can.

As a result, the worker can scan the inspection surface We more easily and reliably without omission as compared with the case where the line sensor camera 3 is gripped and scanned.

It should be noted that the above-described embodiment merely indicates a preferred embodiment of the present invention, and the present invention is not limited to these, and various design changes can be made within the scope of the present invention.

For example, in the above-described embodiment, the case where the present invention is applied to the leakage inspection of X-rays is shown, but the present invention can also be applied to the leakage inspection of radiation (for example, gamma rays) other than X-rays. That is, in the gamma ray leakage inspection, the gamma ray leakage inspection can be performed by using the gamma ray generation source as the radiation generator and by using the line sensor camera 3 capable of sensing the gamma ray.

Further, in the above-described embodiment, the case where the X-ray leakage inspection is performed in the room B adjacent to the X-ray clinic A is shown, but the X-ray leakage inspection is also performed in the room on the upper floor or the lower floor of the X-ray clinic A. Can be done. That is, when performing an X-ray leakage inspection on the upper floor of the X-ray clinic A, scanning is performed by the line sensor camera 3 with the floor surface on the upper floor as the inspection surface We. Further, when performing an X-ray leakage inspection on the lower floor of the X-ray clinic A, scanning is performed by the line sensor camera 3 with the ceiling surface of the lower floor as the inspection surface We. Further, the line sensor camera 3 also scans the fitting surface on the opposite side of the fitting such as the door.

Further, in the above-described embodiment, in the X-ray leakage inspection, the case where the entire surface of the inspection surface We is scanned by the line sensor camera 3 is shown, but a part (predetermined range) of the inspection surface We is inspected. It is also possible to do. That is, in this case, the line sensor camera 3 scans only the portion where the X-ray leakage inspection is performed, and the transmitted X-ray image in the predetermined range is displayed on the display device, thereby limiting the partial X-ray. Line leakage inspection can be carried out.

Further, in the above-described embodiment, the case where an image of shades corresponding to the transmitted X dose is used as the image of the transmitted X dose to be displayed on the display device 4, but the color to be displayed is changed according to the transmitted X dose. Of course, it is also possible to adopt other display modes such as.

Further, in the above-described embodiment, the case where the X-ray leakage inspection is performed using one line sensor camera 3, but the X-ray leakage inspection is performed using a plurality of line sensor cameras 3, 3, ... It is also possible. That is, in this case, the interface cables 6, 6, ... Of the line sensor cameras 3, 3, ... Are connected to the display device 4, and there is a gap (sensing leakage) in the sensing region between the line sensor cameras 3, 3, .... With the line sensor cameras 3 arranged side by side in a row so as not to occur, scanning in the vertical or horizontal direction is performed on the inspection surface We. As a result, the X-ray leakage inspection can be performed more efficiently than the case where the inspection is performed by one line sensor camera 3.

1 X-ray leak inspection system (radiation leak inspection system)
2 X-ray generator (radiation generator)
3 Line sensor Camera 4 Display device 5 Sensor body 6 Interface cable W X-ray shielding work wall We inspection surface

Claims (1)

A radiation generator that generates radiation for inspection is placed in the room where radiation shielding work has been performed.
The surface on the opposite side of the radiation generator and the radiation shielding material is used as an inspection surface, and the inspection surface is scanned while moving the line sensor camera with respect to this inspection surface.
Radiation leakage for implementing a radiation leakage inspection method for displaying the transmitted radiation image of the inspection surface on the display device so that the position of the defective portion of the radiation shielding work on the inspection surface can be visually confirmed on the display device. It ’s an inspection system,
A portable radiation generator, a portable line sensor camera, and a display device that displays a transmitted radiation image on the entire surface of the inspection surface or a predetermined range based on the transmitted radiation data taken by the line sensor camera. ,
The line sensor camera is a radiation leakage inspection system characterized by having a grip portion that can be held by one hand.

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