GB 15208.5-2018Micro-dose X-ray security inspection systems - Part 5: Backscatter object security inspection systems (English PDF)

3.1 Backscatter X-ray

Scattered X-rays greater than 90° with respect to incident X-rays.

3.2 Micro-dose X-ray backscatter article security inspection equipment

A backscattered microdose X-ray safety inspection device for inspecting articles.

3.3 Mobile backscatter X-ray safety inspection equipment

Mobile X-ray generating device and detector for backscattering X-ray imaging of backscattered articles device.

3.4 Fixed backscatter X-ray safety inspection equipment

The X-ray generating device does not move, and the back-scattered article micro-dose of the object to be examined is realized by back-scattering X-ray imaging through the inspection area X-ray safety inspection equipment.

3.5 Open backscatter X-ray security inspection equipment

Radiation protection devices for shielding, leaking rays, etc. generated during the inspection process are not installed, and it is necessary to delineate the supervision area or place it in compliance.

Radiation protection requires a backscattered item of micro-dose X-ray safety inspection equipment.

3.6 Closed backscatter X-ray safety inspection equipment

Micro-dose X-rays of backscattered articles with radiation protection devices for shielding scattering, leaking rays, etc. generated during inspection Safety inspection equipment.

3.7 Backscattering penetration

The ability of the device to resolve organic matter behind a certain thickness of the steel plate.

Note: It is expressed by the thickness (mm) of the steel plate.

3.8 Backscatter spatial resolution

The ability of the device to distinguish pairs of polyethylene wires in an air background.

Note: Indicated by the line width (mm) of the pair.

3.9 Backscatter line resolution

The device distinguishes the ability of a single polyethylene rod in an air background.

Note: Indicated by the diameter of the rod (mm).

3.10 Backscatter line detection force

The device's ability to resolve a single solid copper wire in the context of a strong scatterer.

Note: Indicated by the nominal diameter of the wire (mm).

3.11 Backscatter contrast sensitivity

The ability of the device to resolve thin organic matter of the same material in the context of thick organic scattering.

Backscatter contrast sensitivity = Thin organic thickness Total thickness of organic absorbent × 100% (1)

5.1 Overview

A device with multiple scattering viewing angles, the performance index of any viewing angle should meet the requirements of 5.2; with multiple scattering inspection channels Equipment, the performance indicators of any of its channels should meet the requirements of 5.2. Overall performance of a device with multiple scattering viewing angles or multiple scattering channels The test results of the viewing angle or channel marked with the worst performance index shall prevail. Xray generators should be maintained when performing tests 5.2.1~5.2.5 The tube voltage, tube current and other parameters are unchanged.

When applied to vehicle-borne equipment, this chapter only targets the key components related to X-ray emission, acquisition and imaging. Performance is required.

5.2 Performance Specifications

5.2.1 Backscattering penetration

See the requirements for the thickness of the steel plate. See Table 1.

5.2.2 Backscattering spatial resolution

Should be able to distinguish the requirements of polyethylene line line width, see Table 1.

5.2.3 Backscattering line resolution

Should be able to distinguish the requirements of the diameter of a single polyethylene rod, see Table 1.

5.2.4 Backscatter line detection force

Should be able to distinguish the requirements of a single solid copper wire diameter, see Table 1.

5.2.5 Backscattering contrast sensitivity

Should meet the requirements of the percentage of polyethylene test card resolution, see Table 1.

5.2.6 Inspection speed

Should meet the requirements of inspection speed, see Table 1.

5.3 Radiation and environmental safety indicators

5.3.1 Single dose check

Should comply with the provisions of 5.2.1 of GB 15208.1-2018.

5.3.2 Peripheral dose equivalent rate

Should comply with the provisions of 5.2.2 of GB 15208.1-2018.

5.3.3 Equipment noise

Should comply with the provisions of 5.2.3 of GB 15208.1-2018.

5.4 Operating environment

Should comply with the provisions of 5.3 of GB 15208.1-2018.

5.5 Security performance

It shall comply with the provisions of 5.4 of GB 15208.1-2018 [except for the provisions of 5.4.1 g].

5.6 Mechanical structure

Should comply with the provisions of 5.5 of GB 15208.1-2018.

5.7 Electromagnetic compatibility

Should comply with the provisions of 5.6 of GB 15208.1-2018.

5.8 Anti-shock

Should comply with the provisions of 5.7 of GB 15208.1-2018.

5.9 Anti-mechanical danger

Should comply with the provisions of 5.8 of GB 15208.1-2018.

5.10 Preventing the spread of flame

Should comply with the provisions of 5.9 of GB 15208.1-2018.

5.11 Temperature limits and heat resistance

Should comply with the provisions of 5.10 of GB 15208.1-2018.

5.12 Environmental adaptability

Should comply with the provisions of 5.11 of GB 15208.1-2018.

5.13 Functional requirements

Should comply with the provisions of 5.12 of GB 15208.1-2018.

6.1 Environmental requirements

Should comply with the provisions of 6.1 of GB 15208.1-2018.

6.2 Main instruments and tools for testing

Should comply with the provisions of 6.2 of GB 15208.1-2018.

Test body: see Appendix A. Scatter: see Appendix B.

6.3 Performance Indicator Test

6.3.1 Overview

The placement and orientation of the test body depends on the relative position of the X-ray generating device and the detector. The test body plane should be vertical In the X-ray emission direction, the placement position can be reasonably selected within the nominal inspection area of the device to obtain the best test body image. In addition, I use image processing to get the best evaluation results. The test results should be recorded in the format of Appendix C.

6.3.2 Backscatter penetration test

The test steps are as follows.

a) The additional test steel plate is located on the side of the near X-ray generator, and the polyethylene test card arrow is located away from the X-ray generator one side.

b) The arrow of the test card can be oriented in any direction.

c) Start and complete the scan, visually measure the X-ray image of the test body on the display, and observe whether the polyethylene test card arrow can be correctly distinguished. The shape and position of the head.

d) Change the thickness of the additional test steel plate and repeat step c) until the shape and position of the arrow after the thickest additional test steel plate is positive Identify it.

e) Record the total thickness of the test steel plate (the thickness of the test card fixed steel plate plus the thickness of the additional test steel plate). Whether the judgment result is consistent with the requirements of 5.2.1.

6.3.3 Backscattering spatial resolution test

The test bodies are placed horizontally and vertically, respectively, and the scan is initiated and visualized to visually measure the X-ray image of the test body on the display. The result of the judgment is Does not meet the requirements of 5.2.2.

Note: If all four test lines of the horizontal and vertical pairs are completely separated, the device can be considered to be able to resolve the pair.

6.3.4 Backscattering line resolution test

The test bodies are placed horizontally and vertically, respectively, and the scan is initiated and visualized to visually measure the X-ray image of the test body on the display. The result of the judgment is Does not meet the requirements of 5.2.3.

Note: If the complete 3 polyethylene rods are visible both horizontally and vertically, the device can be considered to be able to distinguish polyethylene rods of this diameter.

6.3.5 Backscatter line detection force test

The test body wire is located on the side of the X-ray generating device, starts and completes the scanning, and visually measures the X-ray image of the test body on the display. Determine whether the result meets the requirements of 5.2.4.

Note: If you can see the complete wire, you can think that the device can distinguish the wire.

6.3.6 Backscattering contrast sensitivity test

The test steps are as follows.

a) The additional test card is located on the side of the X-ray generator, and the additional polyethylene backing plate is located on the fixed polyethylene back plate away from X-rays, one side of the device.

b) Start and complete the scan, visually measure the X-ray image of the test body on the display, and observe whether the additional test card arrow can be correctly distinguished. Shape and location.

c) Change the thickness of the additional test card and the thickness of the additional polyethylene backing, repeat step b) until the thinnest additional test card arrow The shape and position of the head are correctly identified.

d) Record the thickness of the thinnest additional test card and the thickness of the additional polyethylene backing. Determine whether the result meets the requirements of 5.2.5.

e) Calculate the contrast sensitivity according to equation (2). Backscatter contrast sensitivity = Polyethylene test card total thickness (mm)

Additional polyethylene backing plate total thickness (mm) Fixed polyethylene backing plate thickness (mm) × 100% (2)

6.3.7 Checking the speed test

The test method is as follows.

a) For stationary equipment, the fixed equipment is in normal working condition, and the test equipment or test target of the fixed equipment is tested.

Calculate the conveying speed per unit time travel. Determine whether the result meets the requirements of 5.2.6.

b) For the mobile device, make the mobile device in normal working condition, test the unit time travel of the mobile device, calculate the shift Dynamic speed. Determine whether the result meets the requirements of 5.2.6.

6.4 Radiation and environmental indicators test

6.4.1 Single dose test

Test the equipment according to the test method specified in 6.3.1 of GB 15208.1-2018, and determine whether the result meets the requirements of 5.3.1.

6.4.2 Peripheral Equivalent Rate Test

The test method is as follows.

a) For closed equipment, place the scatterer with the same number of ray bundles (see Appendix B) in the inspection channel The horizontal center of the surface, each scatterer is illuminated by a beam of radiation, and the scatterer's 400mm × 400mm plane Parallel to the beam exit direction. The equipment shall be tested according to the test method specified in 6.3.2 of GB 15208.1-2018. determination Whether the result meets the requirements of 5.3.2.

b) For open equipment, test in accordance with Appendix D. Test method According to D.1, test the workplace according to D.2. Judge Whether the result meets the requirements of 5.3.2.

6.4.3 Equipment noise test

The test method is as follows.

a) For line pack equipment, the noise level should be measured with a sound level meter at any point 1 m away from the equipment enclosure. Whether the result of the judgment is The requirements of 5.3.3.

b) For container and vehicle-type equipment or vehicles-based equipment, noise should be measured with a sound level meter at the location of the staff member value. Determine whether the result meets the requirements of 5.3.3.

6.5 Power supply range test

The equipment shall be tested according to the test method specified in 6.4 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.4.

6.6 Safety function test

The equipment shall be tested according to the test method specified in 6.5 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.5.

6.7 Mechanical structure test

The equipment shall be tested according to the test method specified in 6.6 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.6.

6.8 Electromagnetic compatibility test

The equipment shall be tested according to the test method specified in 6.7 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.7.

6.9 Anti-shock test

The equipment shall be tested according to the test method specified in 6.8 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.8.

6.10 Anti-mechanical danger test

The equipment shall be tested according to the test method specified in 6.9 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.9.

6.11 Prevention of flame spread test

The equipment shall be tested according to the test method specified in 6.10 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.10.

6.12 Temperature limits and heat resistance test

The equipment shall be tested according to the test method specified in 6.11 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.11.

6.13 Environmental Adaptability Test

The equipment shall be tested according to the test method specified in 6.12 of GB 15208.1-2018. Determine whether the result meets the requirements of 5.12.

6.14 Functional Requirements Test

Perform the operation test according to the manufacturer's product instructions. Determine whether the result meets the requirements of 5.13.

Only 5.12.1a), 5.12.2 and 5.12.5 in GB 15208.1-2018 are required.

7.1 Inspection classification

Should comply with the provisions of 7.1 of GB 15208.1-2018.

7.2 Type inspection

Should comply with the provisions of 7.2 of GB 15208.1-2018.

7.3 Factory inspection

Should comply with the provisions of 7.3 of GB 15208.1-2018.

7.4 Inspection items

The inspection items are shown in Table 2.

7.5 Evaluation of test images during type inspection

Should comply with the provisions of 7.5 of GB 15208.1-2018.

7.6 Inspection

Should comply with the provisions of 7.6 of GB 15208.1-2018.

7.7 Decision rules

Should comply with the provisions of 7.7 of GB 15208.1-2018.

A.1 Backscattering penetration test body

The backscatter penetrating test body consists of an arrow-shaped polyethylene test card, a test card-mounted steel plate (including a bracket), and a set of additional tests of different thicknesses.

Steel plate and connector. A 100 mm thick polyethylene test card is centered on the test plate to hold the steel plate. Test card fixed steel plate thickness The degree is 2.0mm. The shape of the backscattering penetration test body is shown in Figure A.1~Fig. A.3; the overall dimensions are shown in Figure A.4. See the dimensions of the fixed steel plate and the bracket.

Figure A.5; arrow-shaped polyethylene test card dimensions are shown in Figure A.6; test body additional steel plate dimensions are shown in Figure A.7; additional test steel plate thickness specifications see Table A.1. Figure A.1 Backscattering penetration test body shape perspective view Figure A.2 Backscattering penetration test body profile main view Description.

1---2mm thick test card fixed steel plate and bracket, the material is 45 carbon steel plate;

2---polyethylene arrow-shaped test card, made of 100mm thick polyethylene plate, density of 0.95g/cm³ ± 0.05g/cm³; 3---polyethylene test card fixing screw; 4---Additional test steel plate fixing bolts and nuts;

5---Additional test steel plates, all of which are 45 carbon steel plates. Figure A.3 Backscattering penetration test body top view

The unit is mm Figure A.4 Overall Dimensional Drawing of Backscattering Penetration Test Body The unit is mm Figure A.5 Backscattering penetration test body fixed steel plate and bracket size chart The unit is mm Figure A.6 Backscattering penetration test body arrow-shaped polyethylene test card size chart The unit is mm Figure A.7 Backscattering penetration test body additional steel plate size drawing Table A.1 Additional test steel plate thickness specifications in millimeters

A.2 Backscattering spatial resolution test body

The backscattering spatial resolution test body consists of 11 pairs of test cards and fixing brackets made of different specifications and polyethylene plates. Backscatter The spatial resolution test body shape is shown in Figure A.8~Figure A.10; the overall dimensions are shown in Figure A.11; the fixed bracket dimensions are shown in Figure A.12;

Dimensions are shown in Figure A.13; wire pair test card size specifications are shown in Table A.2. Figure A.8 Backscattering spatial resolution test body outline stereogram Description: 1~11---pair test card, made of polyethylene plate, density is 0.95g/cm³±0.05g/cm³;

12 --- Test card fixing bracket, the material is aluminum. Figure A.9 Backscattering spatial resolution test body profile main view Figure A.10 Backscattering spatial resolution test body profile top view

The unit is mm Figure A.11 Backscattering spatial resolution test body overall size The unit is mm Figure A.12 Backscattering spatial resolution test body fixing bracket overall size drawing The unit is mm Figure A.13 Backscattering spatial resolution test body test card size chart Table A.2 Wire pair test card size specifications in millimeters

A.3 Backscattering line resolution test body

The backscatter line resolution test body consists of 16 sets of polyethylene rods of different diameters and a frame. See the backscatter line resolution test body shape Figure A.14~Figure A.16; overall dimensions are shown in Figure A.17; fixed bracket dimensions are shown in Figure A.18; polyethylene test rod dimensions are shown in Figure A.19; The bar size specifications are shown in Table A.3. Figure A.14 Backscattered line resolution test body shape perspective view Description: 1~16---polyethylene test rod, density is 0.95g/cm³±0.05g/cm³;

17 --- polyethylene test rod fixed frame and bracket, the material is aluminum. Figure A.15 Backscattered line resolution test body profile main view Figure A.16 Backscattered line resolution test body profile top view

The unit is mm Figure A.17 Backscattered line resolution test body size The unit is mm Figure A.18 Backscattered line resolution test body bracket overall size drawing The unit is mm Figure A.19 Backscattered line resolution test body polyethylene test rod size chart […]