GB 15208.1-2018Micro-dose X-ray security inspection systems - Part 1: General technical requirements (English PDF)

3.1 Equivalent atomic number

Zeff An atomic number representing the theoretical element of a material property that has the same X-ray attenuation characteristics as this material.

3.2 Equivalent organic matter

A substance with an equivalent atomic number below 10.

3.3 Equivalent inorganic effective inorganic material

A substance with an equivalent atomic number higher than 18.

3.4 Equivalent mixture effective mixed material

A substance whose equivalent atomic number is between 10 and 18.

3.5 Wear impenetrable area

The intensity of X-ray penetration of the object to reach the X-ray detector is almost zero, and the device cannot recognize the basic structural features of the object under test. […]

3.6 Material uncertainty area

Although the ray can penetrate, it is impossible to identify the area of the material property of the object to be inspected.

3.7 Single dose

The subject undergoes an examination to absorb the absorbed kinetic energy of the air.

Note: The single-dose dose unit is Gy, 1Gy=1J/kg.

3.8 Peripheral dose equivalent rate

The quotient of dH *(10) and dt, where dH *(10) is the increment of the surrounding dose equivalent within the time interval dt.

Note: The International System of Units (SI) unit for the surrounding dose equivalent rate is [Watt] per second (Sv/s). The unit of the surrounding dose equivalent rate is [Watt] or its multiple Or the quotient of the score with the appropriate time unit (for example. mSv/h). [GB/T 4835.1-2012, definition 3.3]

3.9 Scatter

An object that scatters radiation to produce the worst radiation conditions.

3.10 X-ray security inspection equipment

X-ray intensity distribution or energy spectrum distribution is measured by the interaction of X-rays with the object to be inspected, and an X-ray image of the object to be inspected is generated.

An apparatus that recognizes the safety of the object to be inspected based on the information of the material to be inspected.

3.11 Micro-dose X-ray safety inspection equipment

A single inspection of X-ray safety inspection equipment with a dose less than or equal to 10 µGy.

3.12 Transmissive micro-dose X-ray safety inspection equipment

Generating an X-ray image of the object to be inspected or providing a detected pair by measuring an X-ray intensity distribution or an energy spectrum distribution passing through the object to be inspected

Like material information, a micro-dose X-ray safety inspection device that identifies the safety of the object to be inspected.

3.13 Backscatter micro-dose X-ray safety inspection equipment

Using the scattering effect of X-ray photons and matter interaction, collecting backscattered X-rays scattered by the object under test and generating a test Micro-dose X-ray safety inspection device for object images.

3.14 Single-energy spectrum micro-dose X-ray safety inspection equipment

Using X-ray interaction with the object to be inspected, measuring the intensity distribution of the X-ray and imaging the structural characteristics of the object to be inspected Micro-dose X-ray safety inspection equipment.

3.15 Multi-energy micro-dose X-ray security inspection system

According to the laws of different equivalent atomic numbers on the absorption characteristics of X-ray energy spectrum, the material properties of the object to be inspected are judged. A micro-dose X-ray safety inspection device that recognizes and images.

3.16 Control area

An area defined in a radiation workplace where special protective measures and safety measures are required or may be required, so that.

a) control normal exposure or prevent contamination expansion under normal operating conditions;

b) Prevent potential exposure or limit its extent. [GB 18871-2002, definition J5.5]

3.17 Supervised area

Anyone who has not been identified as a control area, usually does not need to take special protective measures and safety measures, but must constantly check his occupational exposure conditions What area. [GB 18871-2002, definition J5.6]

3.18 Open micro-dose X-ray safety 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 micro-dose X-ray safety inspection equipment at the location.

3.19 Closed micro-dose X-ray safety inspection equipment

Micro-dose X-ray safety inspection with radiation protection devices for shielding scattering, leaking rays, etc. generated during the inspection process device.

3.20 Safety interlocking device

A device that protects the X-ray equipment from working safely and prevents X-rays from being emitted under abnormal conditions. […]

3.21 Emergency stop switch

In an emergency, the components of the power supply of the X-ray generating device and the conveying device can be cut off immediately.

3.22 X-ray generating device

Generate and control a combination of all components of the X-ray emission.

Note: Usually consists of an X-ray tube, a high voltage generator, a controller, and a cooling system.

3.23 X-ray detector

A sensor that detects (measures) X-rays and converts X-ray intensities into electrical signals that can be processed.

3.24 Test body

A test object for testing and evaluating X-ray image performance indicators.

3.25 Test card

A test object used to test and evaluate an indicator of X-ray images.

5.1 Overview

For combined equipment (eg transmission, backscatter combination), all technical requirements of the respective technology type should be met.

5.2 Radiation and environmental safety indicators

5.2.1 Single dose check

A single inspection dose of a device with only one X-ray generating device should be less than or equal to 5 µGy, and there are multiple X-ray generating devices.

A single check dose should be less than or equal to 10µGy, a device with multiple inspection channels, and a single dose of any one of the channels Should meet the above requirements.

5.2.2 Peripheral dose equivalent rate

When the equipment is working normally, the enclosed equipment is at a distance of 0.1m from any accessible surface of the equipment (including the inlet and outlet of the equipment).

The volume equivalent rate should be less than or equal to 1µSv/h; open equipment needs to be delineated or placed in compliance with radiation protection requirements, outside the supervision area The surrounding dose equivalent rate should be less than or equal to 2.5 µSv/h; the surrounding dose equivalent rate of the worker position should be less than or equal to 0.5 µSv/h.

5.2.3 Equipment noise

The equipment noise should be less than or equal to 65dB (A) at any point 1m away from the outer surface of the equipment during normal operation.

5.3 Operating environment

5.3.1 Working environment conditions

Ambient temperature range. 5 ° C ~ 40 ° C. Relative humidity range. 5%~85%. Atmospheric pressure range. 70kPa~106kPa.

5.3.2 Power Adaptability

The power supply voltage shall be within 10%-15% of the nominal voltage and the nominal frequency ±3Hz, and the equipment shall be able to operate normally.

5.4 Security performance

5.4.1 Equipment Safety

Requirements are as follows.

a) The equipment should have obvious system operation and ray emission display devices (indicators);

b) The equipment should be equipped with an emergency stop switch at a location accessible to the operator. If an emergency occurs, the equipment X can be cut off immediately.

The power supply of the radiation generating device and the conveying device; the emergency stop switch should use a red switch with a yellow bottom;

c) The equipment shall be equipped with a power overcurrent protection device of appropriate rating to prevent overuse of internal components or other accidents. Current may cause a fire hazard;

d) The equipment shall be provided with a key switch and a secondary power start switch, and the key switch shall be able to clearly identify the "on" and "off" positions;

e) A safety protection interlock shall be fitted on the detachable radiation protection component of the X-ray emission area. Once the interlock is disconnected,

The power supply of the X-ray generating device of the device can be cut off immediately, and the X-ray should stop emitting immediately;

f) The equipment should have an operator identification function;

g) The equipment shall display the gray scale of the material uncertainty area and give obvious hints to the impervious area.

5.4.2 X-ray generating device safety

Requirements are as follows.

a) The X-ray generator shall be self-cooled within the equipment;

b) X-ray generators using external circulation cooling systems should have temperature or pressure control when the temperature of the coolant (oil or water) exceeds When the specified value is exceeded or the circulating pressure is lower than the specified value, the X-ray emission can be automatically stopped;

c) The X-ray generating device shall have an overvoltage and overcurrent protection function, which can automatically be used when its voltage or current exceeds the specified value of the product. Cutting off the high pressure;

d) The X-ray generating device shall have a protective grounding wire. The color of the grounding wire shall be yellow-green, and the grounding resistance shall not exceed 0.1 ohm.

5.5 Mechanical structure

Requirements are as follows. […]

5.5.1 Appearance section

Requirements are as follows.

a) The design and operation procedures of the equipment shall be in accordance with the basic requirements of ergonomics and shall be easy to operate and maintain;

b) The appearance of the equipment should be intact, the surface should be smooth and smooth, the color should be uniform, no obvious mechanical damage, no blistering damage to the coating, metal The parts shall be free from rust and the plastic parts shall be free from blistering and cracking;

c) Mark and write on the panel clearly.

5.5.2 Mechanical part

Requirements are as follows.

a) The equipment consists of parts and all parts, and should have sufficient strength and rigidity. All adjustment and control mechanisms should be installed correctly and operated. flexible;

b) The installation and disassembly of the outer cover should be convenient;

c) The frame shall have sufficient strength and rigidity to be free from deformation or damage during normal handling;

d) The equipment casters should have sufficient strength and rotational flexibility, and the connection with the equipment should be firm and reliable;

e) The degree of protection of the enclosure shall comply with the provisions of GB/T 4208-2017 and not less than the requirements of IP20.

5.6 Electromagnetic compatibility

5.6.1 Equipment Immunity

Electrostatic discharge, radio frequency electromagnetic field radiation, electrical fast transient bursts, surge (shock), and RF field induced conduction disturbances And 6 voltage immunity tests for voltage sag, short interruption and voltage change. The immunity performance of equipment working in industrial environment should be consistent.

The requirements for the limits specified in Tables 1, 2 and 4 of GB/T 17799.2-2003. Equipment for working in residential, commercial and light industrial environments The immunity performance shall comply with the requirements specified in Tables 1, 2 and 4 of GB/T 17799.1-2017.

5.6.2 Equipment launch

The radiated and conducted emission values of equipment operating in an industrial environment shall comply with the limits specified in Table 1 of GB/T 17799.4-2012.

The radiated and conducted emission values of equipment operating in residential, commercial and light industrial environments shall be in accordance with Table 1 of GB/T 17799.3-2012 The requirements for the specified limits.

5.7 Anti-shock

The equipment shall be protected against electric shock under normal conditions and single fault conditions, and the accessible parts of the equipment shall not be dangerously charged. Meet the requirements of Chapter 6 of GB 4793.1-2007.

5.8 Anti-mechanical danger

Operation under normal conditions or under single fault conditions shall not cause mechanical hazards and comply with the requirements of Chapter 7 of GB 4793.1-2007.

5.9 Preventing the spread of flame

Under normal conditions or under single fault conditions, the flame shall not spread to the outside of the equipment, in accordance with Chapter 9 of GB 4793.1-2007.

5.10 Temperature limits and heat resistance

The temperature limit and heat resistance of the equipment shall comply with the requirements of Chapter 10 of GB 4793.1-2007.

5.11 Environmental adaptability

5.11.1 Overview

The environmental adaptability of equipment and electrical components with independent functions meets the following requirements.

a) The equipment is a large-scale electromechanical product. When it is not suitable for environmental testing of the whole machine, it is allowed to press the electrical parts with independent functions separately. 5.11.2 and 5.11.5 shall be tested; the technical indicators of the whole machine or electrical component test shall meet the requirements of the equipment or components;

b) Electrical components with independent functions, after testing in 5.11.2 and 5.11.5, connect to the whole machine to test the whole machine, the equipment should be able to normal work;

c) After climatic and mechanical environmental tests, equipment should not show signs of corrosion and mechanical damage.

5.11.2 Climate and environmental adaptability

See Table 1 for requirements.

5.11.3 Resistance to mechanical shock and impact