GBZ 175-2006 Standards for radiation protection of γ-ray industrial computed tomography
1 Scope
This standard specifies the protective performance of γ-ray industrial computed tomography (CT) equipment, the protective facilities of the test room and the radiation protection requirements for γ-ray industrial computed tomography equipment during use and maintenance.
This standard is applicable to γ-ray industrial computed tomography equipment with a sealed radioactive source activity greater than or equal to 4×1010 Bq and its scanning testing practice; it also applies to γ-ray industrial computed tomography equipment with a sealed radioactive source activity less than 4×1010 Bq and its scanning testing practice by reference.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions, of any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition applies.
GB 4075 Sealed radioactive sources - General requirements and classification
GB 11806 Regulations for the Safe Transport of Radioactive Material
GB 18871 Basic standards for protection against ionizing radiation and for the safety of radiation sources
GBZ 128 Specifications for individual monitoring of occupational external exposure
GBZ 132 Radiological protection standards for industrial gamma defect detecting
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1
γ-ray industrial computed tomography equipment
equipment for conducting tomographic imaging of workpieces by using γ rays, comprising of CT scanning device, data acquisition and processing system, operating consoles, etc., referred to as “industrial CT equipment” for short
3.2
container of radiation sources
special container used for storing and shielding sealed radioactive sources, as well as accurately geometrically positioning radioactive sources and limiting radiation beams
3.3
test room
special workshop at which the scanning devices of industrial CT equipment are placed and CT scanning of objects is performed
4 Requirements for radiation protection performance of industrial CT equipment
4.1 Safety requirements for radioactive sources
4.1.1 The classification and quality control methods for sealed radioactive sources of industrial CT equipment shall comply with the provisions of GB 4075. See Annex A for the grade performance requirements of sealed radioactive sources of industrial CT equipment.
4.1.2 The transportation of radioactive sources shall comply with GB 11806 and relevant safety protection requirements. During transportation, the γ-ray beams shall be in an OFF state and have a special locking device.
4.1.3 The replacement of radioactive sources shall comply with the relevant provisions of GBZ 132.
Contents
Foreword i
1 Scope
2 Normative References
3 Terms and Definitions
4 Requirements for radiation protection performance of industrial CT equipment
5 Requirements for radiation protection of industrial CT equipment workplaces
6 Requirements of radiation protection in operation of industrial CT equipment
7 Radiation protection monitoring and inspection
Annex A (Normative) Grade (performance) requirements for sealed radioactive sources for industrial CT equipment
Annex B (Normative) Radiation protection monitoring method of industrial CT equipment
Annex C (Normative) Categories and cycles of radiation protection monitoring and inspection of industrial CT equipment
