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People's Republic of China (PRC) national standard medical X-ray health protection regulations (GBW-2 -80)

Effective timeliness

Promulgated by the Ministry of Health

Date of promulgation: 80 1024

Implementation date: 80 1024

valid period

Reference number

Name: People's Republic of China (PRC) National Standard Medical X-ray Health Protection Regulations (GBW-2 -80)

General rules of inscription

Article 1 These Provisions are formulated in order to strengthen the health protection management of medical X-ray work and ensure the safety of radiation workers, patients receiving treatment and residents.

Article 2 These Provisions shall apply to the production and use of medical therapeutic X-ray machines.

Article 3 The maximum allowable dose equivalent of occupational exposure of radiation workers and the limited dose equivalent of workers and residents in the vicinity of radiation workplaces shall be controlled in accordance with the requirements of relevant national radiation protection laws and regulations.

Article 4 Local radiation health protection departments shall be responsible for supervising the implementation of these Provisions. The first part is the health protection standard of medical X-ray machine.

Chapter I Technical Requirements

Article 5 The leakage rays of the X-ray tube head assembly shall not exceed the following table: (See the following table)

Article 6 A replaceable filter plate must be provided, and the specifications shall be marked on the filter plate. The X-ray machine for deep treatment must have an interlocking device, which can only be irradiated after the filter plate is inserted. -X-ray tube head assembly leakage limit ||| X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit | X-ray tube head assembly leakage limit-the voltage of the lamp is 50 ~ 100 | 0. 1 LUN/hour (. -the tube voltage is lower than 50 |-| 0. 1 LUN/hour (2.58×|| kV (peak value) |||| 0.00001coulomb/kg) |-.

Article 7 After the X-ray tube is connected with voltage, the exposure rate of the useful beam should quickly reach the specified value, so as to ensure that the deviation between the exposure accepted by the patient's treatment site and the calculated value (the product of the predetermined exposure time and the normal exposure rate) is not more than 5%. Otherwise, an electric shutter must be installed in the window of the X-ray machine and used in conjunction with the automatic timer. The protective thickness of shutters should not be less than 10 half-value layer.

Article 8 The exposure rate of X-rays passing through the light collecting tube shall not be greater than 5% of the exposure rate of useful beams at the distance from the focus 1 m..

Article 9 In any treatment position, the focus of the X-ray tube and the center of the fixed diaphragm should be on the same straight line with the central axis of the light collecting tube. The asymmetry of useful beam irradiance in irradiation field is less than 5%.

Article 10: The console must be equipped with corresponding devices to display: (1) the on-off of the X-ray tube voltage; (2) voltage and current of X-ray tube; (3) irradiation time; (4) the material and thickness of the filter plate; (5) Opening and closing of the shutter.

Article 1 1 It is necessary to install an integral dosimeter to monitor the useful wire harness and interlock with the automatic timer.

Article 12 In the parts of X-ray machine, the X-ray radiation level emitted by electronic tubes other than X-ray tubes shall not exceed 20 mJoule/hour (5. 16× 0.0000 1 coulomb/kg) at a distance of 5 cm from the equipment casing.

Article 13 The X-ray tube must be firmly installed, and the tube head assembly should be able to be locked in any required position.

Article 14 The X-ray machine used for surface treatment must be equipped with a manually controllable device for displaying irradiation on the shell of the tube head assembly, and a protective cap with a protective thickness greater than 0.5 mm lead equivalent.

Article 15 The product specification shall indicate the protective performance of the X-ray machine. On the shell of the tube head assembly, the focus position and inherent filtration shall be marked. The distance from the focal point to its exit surface and the irradiation field area on the exit surface should be marked on the light collector.

Chapter II Inspection Methods

Article 16 The total uncertainty of useful harness measurement should be less than 5%, and the total uncertainty of protection monitoring should be less than 30%. Open the shutter, insert the zero filter plate, and cover the socket of the light collector with not less than 10 layer of half-value lead. It is carried out under the conditions of the maximum working tube voltage of the X-ray machine and the maximum working tube current corresponding to this voltage. Leakage rays at a distance of 5 cm from the surface of the nozzle assembly shall be measured on the average of 10 cm2. The leakage rays from the focal point 1 m shall be measured on the average 100 cm2.

Article 17 X-ray tube head assembly test: Open the shutter and measure the average exposure of any four points outside the boundary of the irradiation field of 65438±0cm on the exit surface of the light collector under the highest voltage and filtering conditions listed in the table below. And compared with the exposure rate of the center of the irradiation field at the distance of 65438 0 meters from the focus. The spare collector tubes of the X-ray machine should be tested one by one. When measuring, there should be no scatterer within 2 meters from the focus in the exit direction.

Article 18 The test of the transmittance of the collector tube to the useful wire harness:-Maximum voltage (KV, |100 |150 | 200 | 250 | 300 | 400 |||| peak value) ||||||||-.

Article 19 Testing of asymmetry of useful beam: For the standby light collector of X-ray machine, the exposure rate of four points 2 cm away from the adjacent boundary in the corresponding irradiation field should be tested one by one, and the asymmetry of irradiation field should be measured by the deviation of each point from the average value. When measuring, there should be no scatterer within 2 meters from the focus in the direction of the air outlet.

Chapter III Acceptance Rules

Article 20 Whether the protective performance of the X-ray machine meets the requirements of this standard shall be inspected by the technical inspection department of the production unit, and the relevant departments shall not accept it until it is qualified.

Article 21 The type test (testing all items specified in this standard) shall be carried out under the following circumstances: (1) Before the new product is put into production; (2) products produced continuously at least once a year; (three) put into production at intervals of more than one year; (4) When the design, technology or materials change. (1) and (4) Type tests shall be conducted together with the local radiation protection department. Type test results should be sent to the local radiation health protection department for the record. Part II Health Protection Rules for Medical X-rays Chapter IV Protection Facilities

Twenty-second treatment room settings must fully consider the safety of the surrounding environment. The intensive treatment room must be separated from the control room. The treatment room should have sufficient use area, generally not less than 30 square meters. Do not pile up sundries indoors.

Article 23 The wall in the direction of useful beam projection in the treatment room should be designed according to the requirements of original ray shielding, and other directions can be designed according to the requirements of leakage ray and scattered ray shielding. In the treatment room of X-ray machine for deep treatment below 250 kV, the wall protection thickness in the projection direction of useless beam is 2 mm lead equivalent.

Twenty-fourth treatment room windows, must be set up reasonably. The observation window can be set on the wall in the direction of non-useful beam projection, which has the shielding and protection function of the same side wall.

Article 25 Work indicators and interlocking devices must be installed outside the treatment room. Irradiation can only be performed after the door is closed.

Chapter V Operating Rules

Twenty-sixth radiotherapy workers must receive training in radiation health protection, master the knowledge of radiation health protection, strictly grasp the indications of X-ray therapy, and use X-ray therapy correctly and reasonably.

Twenty-seventh X-ray machine operators must strictly abide by the operating rules. Regularly check the performance of X-ray machine and protective equipment before use, find problems and handle them properly.

Twenty-eighth according to the specific situation of patients' treatment, we should carefully determine the treatment plan and check it in advance. Pay attention to choose the appropriate irradiation mode and irradiation conditions (including X-ray tube working voltage, current, filtration conditions, focal distance, irradiation field and irradiation time, etc.). ), and carefully positioning, so that the radiation dose of the patient's treatment site is controlled at the minimum required for clinical treatment, and unnecessary radiation is reduced.

Twenty-ninth in the process of radiotherapy, X-ray machine operators must always monitor the console and patients, and eliminate all kinds of accidents in time.

Thirtieth X-ray irradiation depth treatment, in addition to patients receiving treatment, there should be no other personnel in the treatment room.

Thirty-first shallow treatment X-ray machine operators must use local shielding or remote protection. When using an X-ray tube with the highest voltage not exceeding 50 kV in clinic, the staff must wear protective gloves and aprons with lead equivalent not less than 0.25 mm Only the staff with equipment can control the electrification of the X-ray tube. The third part is medical X-ray health protection management.

Chapter VI Management Measures

Thirty-second local radiation health protection departments should strengthen the health protection management of the production and use of medical therapeutic X-ray machines. Registration system should be established for the use of medical therapeutic X-ray machines.

Article 33 All newly built, expanded and rebuilt X-ray treatment rooms must meet the requirements of site selection and building protection in these Provisions.

Thirty-fourth architectural design should be reviewed by the local radiation health protection department in advance. Before it is put into use, it should be checked by the health protection department before it can be used.

Thirty-fifth users should establish technical files of X-ray machines and protective facilities, and record and file maintenance information in time.

Article 36 After installation, the X-ray machine must be calibrated for X-ray output, line quality, uniformity and stability of the wire harness before it can be put into use, and it shall be tested regularly during use. Usually, the X-ray output is tested at least once a month.

Thirty-seventh users should set up full-time (part-time) personnel to be responsible for the radiation health protection work of their own units.

Article 38 Radiation workers receiving medical X-ray irradiation shall have personal dose and health records. Files should be transferred with the staff, and the original unit should keep its copy.

Article 39 Personnel engaged in medical X-ray work must undergo health examination, and those who are unwell are not allowed to participate in radiotherapy. Regular physical examination after work.

Fortieth whoever finds that radiotherapy workers have no indications should take necessary measures in time.