GB/T 16149-1995 Specification for dose estimation of chronic radiation sickness caused by external exposure
Some standard content:
National Standard of the People's Republic of China
Specification for estimation of dose for chronlcradiation sickness from external exposure 1 Subject content and scope of application
GR/T 16149-1995
The standard stipulates: Basic principles and methods for dose estimation of chronic radiation sickness from external exposure. This standard is applicable to the dose estimation of patients with chronic radiation sickness from external exposure and persons to be diagnosed (hereinafter referred to as persons>, and is also extended to the dose estimation for radiation etiology diagnosis of patients with chronic radiation sickness from external exposure. 2 Terminology
2.1 Chronic radiation sickness from external exposure
refers to the external exposure of workers that exceeds the dose limit continuously or intermittently for a long period of time, reaching A systemic disease caused by a certain cumulative dose, characterized by damage to hematopoietic tissue and accompanied by changes in other systems. 2.2
irradiation intensity × is the quotient divided by dm, where is the total charge X of the same sign generated in the air when the photon is completely ionized in the air. The SI unit of irradiation is \℃kg1" as \k\, and its relationship with the original position of the irradiation is 1R-2.58×i0--c kg 1 (correct value),
In this standard, unless otherwise specified, the irradiation refers to the irradiation under the condition of no receptor in the air (receptor-free condition). The irradiation base under the condition of receptor (for example, the irradiation measured on the surface of the phantom or the irradiation measured by the personal dose meter of the personnel at the time) will be explained. 2.3 Red bone marrow
refers to the weighted average dose D of the residual and red bone marrow. , that is, I. =Em.D/M
Distributed in: human body 1 part of the red bone marrow, kg Chinese ten:,
), -1 part of the red bone marrow absorbent leather, Gy
The red bone mass of the whole body, kg.
......
2.4 Effective dose equivalent basis
In order to evaluate the total risk of random effects on the human body caused by the irradiated organs or tissues, radiation protection reduction introduced the effective dose, which is defined as
In the formula: Ht
Organ or tissue T dose equivalent:
Approved by the State Administration of Technical Supervision on December 15, 1995 WH
Implementation on July 1, 1996
GB/T 16149—1995
The risk of random effects of a unit dose to an organ or tissue is equal to the ratio of the risk of random effects due to a unit dose to an organ or tissue alone to the total risk of random effects due to a unit dose to the whole body. The units of H and H are both sievert (Sv), 1Sv=1 kg-1. 2.5 Particle Fluence
The particle fluence is the quotient of d divided by da, which is the number of particles per person with a radiation area of a. ..dw
Where is the particle fluence, m-1 (or m),
3 Dose Estimation Methods
3.1 In the dose-based evaluation of chronic radiation diseases caused by external radiation, the determination of the dose rate error of ionizing radiation on the renal function of personnel is used. Since the main feature of chronic radiation disease caused by external radiation is the damage to hematopoietic tissue, the delayed dose of the person should be given and used to evaluate the definite effect of ionizing radiation on the hematopoietic tissue of the person, and it can be used as the value for evaluating the total body dose of the person. In order to facilitate a more comprehensive dose assessment of the person, this standard also gives an effective and appropriate estimation method. 3.2 When the personal or workplace dose measurement data of the person are known, the following method is used to estimate the cumulative exposure or particle fluence.
3.2.1 If the personal dose monitoring data of the person are available, the cumulative exposure X monitored by the personal dose meter of the person, called the cumulative exposure X, is calculated according to the formula (5): ,-2
From the exposure space monitored by the personal dose meter during the period of inflammation work, C/k per person; the total time for Class 1 work is.%.
Equation (6) is obtained under the condition that the radiation source, protection conditions and the average radiation dose per unit time remain unchanged during the period.
3.2.2 If the dose monitoring data of the workplace where the personnel are located is L, and the workplace is free air exposure rate is , or the particle injection rate is , and the working time in the workplace is 1, then the cumulative radiation or particle injection in various workplaces can be obtained according to equation (6) and equation (7).
3.2.3 For medical diagnostic x-ray workers, if the number of people in each workplace (number of inspections) is W, the average noise time t for each inspection, and the average radiation dose rate at the operating position is , then the cumulative exposure X of the personnel in each workplace is obtained according to equation (8). EWe.x./k
Equation, K,-
! When working in this way, use protective equipment such as a gantry to reduce the amount of exposure. If protective equipment such as a skirt is not used, K;1.
3.3 For some people without dose measurement data, the exposure or particle injection dose can be estimated by the method described above. 3.3.1 For medical diagnostic X-ray workers, according to their workload, the capacity of the X-ray machine, the protective conditions of the factory time, and the use of the implant, select medical workers with similar positions from the survey data of the same medical diagnostic X-ray workers. 161491995
Diagnose the exhaustion of water under the working conditions, and estimate the exposure time under the working conditions (see Appendix 1). You can also use the above method (see Appendix G) to estimate the exposure time. 3.3.2 For personnel who are exposed to external radiation radioactive source, on the basis of confirming and verifying their contact with the source, the activity of the source should be checked one by one, according to the contact time, the protection of the center of the source, and the total exposure. If there is no record, the actual or simulated detection should be used to verify the exposure of the personnel who are exposed to the source. When there is no protection, the exposure in the operation should be expected, and the total exposure Address X, according to formula (9) and formula (10):
The irradiation rate constant of the fusion nuclide source for this operation (introduction to Table A1): F-
, double \m\ is the unit, with \ as the unit, when A, and, are used in 51 units, then X, is (, kg\; if A. and are used in special estimates, the unit of x. is R
3.3.3 The person who is exposed to the neutron source is only. The average fluence Φ at a distance of "cm" from the center of the neutron source is approximately calculated according to formula (11), A,
Where: one is the time of exposure to the neutron source, A.... The intensity of the neutron source
The neutron yield per becquerel, the neutron "amount for some nuclides neutron sources is given in the Yin record exchange. .... ( 11)
3.4 When the individual dose is only monitored by the cumulative exposure of the case or work place, the cumulative exposure of the person can be calculated based on the conversion cumulative data obtained by the phantom experiment or calculation under the exposure conditions similar to the exposure conditions (including the red bone marrow dose).
3.4.1 For the personnel exposed or exposed, when the cumulative dose of the total personal dose is known, the device dose (including the red bone marrow dose) and the effective dose can be calculated according to formula (12) and (13): D
HCurXe
The conversion coefficient between CiX and DI is:
C…X, and the conversion coefficient between them.
（12）
For the actual exposure to tea or for the line (and (z) recorded when B and B2 are given. 3.4.2 For people who are exposed to X or radiation, when knowing the exposure amount of their workplace, according to the wrong formula (14> and (15>) to calculate their device dose (including red bone dose to> and effective dose disk when the basis (14)
He - Grx
, x-
The workplace radiation basis,
The conversion factor between X and It;
-X and H F conversion factor
GB/T 16149
For certain exposure conditions, C and ℃ values are given in Appendix C Table C1 and Table 2. 3.4.3. The personnel who are connected to the neutron source of the ship should know the neutron dose at their work place. For the single energy beam, the organ dose equivalent (including the red bone dose equivalent) can be calculated according to formula (16) and formula (1?) to know the effective dose equivalent H: Hi = Crn
H = Cun
Where: CN
The organ dose produced by the unit neutron dose is the effective dose equivalent produced by the unit neutron dose.
-+ (16)
++++++++*+( 17) Under the basic exposure conditions, the C: and Crv values of the exposed are plotted in Tables D2 and D3 of the Appendix. For medium-range sources that also produce radiation, the basic radiation exposure and effective dose equivalent of the personnel caused by the radiation should also be calculated. For a medium-range source of a certain nuclide, the radiation exposure rate per gram at a distance of 1m from the source center is entered in Table [3] of the Appendix. 838
Correct element extension
GA/r 161491995
Appendix A
Exposure rate constants
(Supplement)
Exposure rate constants of some radionuclides (special units
S1 units
X10c+m
R+ru*h+i?
kge: Bg?
Element name
Relaxation
Guanghehezhe
Special unit
+thg++ - Kn?
~c,45?
.c.cn7
--0. 4 26
R - m*/(h-ci)
~ 0. 0 yuan
Gn/T 16149—1995
Conversion coefficients between personal dosimeter monitoring exposure and organ dose, effective dose equivalent (supplement)
Table B Conversion coefficients between personal dosimeter monitoring exposure and organ dose under different exposure conditions ×10-S/R
Radioactive radiation
Male
Upper part of the body
Incident! Directivity
1.00 0. R9
: 0. 67 1. 24
IkeVx-ray
Human radiation! Isotropic
a0keX-ray
SckeVx-ray
0.C, c. 63
G.1500.53
0. 21 : 3. 12
Table 132 Conversion coefficients between personal dose monitoring exposure and effective dose equivalent under two irradiation conditions of X-ray × 1℃ \S/k
Scientific work
Forward human radiation
Isotropic
14gkeVx-ray
BukeVX-ray
3ckeVx-ray
GB/T16149-1995
Appendix C
Conversion coefficients between free air exposure and red bone marrow effective dose equivalent (supplement)
Conversion coefficients between free air exposure and red bone marrow dose for wide-point parallel light or multiple-portal irradiation
Forward human radiation
Salt conversion coefficient L×1℃ \Cy/R]
Backward radiation
0. 4 yuan-1
Isotropic radiation
0. 501 items
Table C2 Conversion coefficients of air exposure and effective dose for broad beam parallel photons or isotropic radiation
10-:
Front incident
Backward incident
Conversion coefficients [×10\Sv/R_
Need to be input
1n- 28
Rotating irradiation
0320 0
.0.3587
0, 846
Isotropic photon
Feng·} source
Ra-Ein
aTu-Rie
oPu Le
Neutron mass
. 00 10 *
.co :o.
. :n 20-*
1.G0 10 4
5. Cu 1n-1
Table 132
GB/T16149—1995
Characteristics of nuclear neutron sources and dose per unit neutron fluence (supplement)
Niu Gao period
1621: year
2436
Characteristics of some nuclear neutron sources
Medium-average energy
Number of neutrons produced per becquerel
×10=a
Number of neutrons produced per unit neutron fluence under non-irradiation conditions
Number of neutrons produced per unit neutron fluence
×10=a
Number of neutrons produced per unit neutron fluence under non-irradiation conditions
Forward incidence
Backward incidence
2. 2. : 10n
2. 54×0 #
Rotating irradiation
Correction: The conversion coefficients in the table were determined before 1985. According to the new standard for neutrons in 1985 (IC:RP, 1985), the values in the table should be multiplied by 2.R4a
Neutron radiation
GB/T 16149:- 1995
Effective dose conversion coefficient per unit neutron injection in general radiation cases [×1G\Sv·cm]
Forward radiation
Ancient radiation
Internal radiation
Comparative irradiation
(565>
Let: The conversion coefficients in the table were determined before 1985. According to the new standard for neutrons in 1985 (TC:RP, 185>), the values in the table should be multiplied by 2. The particles in brackets are extrapolated from the original data. 4
CB/T 16149-1995
Appendix E
Investigation of personnel's radiation exposure history
(Supplement)
In order to verify the personnel's dose, the relevant units and departments should provide the personnel's personal and workplace dose monitoring data as much as possible. In addition, the relevant professionals should be responsible for detailed investigation, verification and recording of personnel's radiation exposure history (including whether they have been exposed to external radiation). Personnel who are exposed to external radiation sources should fill in the contents included in Table E1, and medical diagnostic line workers should fill in the contents included in Table E2. The filled contents should be investigated and verified, and approved by the personnel's unit before they can be used as the basis for estimating personnel doses. Table E1 Personnel's exposure history survey form for radionuclide radioactive sources Name
Release date and time of diagnosis and treatment in the hospital
Room in the unit
Working years position
Pathogen number
Radiation work wearing
Investigation unit
Opening and researching radioactive barrier time companybZxz.net
Filling person
Teaching radiation working years
Political radiation source change radiation source from the source of music
For consultation protection
Mother operation operation
Distance, cm name enough, material epidemic time, min number of times
Dare to radiate staff single shock certificate (seal ) Note: If the type of radiation source, activity, distance, and time of use are changed, a new line should be filled in. The new note is: the distance from the radiation source refers to the height of the personnel's torso at the center of the radiation source during operation: the selected time refers to the exposure time for each operation: the distance analysis time can be compared with the actual operation or simulation report. The data block will be rewritten, and there will be no worry about the transmission of the environment: @ If you have been exposed to accidental exposure, you should also fill in the form. The date of filling in the approval item and the date of filling in the item in the table for the type of radiation received by the operation should be alternated. 611
GHT16149—1995
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GB/T 161491995
Appendix F
Estimation of radiation level of medical diagnostic X-ray workers under various working conditions (test conditions)
For medical diagnostic X-ray workers, if there is no radiation monitoring data, an approximate radiation dose estimation can be made based on the average radiation level of medical diagnostic X-ray workers under various working conditions in my country as determined by the national collaborative survey. The specific method is as follows. Estimation of F1 radiation workload
If a person performs radiation work under the following conditions during a certain period of time, such as fat, gastrointestinal, and radiographic examinations, the radiation dose of each person can be calculated based on the radiation dose of each person in the three types of examinations (number of people>W..W. W) and converted into equivalent radiation workload W, that is, W=W.-(17.3W+0.605Wj)×35/t
The actual average noise light time of a person's chest X-ray examination is 5: Wu Zhong:
The average noise light time of a person's chest X-ray examination is 1. When = 35, then
W. -W.+ 17. 3W,-0. 695Wf
（F1)
++++++(2)
It should be noted that, for radiography, only under the operating conditions of septum or α room protection can the dose be calculated according to I(F1) or I(F2). When the radiography operation is performed under the conditions of partition or lead room protection, the radiography T. as the basis should be multiplied by 0.695×35/1 to calculate the equivalent chest dose under the operating conditions of partition rate protection. For special examinations (such as whole-body radiography, pyelography, etc.) performed by doctors without staying at the diagnosis bedside during class time, the average number of films per person for this type of examination should be used to estimate the retrograde dose under the corresponding protective conditions. F2 Estimation of exposure dose
Based on the survey data on radiation levels in medical diagnostic work places in my country, and taking into account the use of lead by personnel, Table F1 gives the average exposure rate under various working conditions. Table F1 Classification and average exposure rate (tnR/h) of various operating conditions of medical diagnostic X-ray machines: Protection conditions
With drill chair, with lead floor
With aluminum chair
Without aluminum clamps
Without new loads
Without new loads
Without backrest
Without skirt
Large capacity safety
X-ray machine cell penetration
(TOmA)
X-ray machine chest
Limit sequence
X-ray machine abdominal selection
Anti-expansion "
X-ray anti-chest penetration
-1(45. 5)
Note: 1. The values in the table are the average exposure rates under each working environment. The numbers before the numbers are the sum of the above data. 2. For hand-held X-ray machines with a rated output below 15A minus 1:mA, which have been upgraded for 40 years or are located at a working place with an area of less than 10m from the front of the X-ray machine. 3. The half-average exposure rate given in the table is obtained by weighting the exposure efficiency of the head, chest, and hands according to the surface of the human body, and taking into account the actual protection of the parts of the body. For example, if the average exposure time of a person engaged in a chest X-ray examination is, then the exposure rate received by him in half an equivalent chest X-ray working environment under the same working conditions is x.
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