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1、AReference number ISO 4037-2:1997(E) INTERNATIONAL STANDARD ISO 4037-2 First edition 1997-12-15 X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy Part 2: Dosimetry for radiation protection over the energy
2、ranges 8 keV to 1,3 MeV and 4 MeV to 9 MeV Rayonnements X et gamma de rfrence pour ltalonnage des dosimtres et des dbitmtres et pour la dtermination de leur rponse en fonction de lnergie des photons Partie 2: Dosimtrie pour la radioprotection dans les gammes dnergie de 8 keV 1,3 MeV et de 4 MeV 9 Me
3、V Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 4037-2:1997(E) ISO 1997 All rights reserv
4、ed. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Organization for Standardization Case postale 56 CH-1
5、211 Genve 20 Switzerland Internetcentraliso.ch X.400c=ch; a=400net; p=iso; o=isocs; s=central Printed in Switzerland ii Contents 1 Scope1 2 Normative references1 3 Definitions 2 4 Apparatus.4 5 General procedures.4 6 Procedures applicable to ionization chambers6 7 Additional procedures and precautio
6、ns specific to gamma radiation dosimetry using radionuclide sources8 8 Additional procedures and precautions specific to X-radiation dosimetry.9 9 Special procedures and precautions specific to fluorescence X-radiation Limitation of extraneous radiation in beams11 10 Dosimetry of reference radiation
7、 at photon energies between 4 MeV and 9 MeV 11 11 Uncertainty of measurement 22 Annex A (informative) Determination by ionization chamber measurements of air kerma under receptor- absent conditions and of absorbed dose to tissue (water) under receptor conditions24 Annex B (informative) Bibliography
8、27 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO ISO 4037-2:1997(E) iii Foreword ISO (the
9、 International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committe
10、e has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechni
11、cal standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 4037-2 was prepared by Te
12、chnical Committee ISO/TC 85, Nuclear energy, Subcommittee SC 2, Radiation protection. This first edition of ISO 4037-2, along with ISO 4037-1, cancels and replaces the first edition of ISO 4037:1979, which has been technically revised. ISO 4037 consists of the following parts, under the general titl
13、e X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy. Part 1: Radiation characteristics and production methods Part 2: Dosimetry of X and gamma reference radiation for radiation protection over the energy r
14、anges 8 keV to 1,3 MeV and 4 MeV to 9 MeV Part 3: Calibration of area and personal dosemeters Annexes A and B of this part of ISO 4037 are for information only. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545
15、001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 4037-2:1997(E) ISO iv Introduction The term “dosimetry“ is used in this part of ISO 4037 to describe the method by which the value of a physical quantity characterizing the interacti
16、on of radiation with matter may be measured at a given point by the use of a calibrated standard instrument. Dosimetry is the basis for the calibration of radiation protection instruments and devices and the determination of their response as a function of the energy of the radiation of interest. At
17、 present, the quantities in which photon secondary-standard instruments or sources are calibrated for use in radiological protection calibration laboratories relate to measurements made in free air, i.e. air kerma. NOTE Throughout this part of ISO 4037, kerma is used as an abbreviation for air kerma
18、. In order to correlate measured physical quantities with the magnitude of a biological effect, a quantity of the dose equivalent type 1 is required for use in radiation protection. ICRU has defined such quantities 2 and a further International Standard will be issued containing tables of conversion
19、 coefficients from air kerma to these dose equivalent quantities (see ISO 4037-3). Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permi
20、tted without license from IHS -,-,- INTERNATIONAL STANDARD ISOISO 4037-2:1997(E) 1 X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy Part 2: Dosimetry for radiation protection over the energy ranges 8 keV
21、to 1,3 MeV and 4 MeV to 9 MeV 1 Scope This part of ISO 4037 specifies the procedures for the dosimetry of X and gamma reference radiation for the calibration of radiation protection instruments over the energy range from approximately 8 keV to 1,3 MeV and from 4 MeV to 9 MeV. The methods of producti
22、on and nominal kerma rates obtained from these reference radiations are given in ISO 4037-1. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO 4037. At the time of the publication, the editions indicated
23、 were valid. All standards are subject to revision, and parties to agreements based on the part of ISO 4037 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International
24、Standards. ISO 4037-1:1), X and gamma reference radiation for calibrating dosemeters and doserate meters and for determining their response as a function of photon energy - Part 1: Radiation characteristics and production methods. ISO 4037-3:2), X and gamma reference radiation for calibrating doseme
25、ters and doserate meters and for determining their response as a function of photon energy Part 3: Calibration of area and personal dosemeters. ICRU Report 33:1980,Radiation quantities and units. VIM, 1984,International Vocabulary of Basic and General Terms in Metrology, BIPM-IEC-ISO- OIML. 1) To be
26、 published. (Revision of ISO 4037:1979) 2) To be published. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permitted without license fr
27、om IHS -,-,- ISO 4037-2:1997(E) ISO 2 3 Definitions For the purposes of this part of ISO 4037, the definitions given in ICRU Report 33, in the International Vocabulary of Basic and General Terms in Metrology (VIM) and the following definitions apply. 3.1 reference conditions conditions of use for a
28、measuring instrument prescribed for performance testing or conditions to ensure valid comparison of results of measurements VIM NOTE The reference conditions generally specify reference values or reference ranges for the parameters affecting the measuring instrument. For the purposes of this part of
29、 ISO 4037, the reference values for temperature, atmospheric pressure and relative humidity are as follows : ambient temperature : 293,15 K; atmospheric pressure : 101,3 kPa; relative humidity : 65 %. 3.2 standard test conditions value (or range of values) of the influence quantities VIM or instrume
30、nt parameters that are specified for the dosimetry of the radiation fields. NOTE The range of values for ambient temperature, atmospheric pressure and relative humidity are as follows : ambient temperature : 291,15 K to 295,15 K; ambient pressure : 86 kPa to 106 kPa; relative humidity : 30 % to 75 %
31、. Working outside this range may result in reduced accuracy. 3.3 ionization chamber ionization detector consisting of a chamber filled with a suitable gas, in which an electric field, insufficient to induce gas multiplication, is provided for the collection at the electrodes of charges associated wi
32、th the ions and the electrons produced in the sensitive volume of the detector by the ionizing radiation 3 NOTE The ionization chamber includes the sensitive volume, the collecting and polarizing electrodes, the guard electrode, if any, the chamber wall, the parts of the insulator adjacent to the se
33、nsitive volume and any necessary caps to ensure electron equilibrium. 3.4 ionization chamber assembly ionization chamber and all other parts to which the chamber is permanently attached, except the measuring assembly NOTE For a cable-connected chamber, it includes the stem, the electrical fitting an
34、d any permanently attached cable or pre- amplifier. For a thin-window chamber, it includes any block of material in which the ionization chamber is permanently embedded. 3.5 measuring assembly device for measuring the current or charge from the ionization chamber and converting it into a form suitab
35、le for display, control or storage 3.6 reference point of the ionization chamber point to which the measurement of the distance from the radiation source to the chamber at a given orientation refers NOTE The reference point should be marked on the assembly by the manufacturer of the instrument. If t
36、his proves impossible, the reference point should be indicated in the accompanying documentation supplied with the instrument. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/12/2007 21:
37、31:29 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO ISO 4037-2:1997(E) 3 3.7 point of test location of the reference point of the ionization chamber for calibration purposes and at which the conventionally true kerma rate (see 3.11) is known 3.8 chamber orientation ef
38、fect change in the ionization current from the ionization chamber as the directional incidence of the reference radiation is varied 3.9 calibration factor ratio of the conventional true value of the quantity the instrument is intended to measure divided by the indication of the instrument, corrected
39、 to stated reference conditions 3.10 calibration factor factor which converts the ionization current or charge, corrected to reference conditions, to the conventional true value of the dosimetric quantity at the reference point of the chamber 3.11 true value value which characterizes a quantity perf
40、ectly defined, in the conditions which exist when that quantity is considered NOTE The true value of a quantity is an ideal concept and, in general, cannot be known exactly. Indeed, quantum effects may preclude the existence of a unique true value VIM. 3.12 conventional true value of a quantity best
41、 estimate of the value of the quantity to be measured, determined by a primary or secondary standard or by a reference instrument that has been calibrated against a primary or secondary standard EXAMPLE: Within an organization, the result of a measurement obtained with a secondary standard instrumen
42、t may be taken as the conventional true value of the quantity to be measured. NOTE A conventional true value is, in general, regarded as being sufficiently close to the true value for the difference to be insignificant for the given purpose. 3.13 response ratio between the indication of the measurin
43、g assembly and the conventional true value of the measured quantity at the position of the reference point in space NOTE The response usally varies with the spectral and directional distribution of the incident radiation. 3.14 response time time interval between the instant when a stimulus is subjec
44、ted to a specified abrupt change and the instant when the response reaches and remains within specified limits of its final steady value VIM 3.15 deviation from linearity Percentage deviation from linearity given by : = 100 (mQ/Mq -1) where M and Q refer to the indication and input at a chosen test
45、point, respectively ; m is the indication observed for some other input signal q. NOTE For multirange instruments, the above definition is applicable to each range. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/997
46、2545001 Not for Resale, 04/12/2007 21:31:29 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO 4037-2:1997(E) ISO 4 3.16 leakage current total detector current flowing at the operating bias in the absence of radiation 3 3.17 zero drift slow variation with time of the indic
47、ation of the measuring assembly when the input is short-circuited 3.18 zero shift sudden change in the scale reading of either polarity of a measuring assembly when the setting control is changed from the “zero“ mode to the “measure“ mode, with the input connected to an ionization chamber in the abs
48、ence of ionizing radiation other than ambient radiation 3.19 primary standard standard of a particular quantity which has the highest metrological qualities in a given field 3.20 secondary standard standard, the value of which is fixed by direct or indirect comparison with a primary standard 4 Apparatus 4.1 General The instrument to be used for the measurement of the reference radiation shall be a secondary standard or other appropriate instrument. Generally this comprises an ionization cham