ISO INTERNATIONAL STANDARD 4037-2 Second edition 2019-01 Radiological protection 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 from 8 keV to 1,3 MeV and 4 MeV to 9 MeV Radioprotection-Rayonnements Xetgammade reference pour I'étalonnage des dosimetres et des debitmetres, et pour la détermination de leur réponse en fonction de I'énergie des photons- Partie 2: Dosimetrie pour la radioprotection dans les gammes d'énergie de8keVa 1,3 MeVet de 4 MeVa9 MeV Reference number IS0 4037-2:2019(E) @ IS0 2019 IS0 4037-2:2019(E) COPYRIGHTPROTECTEDDOCUMENT IS02019 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting below or ISo's member body in the country of the requester. ISO copyright office CP 401: Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +4122 749 0111 Fax: +41 22 749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2019 - All rights reserved IS0 4037-2:2019(E) Contents Page Foreword Introduction ..vi 1 Scope. .1 2 Normative references ..2 3 Terms and definitions .2 4 Standard instrument .3 4.1 General .3 4.2 Calibration ofthestandard instrument. .3 4.3 Energy dependence of the response of the standard instrument 3 5 Conversion from the measured quantity air kerma, Ka, to the required phantom related measuring quantity .4 5.1 General. 4 5.2 Determinationofconversioncoefficients. 6 5.2.1 General. 6 5.2.2 Calculation of conversion coefficients from spectral fluence 6 5.3 Validation of referencefields and of listed conversion coefficients usingdosimetry .7 6 Direct calibration of the reference field in terms ofthe required phantom related measuring quantity 8 7 Measurement procedures applicableto ionization chambers 8 7.1 Geometrical conditions. .8 7.2 Chamber support and stem scatter 8 7.3 Location and orientation of the standard chamber 8 7.4 Measurement corrections .8 7.4.1 .8 General. 7.4.2 Corrections for air temperature, pressure and humidity variation from reference calibration conditions .9 7.4.3 Corrections for radiation-induced leakage, including ambient radiation 9 7.4.4 Incomplete ion collection .10 7.4.5 Beam non-uniformity 10 8 Additional procedures and precautions specific togamma radiation dosimetry .10 using radionuclide sources. 8.1 Use of certified source output. .10 8.2 Use of electron equilibrium caps. .10 8.3 Radioactive sourcedecay .10 8.4 Radionuclide impurities .10 8.5 Interpolationbetween calibrationpositions .10 9 Additional procedures and precautions specific to X-radiation dosimetry .11 9.1 Variation of X-radiation output. 11 9.2 Monitor. 11 9.3 Adjustment of air kerma rate .11 10 Dosimetry of reference radiation at photon energies between 4 MeV and 9 MeV .12 10.1 Dosimetric quantities 12 10.2 Measurement ofthe dosimetric quantities .12 .12 10.2.1 General. 10.2.2 Airkerma (rate) 13 10.2.3 Phantom related operational quantities H*(10), Hp(10), H'(3) and Hp(3) .13 10.3 Measurementgeometry 13 10.4 .13 Monitor 10.5 Determination of air kerma (rate) free-in-air .14 .14 10.5.1 General @ IS0 2019 - All rights reserved iii