Affiliation:
1. Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig, Germany
2. Gemeinschaftspraxis für Strahlentherapie und Radioonkologie (GSR), Rundestr. 10, 30161 Hannover, Germany
Abstract
Abstract
A secondary standard for ambient dose equivalent, H*(10), is necessary for the dissemination of the unit Sievert (Sv), but there is no such standard commercially available currently. Furthermore, the measurement of H*(10) instead of calculating H*(10) from air kerma and conversion coefficients is needed for unknown radiation fields. We developed a prototype of a new secondary standard for H*(10) based on a spherical 1 l ionization chamber for air kerma. This chamber was modified with copper wires at the inner surface to adjust the response of the chamber according to H*(10). Additionally, a Makrolon shell and an aluminium coating were added to optimize the response at energies below 50 keV. The prototype fulfils the requirements given in ISO 4037-2 in the energy range from 12 keV to 7 MeV. In combination with an electrometer, it can be used as area dosemeter, suitable for pulsed fields and for low energy radiation.
Publisher
Oxford University Press (OUP)
Subject
Public Health, Environmental and Occupational Health,Radiology Nuclear Medicine and imaging,General Medicine,Radiation,Radiological and Ultrasound Technology
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