Title: The PTB free-air ionization chambers
Authors: Büermann, Ludwig, Physikalisch-Technische Bundesanstalt (PTB), Fachbereich 6.2, Dosimetrie für Strahlentherapie u. Röntgendiagnostik
Contributors: HostingInstitution: Physikalisch-Technische Bundesanstalt (PTB), ISNI: 0000 0001 2186 1887
Resource Type: Text / Report
Publisher: Physikalisch-Technische Bundesanstalt (PTB)
Rights: Download for personal/private use only, if your national copyright law allows this kind of use.
Dates: Available: 2022-03-29
Created: 2021-11-15
File: Download File (application/pdf) 3.09 MB (3235302 Bytes)
MD5 Checksum: 77c561830c0c9327b00acaa08026ed88
SHA256 Checksum: ab153908bf4917485304163b11debb68b521b82a01d0f31a6a29f536ea8680f2
Keywords Dosimetry concepts and apparatus ; X-ray detectors ; Models and simulations ; X-ray generators and sources ; Radiation monitoring
Abstract: The fundamental quantity in the dosimetry of ionizing radiation is the absorbed dose to matter in units of J/kg with the special name of gray (Gy). The Physikalisch-Technische Bundesanstalt (PTB), the national metrology institute of Germany, is responsible for the realization and dissemination of the gray for x- and gamma radiation. The quantity air kerma is the metrological basis for dosimetry in radiation protection applications as well as in medical x-ray diagnostics and therapy. Air kerma for x-radiation is primarily measured using what are known as free-air ionization chambers (FACs). This technical report describes the definition of air kerma, the physical principles behind FACs, the technical design of three different FACs maintained at PTB, and the procedures and data needed to obtain the air kerma from the charge measured by FACs. This report is of general interest not only for researchers at other national metrology institutes who work with FACs but also for anyone who has air kerma calibration done for their secondary air kerma standards with traceability to FACs.
Citation: Büermann, Ludwig, 2021. The PTB free-air ionization chambers.PTB Open Access Repository. Verfügbar unter: https://doi.org/10.7795/120.20220324