| Zugriffsnummer | 11532 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Dose determination in radiotherapy for medium- and low-energy x-rays in the framework of the German DIN standards |
| Autor(in); Institution |
Schneider, Ulf; 6.22, Dosimetrie der Gammastrahlung, PTB-Braunschweig
|
| Quelle/Jahr | Kilovoltage x-ray beam dosimetry for radiotherapy and radiobiology:(1999), 103 - 111 |
| Schriftenreihe | American Association of Physicists in Medicine symposium proceedings: 11 |
| Herausgeber(in) |
Ma, Chang-Ming Charlie
|
| ISBN | 1-888340-16-9 |
| Verlag | Madison, Wis.: Medical Physics Publishing |
| Konferenzangaben | Workshop on Kilovoltage X-Ray Beam Dosimetry, Stanford, Calif., April, 1997, USA |
| Freie Schlagworte | DIN 6809-4 ; DIN 6809-5 ; absorbed dose to water ; low-energy X-rays ; medium-energy X-rays |
| Zusammenfassung | The scope of the German DIN standards - one for low-energy X-rays from 10 kV to 100 kV generating potential and one for medium energy X-rays from 100 kV to 400 kV generating potential - are recommendations to the users for the determination of the absorbed dose to water in a water phantom, for the measuring of depth dose curves, for the investigation of radiation qualities, and for the selection of suitable phantom materials. In Germany, all therapy level dosemeters have to be calibrated in terms of absorbed dose to water. This requires, in general, that in a calibration laboratory the response of a field instrument has to be compared with that of a reference chamber (or secondary standard) in the reference depth within a water phantom. This is the common procedure for medium-energy X-rays, where cylindrical or thimble ionization chambers are recommended both as field instruments and as reference chambers or secondary standards. For low-energy X-rays, where flat parallel-plate chambers with a thin entrance window have to be used, there was introduced another procedure: The flat parallel-plate chamber (usually with a PMMA backing) has to be embedded in the surface of a PMMA phantom, and the whole facility has to be calibrated in such a way that the reading of the instrument indicates the absorbed dose to water at the surface of a water phantom at the same position in the radiation field. |
