Comparisons of 10-40 MeV electron and X-radiation dosimetry methods

Comparisons have been made between the dosimetry methods for 10-40 MeV electron- and X-radiation used at the radiation treatment centres in Essen and Villejuif by the respective resident staff and that used by a visiting group from the centre in Umea. The absorbed doses from both electron- and X-radiation and the relative electron depth doses were measured using thimble ionization chambers. Electron isodose curves were derived from data obtained with photographic films. In both comparisons, Essen-Umea and Villejuif-Umea, the absorbed dose and relative electron depth dose data showed good agreement while the electron isodose curves showed significant discrepancies.