THE IPEMB CODE OF PRACTICE FOR ELECTRON DOSIMETRY FOR RADIOTHERAPY BEAMS OF INITIAL ENERGY FROM 2 TO 50 MEV BASED ON AN AIR KERMA CALIBRATION

This report contains the recommendations of the Electron Dosimetry Wor king Party of the UK Institution of Physics and Engineering in Medicin e and Biology (IPEMB). The recommendations consist of a code of practi ce for electron dosimetry for radiotherapy beams of initial energy fro m 2 to 50 MeV. The code is based on the 2 MV (or Co-60) air kerma cali bration of the NE 2561/2611 chamber, which is used as the transfer ins trument between national standards laboratory and hospitals in the UK. The code utilizes an N-D,N-air approach. Designated chambers are the NE 2571 (graphite-walled Farmer chamber), to be calibrated against the transfer instrument in a megavoltage photon beam, and three parallel- plate chambers, to be calibrated against the NE 2571 in a higher-energ y electron beam. The practical code is supplemented by comprehensive d iscussion of the theoretical background and the sources and values of included data.